Structural Construction Works Level - Ii: Based On March 2022 Version-I Curriculum

STRUCTURAL CONSTRUCTION
WORKS
LEVEL – II
Based on March 2022 Version- I Curriculum
Module Title: - Repair and Rectify Structural

Construction work
Module code: EIS SCW2 M08 0322
Nominal duration: 60 Hours
Prepared by: Ministry of Labor and Skill
August, 2022
Addis Ababa, Ethiopia
Table of Content
Acknowledgment
Ministry of Labor and Skills and Regional TVT Bureau wish to extend thanks and
appreciation to the many representatives of TVT instructors and respective Ministry of Labor
Page 2 of 80 Ministry of Labor and Skills Repair and Rectify Structural Version -1
Author/Copyright construction work August, 2022
and Skills experts who donated their time and experience to the development of this
Teaching, Training and
Acronym
TTLM Learning Materials
AIA Annual Investment Allowances
TTLM Teaching, Training and Learning Materials
TVT Technical and vocational Training
PVC Polymerizing Vinyl Chloride
ACP Aluminum composite panels
Introduction to the Module
In structural construction work; Repairing and Rectifying Structural construction work

module helps the trainee how to plan and prepare for repair works, Carry out minor repairs,
rectification of cracks and other major defects. And it is also designed to meet the industry
requirement under the structural construction work occupational standard, the knowledge,
attitudes and skills required in Erect Pre-Cast Concrete Structural & Cladding Units
This module covers the units:
 Plan and prepare.
 Carry out minor repairs
 Carry out rectification of cracks and other major defects
 Clean up
Learning Objective of the Module
 Plan and prepare.
 Carry out minor repairs
 Carry out rectification of cracks and other major defects
 Clean up
Module Instruction
For effective use this modules trainees are expected to follow the following module
instruction:
1. Read the information written in each unit
2. Accomplish the Self-checks at the end of each unit
3. Perform Operation Sheets which were provided at the end of units
4. Do the “LAP test” giver at the end of each unit and
5. Read the identified reference book for Examples and exercise
Unit one: Plan and prepare
This unit is developed to provide you the necessary information regarding the following content
coverage and topics:
● Work instruction
● Safety plans and policies
● Signage/barricade requirements
● Tools and Equipment
● Calculate Material quantity
● Materials handling
● Environmental protection
This unit will also assist you to attain the learning outcomes stated below. Upon completion of
this learning guide, you will be able to:
● Apply Work instruction
● Follow Safety plans and policies
● Implementing signage/barricade
● select tools and equipment
● Calculate Material quantity
● Identify materials handling
● Identifying environmental protection
1.1 Work Instruction
Work Instructions are documents that clearly and precisely describe the correct way to
perform certain tasks that may cause inconvenience or damage if not done in the established
manner. That is, describe, dictate or stipulate the steps that must be followed to correctly
perform any specific activity or work. A document describing specific activities and tasks
within the organization. It contains the greatest amount of detail.
As a component of a process, “defines how one or more activities in a procedure should be
executed in detail, using technology or other resources.
Here are some examples of documented work instructions which may be found on a typical
construction site:
 Working Drawings issued for construction such as Plans, elevations, sections
etc.
 Specifications/Contract specifications
 Construction method statements
 Quality requirements
 Operational details
 Maintenance manuals
1.2 Safety plans and policies

1.2.1. Occupational Safety and Health
The word safety refers to your freedom from danger, injury and damage, and to your personal
security.
1.2.2. What Safety Means
 Safety means a complete understanding of your work and knowledge of every

step that must be taken and the realization that mistakes could be costly to
yourself and to the company.
 Safety means good judgment. Never rely on luck; always be prepared to cope
with unexpected situations and being alert when following your routine.
 Safety means remembering the safety rules set up by your company and
applying them every minute when you are on the job.
1.2.3. Goals
The goal of safety basically focus on the following points
Maintaining a safe and healthy working environment.
Preventing fatalities and lost time injuries.
Preventing damage to the equipment, facilities and potential effects on

progress.
Eliminating risk to the environment.
No fires. A Safe and Productive Project, in Scheduled time.
1.2.4. Safe Work Method
A written Safe Work Method for a job is prepared by the Safety Personnel in
consultation with the concerned engineers. The Work Method helps to foresee the risk
involved in the job, take precautionary action for the risk involved and plan the
materials required for the safety cause. The safe work method is methodically done as
followed:
a. Approach Safety.
b. Work Method Safety.
c. Work area Safety.
d. Men Material and Machinery.
Factors that Contribute to the Occurrence of Accidents in the Construction Industry:
1. Fall from heights is the predominant causes of accidents
2. Lack of supervision for workers working at heights
3. Workers lack awareness on OSH
4. Workers have limited trainings
5. Due to lack of training, workers
 Build improper temporary structures

 Tolerate improperly guarded floors
 Work with unstable/unsecured/scaffolds
6. Accident reports lack relevant information
7. Proper investigations are hardly conducted
1.3 Signage/Barricade Requirements

This safety signs, tags, and barricades used on sites administered by Reclamation. This also
covers standard hoisting signals and provisions about the use of signal persons.
1.3.1. Sign requirements

It shall be ensured that safety signs are erected to warn workers of specific hazards and to
communicate necessary precautionary measures and emergency actions.
As a minimum, it shall be ensured that safety signs are erected in accordance with
Queensland Work Health and Safety Regulation 2011, including, but not limited to:
 confined spaces;
 Specific personal protective equipment (PPE) requirements;
 Hazardous chemicals;
 Asbestos;
 lead;
 Fire protection equipment;
 Hazardous areas;
 Emergency and first aid information;
 Emergency eye wash and shower; and
 Traffic management and pedestrian control.
Barricading requirements barricading controls shall be implemented and authorized as part of
the safe work system to protect persons from hazards such as:
Being struck by falling objects;
Being struck by moving plant;
Fall from height, including falling into open excavations, penetrations,
and falls from unprotected edges such as removed flooring, walkways,
stairs and / or hand railings.
Exposure to hazardous chemicals
1.3.2. Types of barricading

Barricades can be classed as either a soft barricade or a hard (solid) barricade. Soft barricades
are those that use an approved tape to prevent or restrict access to an area. A hard barricade is
a physical structure such as scaffold tubes or water filled devices that prevent or restrict
access to an area.
A. Soft barricades:- they are to be used to identify and protect personnel from general
hazards and also those which are high risk and may pose a risk to life and health.
Fig1.1.Soft barricades
B, Solid barricades:- the purpose of a solid barricade is to provide a physical barrier capable
of performing the same function as a permanent guardrail.
A solid barricade shall:
 Have a solid top and mid rail (E.g. scaffold tube or equivalent) with the applicable
sign attached.
 The installation of a kick rail or mesh to contain objects etc. shall be by risk
assessment and detailed in the unprotected edge risk control authorization.
 Where solid barricades are used they shall be accompanied with signs to communicate
the hazard information. As appropriate, barricade tape may be used to highlight the
existence of the barricaded area.
Solid barricades example
Fig.1.2. Solid barricades:-
Construction Safety Signage
Warning / Safety Signs

A visual alerting device in the form of a label, placard or other marking which advises
the observer of the nature and degree of potential hazards which can cause injury or death.
Persons should aware to the following:
A. Specific Hazards
B. Degree or Level of Seriousness
C. Probable consequence of involvement with the hazards
D. How hazards cab be avoided
Location
Safety signs shall be placed such that they will:
 Be ready visible to the intended
viewer
 Alert the viewer to the potential
Protection
Against foreseeable damage, fading or visual obstruction caused by abrasion, ultra - violet
light, or substance such as lubricants, chemical and dirt.
Warning Signs Dimension
Where:
S = Area of Safety Sign
L = Distance of Observation
Panel Signs
Area of safety sign having distinctive background color different from adjacent areas of the
sign, which is clearly delineated by a line, border or margin.
Signal Word Panel
Area of safety that contains the signal word and the safety alert symbol
Message Panel
Area of the safety sign that contains the word messages which identify the hazard, indicate
how to avoid the hazard and advises of the probable consequence of not avoiding the hazard.
Symbol/Pictorial Panel
Area of the safety sign that contains the symbol/pictorial
Safety Color Code
Will supplement the proper guarding or warning of hazardous conditions.
1.3.3. Standard Color of Signs

SAFETY RED: FIRE PROTECTION
To call attention to fire protection equipment apparatus and facilities.
Fig.1.3. Fire Protection
SAFETY GREEN: DESIGNATING SAFETY

- Location of first aid equipment, safety devices, and safety bulletin boards.
Fig.1.4 .Safety Green Designating Safety
SAFETY YELLOW: CAUTION
- To designate caution and for marking physical hazards, such as striking against,
stumbling, falling, tripping and caught in between.
Fig.1.5 Safety Yellow Caution
SAFETY ORANGE: ALERT

- To designate dangerous parts of machines and energized equipment which may cut,
crush, shock or otherwise injure, and to emphasize such hazards when enclosure doors
are open or when gear, belt, or other guards around moving equipment are open or
removed, exposing unguarded hazards.
Fig.1.6. Safety Orange: Alert
SAFETY BLUE: PRECAUTION
- To designate caution, limited to warning against starting use of, or the movement of
equipment which is under repair or being worked upon.
Fig.1.6. Safety Blue: Precaution
Where Signage are Needed
 Usage of PPE prior to entry to the project site

 Potential risks of falling objects
 Potential risk of falling
 Explosive and flammables substances are used or stored
 Tripping or slipping hazards
 Danger from toxic or irritant airborne contaminants/substances may
exist
 Contact with or proximity to electrical/facility equipment
 Contact with dangerous moving parts of machineries and equipment
 Fire alarms and firefighting equipment
 Instructions on the usage of specific construction equipment
 Periodic updating of man-hours lost
1.4 Tools and Equipment

1.4.1. Tools
Common repairing and Rectify Structural construction work Tools used in
Construction are listed below
1. Blower: an air compressor that produces air at low pressur

2. Wire brush:
3. Mortar barrel/ drum
This is used by mason, plasterer, tiller, etc, and serves to prepare small amount of mortar
right at the working place. It is also used as temporary mortar storage, supplied from mixing
station, and to control water ratio of the mix when it gets dry. Always, keep it workable and
clean.
Fig1.7. Bucket
A Bucket is used to serve small amount of water or material and to take the tools after
4. Brush and Broom

Is used for wetting the building stones, cleaning fresh mortar joints of masonry wall, to clean
hand tools before and after use and to clean dust on surfaces.
Fig.1.8.Broom Fig.1.9. Hand broom or brush

1.4.2. Equipment/Machinery
1. Extension cable
To connect all electrical driven equipment properly
Fig.1.10. Extension Cable Drum
2. Wheelbarrow
Wheelbarrow is used to dispose disposal materials from working place, to transport or serve
materials and tools activities in the during construction site. It is the most efficient way in
transporting materials or items. ; In comparison to a barilla, (commonly used in the country),
a wheelbarrow is much more efficient. For this reason, it is operated by one person and can
be carried up to 100 kg at once. So that it saves operation cost; it is time effective and
therefore in general.
.
Fig.1.11. Wheelbarrow /85Lit

3. Grinder
Grinders are available as one hand and two hands. They are operating with high speed rotary
cutting discs. The protecting hood must not be removed by all means. A grinder is very useful
for cutting hard material like concrete, steel, natural stones or tiles. It is effective to cut
blocks or bricks perfectly than cutting with hands.
Fig.1.12. Angle grinder
4. Drilling machine
It is used to make or drill holes in concrete, stones and other building elements or material.
Drilling holes is depending up on the size and materials to be drilled, i.e, the drill bits are of
different size and types. Types of drill bit can be classified as bits for metal, wood and stone
or concrete).
Fig.1.13. Electrical drilling machine
1.5 Calculate Material quantity

1.5.1. Estimating, Purchasing, Delivery, and Storing of Repairing
materials
I. Grout
A. Estimating
1 To estimate the quantity of grout required for a job, calculate the volume of the cavity to
be filled in cubic feet. Divide the calculated volume by the yield in cubic feet of one unit of
grout to calculate how many units will be needed. Add 5% to 10% for waste and spillage,
more for smaller jobs, and less for larger ones.
2 The most common shapes of cavities encountered in grouting operations are
rectangular solids (for example, the space under a rectangular base plate), solid right
cylinders (such as the space under a round, flat-bottomed tank), and hollow right cylinders
(like the space between an anchor bolt and its hole).
Many other cavity shapes can be divided into some combination of the common shapes for
estimating purposes.
3. To find the volume V of a rectangular solid in cubic cm, multiply the length L in cm
times the width W in cm times the thickness T in cm.
V = LWT
4. To find the volume V of a right cylinder in cubic cm, multiply the square of the
diameter D in cm times π/4 times the height H in cm.
V = 0.785 D2H
5. To find the volume V of a hollow right cylinder in cubic feet, subtract the square of
the inside diameter d in feet from the square of the outside diameter D in cm and
multiply that difference times π/4 times the height H in feet.
V = 0.785 (D2- d2)H
6. If all dimensions in these equations are in m, the calculated volume will be in cubic m.
B. Purchasing
1 To compare the cost of grout needed for a job, determine the cost per cubic m for each
grout under consideration. To ensure that all prices are directly comparable, requests for
quotation should be made in cubic m units. All cost comparisons must be made on the basis
of delivered cost per cubic m to be meaningful. Grouts must not be compared, bid, or
purchased on a weight basis because there is not a constant relationship between weight and
volume. The customary unit of volume is the cubic m, so requesting quotations in cubic m
units allows direct price comparisons.
5. In estimating the quantity of grout that is sold in units other than one cubic m, divide
the manufacturer’s yield into the number 1 to determine the actual number of units
required for one cubic m. For example, if a manufacturer’s 55-pound unit has a yield
of .42 cubic feet, 1 cubic foot /.42 = 2.38 units (bags or pails) per cubic foot.
C. Delivery
1 Non shrink cement-based grout should be delivered palletized and shrink-wrapped,
and delivered to the job site in sound, dry packages.
2 Epoxy resin and hardener should be delivered, premeasured, in sealed containers,
palletized and shrink-wrapped to prevent shipping damage. Epoxy
grout aggregate, delivered as a separate component, should be premeasured, packaged in
sealed, dry bags, also palletized and shrink-wrapped to prevent shipping damage.
D. Storage
1 Non shrink cement-based grout should be stored in a dry area in accordance with ACI
instructions. The ideal storage temperature is 70°F. Avoid storing cementitious grout
below 40°F or above 90°F.
2 Preferably, epoxy grout components should be stored at a temperature between
70°F and 80°F, but never below 60°F nor above 90°F.
E. Storage Damage
Immediately remove from the job site any cement-based grout material which
becomes damp or otherwise defective. Epoxy grout aggregate that becomes damp or
otherwise defective should not be used and should be removed from the job site.
Liquid components that are found to be defective should also be removed from the job
site.
II. Concrete Repair Materials
A. Estimating
1 To estimate the quantity of concrete repair material required for a job, calculate the
volume of the cavity to be filled in cubic cm. Divide the calculated volume by the yield in
cubic cm of one unit of concrete repair material to calculate how many units will be needed.
Add 5% to 10% for waste and spillage, more for smaller jobs and less for larger ones.
2 The most common cavity shape encountered in repair operations is a rectangular
solid. When the shape of the area to be repaired is irregular or uneven in depth, the average
length, width, and depth must be determined by measurement or by estimate. But consider
that an irregular shape should be squared off for a durable repair.
3 To find the volume V of a rectangular solid in cubic cm (for example, a floor
overlay) multiply the length L in cm times the width W in cm times the thickness T in cm.
V=LWT
The calculated volume will be in cubic cm.
B. Purchasing
To compare the cost of a concrete repair material needed for a job, determine the cost per
cubic m for each material under consideration. Because concrete repair materials are sold in
units that may be of different sizes, and may yield different volumes of concrete for a given
weight.
C. Delivery
Concrete repair materials should be delivered, premeasured, and packaged in sealed, dry
bags, and on stretch-wrapped or shrink-wrapped pallets to prevent shipping damage.
D. Storage
1. Concrete repair materials should be stored in a dry location at a temperature neither near
70°F, but never below 40°F nor above 90°F.
2. Concrete repair materials that become damp or otherwise defective should not be used and
should be removed from the job site.
3. Concrete repair materials that are beyond the manufacturer’s expiration date should not
be used unless the manufacturer has requalified them by actual laboratory retest.
1.6 Materials Handling

Building materials have an important role to play in this modern age of technology.
Although their most important use is in construction activities, no field of engineering is
conceivable without their use. Also, the building materials industry is an important
contributor in our national economy as its output governs both the rate and the quality of
construction work.
Repair materials may be classified into three general groups:
 Cementitious,
 Polymer and
 Polymer modified.
Cementitious materials are those materials which require the addition only of potable water
– they may also be termed “hydraulic materials”. Polymer materials are modifying agents to
increase flexural strength and other performance properties. Both groups have advantages and
disadvantages.
Cement-Based: These generally are prepackaged materials requiring only the addition of
potable water. Their physical properties are very similar to those of concrete. As opposed to
the polymer types, cementitious products are considered “user-friendly” and users have had
considerable experience with them.
The cementitious materials achieve strengths to or greater than the concrete being repaired.
Thermal coefficients of expansion are nearly identical to that of concrete.
The main disadvantage of most cementitious products is that they don’t develop adequate
bond strength. Sand/cement mixtures, with or without “bonding” admixtures, and gypsum-
based products, exhibit this disadvantage and are usually classified as temporary patches.
Of all the properties of cementitious repair materials, bond strength is one of the most
important requirements.
One product on the market was developed specifically to produce excellent bond strength and
the other desirable properties of an ideal repair material. It is called Five Star Structural
Concrete®.
Polymer Based: These include epoxies, polyesters, and acrylics and are most commonly
used where chemical resistance is required. Most of the polymer-based repair materials
achieve high strength and good bond to a properly prepared and dry substrate.
There are some disadvantages to these materials:
 They are generally more difficult to work with as compared to cement-based
material.
 They exhibit varying degrees of toxicity and flammability and must be
used with caution.
 Proportioning the components and mixing are critical to proper curing.
Polymer-Modified: Dispersions of polymers in water have been in use for many years as
admixtures to Portland cement mortar and concrete. The property improvements from this
family of admixtures includes increased bond strength, reduced permeability, increased
resistance to freezing and thawing, and increased flexural strength. The specific property
improvement to the modified mortar and concrete will vary with the type of latex used.
Applications of these materials include floor leveling, concrete patching, and bridge deck
overlays.
In addition, all of the polymer based repair materials are more expensive than cement-based
materials. Regardless of the type of repair material, an adequate inventory should be kept in
stock. Any repair material chosen to be kept in stock must have an adequate shelf life. These
materials may remain in inventory for months and must retain their efficacy. A shelf life of a
minimum of 6 months is highly recommended. There are some companies, such as Five Star
Products, Inc., who are constantly doing research and development work in this field.
Individuals working in this area should keep in touch with Five Star Products, Inc. to stay
current with the latest developments.
Classification of repair materials
1. Patch Repair Materials
 Cementitious mortar / concrete
 Polymer modified cementitious mortar / concrete
 Polymer mortar / concrete
 Quick setting compounds
 High alumina cement based
 Calcium sulphate based
 Magnesium phosphates
 Sulphur concrete
2. Injection Grouts
 Cementitious grouts (with or without fibres)
 Gas forming grouts
 Sulpho-aluminate grouts
 Polymer grouts
3. Bonding Aids
 Polymer emulsion type
 Polymer resin type
4. Resurfacing Materials
Protective coatings and membranes
Impregnants and hydrophobic sealers
Toppings / screeds
Overlays
Gunite / shotcrete
5. Other Repair Materials
Corrosion inhibitors
Rebar protective coatings
Cathodic protection
Re-alkalization
Materials for surface preparation
Chemical rust removers for corroded reinforcement
Joint sealers
Surface coatings for protection of RCC
Polyester Resins
A two-part polyester resin (unsaturated polyester such as methyl methacrylate) based material
suitable for the repair, surfacing, jointing and bedding of concrete, brickwork and masonry.
Available in summer and winter grades, the mixed mortar will harden to give rapid strength
gain and can be placed in section thicknesses of 5mm to 50mm in single layers. Thicker
sections can be achieved by placing multiple layers. The bond strength developed is stronger
than the tensile strength of most construction materials. Typical uses include bedding and
fixing of precast concrete units, fixing of concrete barrier units, patch repairs to concrete
floors, bedding of coping stones and in fills where rapid service use is required.
Acrylic Concrete and Mortar

In this type, aggregates are mixed together with acrylic polymer to make concrete / mortar.
Methyl methacrylate (MMA) and high molecular weight methacrylate (HMWM) monomers
are used to make concrete. All components of the product can be mixed together and placed
over a patch area filled with preplaced aggregates. Due to its rapid strength gain and high
ultimate strength, it is widely used in bridge slabs, parking garage decks, industrial
warehouse floors and tanks.
Quick Setting Compounds
Repairs in heavy trafficked areas are possible using faster setting and curing materials such as
high alumina cement containing compounds, magnesium phosphates, molten sulfur and
calcium sulphate based materials.
Grouts
Grout is a type of mortar used to fill joints, cracks, and cavities in tiles, masonry, and
brickwork. It typically consists of water, cement, and sand; or cement and water. Used in
semi-liquid form, may be pumped, spread, or poured into cavities and allowed to harden,
creating a tight, water-resistant seal.
The three main types of grout are epoxy, Portland cement - based,and furan resin. The epoxy
type is strong and water resistant. It is available in 100 percent epoxy resin and modified
epoxy emulsion form. Epoxy grout is generally more expensive than other types and can be
difficult to find.
Grouting formulations are comprised of three basic elements: binder (clay types and
properties, lime, synthetic), aggregate (sand, synthetic materials) and dispersant (water).
Essential parameters for repair materials

 Low shrinkage properties
 Requisite setting / hardening properties
 Workability
 Good bond strength with existing sub-strate
 Compatible coefficient of thermal expansion
 Compatible mechanical properties and strength to that of the sub-strate
 Should allow relative movement, if expected, particularly in case of sealing
of cracks or dealing with expansion joints
 Minimal or no curing requirement
 Alkaline character
 Low air and water permeability
 Aesthetics to match with surroundings
 Cost
 Durable, non-degradable or non-biodegradable due to various forms of
energy, life, UV rays, heat, etc.
 Non-hazardous / non –polluting.
Criteria for selection of repair materials

A careful selection of repair material is necessary for the following reasons (Shan Somayaji,
1995 and ACI. 1980)
1 Almost every repair job has unique condition and special requirements
2 The composition and properties of repair materials have a profound effect and cured
on
the performance and durability of a repair.
3 The repair materials perform adequately only if they are prepared, applied and cured
as per the specified procedures, which may necessitate the use of appropriate tools
and considerable skill.
4 Repair materials, being generally proprietary in nature, are very costly.
Fig.1.14. Possible loads acting on a repair

1.7 Environmental protection
1.7.1. What is Environmental Management?
Environmental management (EM) is a subject that combines science, policy, and
socioeconomic applications. It primarily stresses on finding solution to practical
problems that people face in cohabitation with nature, resource exploitation, and waste
production.
In a purely anthropocentric sense, environmental management is all about dealing with the
fundamental issue of how to innovate technology to evolve continuously while limiting the
degree to which this process alters natural environment. Thus, Environmental management is
closely linked with issues regarding sustainable economic growth, ensuring fair and
equitable distribution of resources, and conserving natural resources for future generations.
There are a number of advantages to undertaking environmental management and these

include:
i. Cost savings
ii. Ensuring legislative compliance
iii. Anticipating future legislation
iv. Reduced environmental risk
v. Meeting supply chain requirements
vi. Improved relations with regulators
vii. Improved public image
viii. Increased market opportunities
ix. Employee enthusiasm
1.7.2. What is an Environmental Policy?

An environmental policy is a document prepared by a company or an organization which
clearly sets out its overall aims and intentions with respect to the environment. An
environmental policy provides a sense of direction for a company and shows that it is
committed to managing its environmental affairs in a responsible way. The policy should be
endorsed by the company’s senior management and should be publicly available. It should
be an integral part of the business strategy and be compatible with company’s other policies
(e.g. on quality and on health and safety).
Each of these benefits is now examined below:
Cost Savings
Most, if not all people, wish to protect the environment. However, many businesses fear that
protecting the environment by improving their environmental performance will cost money.
They fear there will be a conflict between their desire to protect the environment and their
desire to keep down costs and run a successful business.
The good news is that many businesses have discovered that far from increasing costs,
improving environmental performance actually reduces costs. Many companies have found
that it is possible to save money, sometimes large sums of money, by improving their
environmental performance.
Cost savings within a company or a firm can be achieved through changes in areas such as:
i. Process Efficiency
ii. Product Design
iii. Waste Disposal
iv. Sourcing of Raw Materials
v. Infrastructure
vi. Packaging and Transport
Various ways of achieving cost savings are described briefly below:
Process Efficiency
Improving the efficiency of existing processes
Optimizing the performance of existing processes minimizes the use of raw materials and
energy and the production of waste. Reduced use of raw materials and energy and reduced
waste production are all good for the environment and the reduced resource costs and waste
disposal costs are good for business. Proper maintenance of equipment is important as it
minimizes costly downtime and the resource waste often associated with shutdown and start-
up periods.
Introducing more efficient processes
Introducing new and more efficient processes also reduces resource use and waste
production. Many companies have been able to make large cost savings by reducing the
amount of raw materials, energy and water that they use.
Product Design
It may be possible to redesign a product so as to reduce the amount of resources it contains

whilst still maintaining the level of service it provides.
Waste Disposal - Making Money from Waste
As mentioned above, improving process efficiency will reduce the amount of waste that a
process produces. Once waste has been generated, it is often possible to reuse it or pass it on
to other companies that can use it and so avoid the costs of waste disposal.
Sourcing of Raw Materials
Changing the source of raw materials used in a particular process can result in cost savings.
Companies could make large savings by using recycled wool rather than virgin wool to
manufacture its products, or use recycle paper rather than manufactured paper that could save
substantial number of tress being felled.
Infrastructure
It is also possible to make savings by making efficiency changes to infrastructure e.g.
installing energy efficient lighting, insulating buildings, improving the efficiency of heating
systems.
Packaging and Transport
Once goods have been produced, they need to be packaged and transported. It is possible to
make cost savings in these areas at the same time as improving environmental performance.
Ensuring Legislative Compliance
By ensuring that it complies with relevant environmental legislation, a company or a firm

can avoid the possibility of being fined by the regulatory authorities for noncompliance and
the adverse media publicity and public criticism & outrage that can accompany such fines.
Anticipating Future Legislation
Developing an awareness of likely changes in environmental legislation allows companies to

plan for these changes and make appropriate investment decisions. If a company or an
organization is not aware of proposed legislation it may make investments that are futile
when the new legislation is enacted. Alternatively, a company may find out about a
legislative change at the last minute and be forced to undertake rapid investment to comply
with its requirements. Prior knowledge of likely changes allows a longer time period over
which to make the necessary investment and prevent possible cash flow problems.
Reduced Environmental Risk
Environmental risk is the single largest hidden risk for many companies. By undertaking
environmental risk assessment as part of the environmental management process it is
possible to reduce the risk of the occurrence of events that could have adverse environmental
consequences. Banks, insurance companies and investors all base their decisions on an
assessment of risk. The higher the risk, the less likely a bank is to lend, the less likely
investors are to invest and the higher insurance premiums are likely to be.
Therefore a reduction in environmental risk is likely to be viewed favorably by all these

parties, putting a company in a better position to obtain loans and insurance cover and to
attract investment.
Meeting Supply Chain Requirements
An increasing number of large organizations are requiring their suppliers to demonstrate
sound environmental management and are prepared to delist those that fail to do so. In some
cases having an environmental policy is not considered sufficient proof of sound
environmental management and evidence is required that a company is taking action to
meet the commitments set out in their policies. Hence, undertaking effective environmental
management will increasingly be necessary to gain or maintain supplier status with large
organizations.
Improved Relations with Regulators
The ability to demonstrate sound environmental management may lead to environmental

regulators taking a more “hands-off” approach to regulation e.g. a reduction in the number of
inspection visits required per year.
Improved Public Image and Community Relations
By publicizing its efforts to improve environmental performance, a company can improve its
public image, thereby enhancing its position in the market place. And by demonstrating
sound environmental management, a company can reassure the local community about its
activities and thus build up good community relations.
Increased Market Opportunities
Lower production costs resulting from environmental management and good public image
resulting from publicizing good environmental performance can result in a company
increasing sales and gaining a larger market share.
Employee Enthusiasm
The environment is an issue about which many people are concerned. Undertaking
environmental management can generate a lot of enthusiasm within a company as it allows
employees to express their environmental concern in a practical way by contributing towards
improving environmental performance
Self-Check 1 Multiple choice
Instruction: Select the best answer and encircle the letter
1. ---------One of the following including in Work Health and Safety Regulation 2011,
A/Specific personal protective equipment (PPE) requirements;
B/Hazardous chemicals;
C/Fire protection equipment
D/ All of the above
2. A construction worker should aware one of the following safety rule
A/Specific Hazards
B/Probable consequence of involvement with the hazards
C/How hazards cab be avoided
D/ All of the above
3. The purpose of a solid barricade is to provide a physical barrier capable of performing
the same function as a permanent guardrail.
A/ True B/ False C/ A & B are correct D/ None
4. ………is used to dispose disposal materials from working place, to transport or serve
materials and tools activities in the during construction site.
A. spade B. Wheelbarrow C. mixer D. ladder
5. Creating a good environment will play an important role in guaranteeing the quality and
safety of construction projects,
A/True B/ False C/Both D/All
6. Minimizing waste, sorting waste into the appropriate bins and leaving the site clean and
tidy at the end of each day.
A/ Land disturbance B/ Noise and vibration
C/Waste management D/All
7. -----is firstly to do rational planning and management of construction plan
A /Control of working environment B/Waste management
C/Noise and vibration D/ None
Test II: short Answer writing

Instruction: write short answer for the given question. You are provided 3 minute for each
question and each point has 5Points.
1. What is the purpose of Personal Safety?
2. What is the advantage of bucket?
Operation Sheet 1
Operation Title Preparing Work Area
Purpose:- To apply quality work and health care

Instruction: - Using the right tools to perform your task within the given time. You have
given 10Minut for the task.
Equipment and Tools
 Shovel
 Chisel
 Brooms
 Concrete Saw
 Hammer
 Drill
 Cleaning Materials
precaution:-
 Safe working area environment
 Ensure the work area hazard free
 Avoid horse play
 Availability of proper tools and equipment

PROCEDURE,
1. Wear your PPE properly.
2. Secure workshop manuals, Specifications, tools and equipment.
3. Sort different tools and materials based on their size and kind.
4. Select appropriate way of house cleaning.
5. Identify and prepare resources and technical requirements for Carry-out Concrete
Bursting
6. Observe the proper application of Occupational Health and Safety requirements.
Quality Criteria: Assured to follow the kaizen principle
LAP Test 1 Practical Demonstration
Name: __________________________ Date: ____________

Time started: ____________________ Time finished: _______________
Instruction I: Given necessary templates, tools and materials you are required to perform the
following tasks within 10 min.
Task 1: Prepare Work Area
Unit Two: Carry out minor repairs
This unit to provide you the necessary information regarding the following content coverage
and topics:
 Effects of dusting
 Repairing damage concrete either by grinding or covering
 Repair mortars self-leveling floor compounds
 Cover and colored paints
 Repair and maintain cloven timber form work
 Maintain or repairing masonry structure
This guide will also assist you to attain the learning outcomes stated below. Upon completion of
 Repair the effects of dusting
 Repair damage concrete either by grinding or covering.
 Apply repair mortars self-levelling floor compounds.
 Apply Cover colure paints.
 Repair and maintain cloven timber form work.
 Maintain or repair masonry structure
2.1 Effects of dusting
2.1.1 Repairing effects of dusting
 What is dusting?
A dusting floor surface is marked by an Accumulation of fine material requiring to be swept
up after the floor has been used. A hand rubbed over the surface of a dusting floor will be
coated with a fine powder
 What causes Dusting?
Dusting is caused by the wearing surface being weak and the matrix not properly bonding the
fine aggregate particles. The major causes are:
 Inappropriate concrete specification for the required strength and abrasion resistance.
 The addition of water in excess of that required by the mix design. This generally
increases
 Premature finishing. If finishing operations are performed while bleed water is on the
Surface, the water will be worked back into the surface layer of the concrete producing a very
High water-cement ratio and, therefore, a low strength surface layer.
Fig2.1 Dusting Surface
 Repair of dusting surfaces
Repair of dusting floors is difficult; it is best to avoid or minimize the risk by adopting the
techniques outlined above. Recommended repair methods include:
 Application of a chemical surface hardener or dust inhibitor. In the majority of cases,
dusting can be rectified by the use of a surface hardener such as sodium or flour
silicate.
 These products react with the calcium hydroxide in the concrete to produce additional
cementitious compounds.
 Grinding the surface. In more severe cases, the complete removal of the weak surface
layer with a concrete grinder may be required. .
 Applying a topping. The weak surface layer could be removed by scrabbling and
replaced by a topping. If levels need to be maintained, a number of proprietary
topping products that bond to the existing concrete can be placed at thicknesses of
about 10 mm. If levels are flexible, a 70- to 80-mm-thick unbounded topping
(overlay) on the existing floor can be used.
 In some domestic applications, installation of a floor covering such as carpet or tiles
may be a cost effective solution. The concrete surface should be checked for adequate
strength if the floor covering is to be bonded to it.
Fig2.2 concrete surface repair
2.1.2. Practices to Minimize the Risk of Dusting

To minimize the incidence of dusting:
 Specify an appropriate concrete strength for abrasion resistance; Do not add excess
water to the concrete mix.
 In general, use concrete with a moderate slump, say 80 mm. In cold weather,
delayed setting will increase bleeding and may require the use of a lower slump. In
hot weather, acceptable setting times and bleed rates can still be achieved with
higher slump levels, providing the mix is designed to perform at such slumps
without causing excessive bleeding or segregation.
 Do not overwork the concrete initially as this may seal the surface and trap bleed
water under the surface layer. Also, fine material may be brought to the surface.
 Do not perform any finishing operations with bleed water or rainwater present on
the surface.
If rain threatens, a method to protect the surface should be available. Final bull-floating or
trowel ling should be performed only after all the bleed and surface water has evaporated or
been removed.
 Do not sprinkle or trowel dry cement into the surface of plastic concrete to absorb
bleed water or rainwater. Remove bleed water by dragging a garden hose across
the surface or by using a rubber squeegee.
Compact the surface of the floor with a surface vibrator and/or use one of the finishing
techniques giving improved abrasion resistance
2.2. Repair damage concrete either by grinding or covering
2.2.1. What is Repair?
Action taken to reinstate to an acceptable level the current functionality of a structure or its
components which are defective or deteriorated, degraded or damaged in some way is called
repair
The actions will include the following:
(i) Patching up of defects such as cracks and fall of plaster.
(ii) Repairing doors, windows, replacement of glass panes.
(iii) Checking and repairing electric wiring.
(iv) Checking and repairing gas pipes, water pipes and plumbing services.
(v) Re-building non-structural walls, smoke chimneys, boundary walls, etc.
(vi) Re-plastering of walls as required.
(vii) Rearranging disturbed roofing tiles.
(viii) Relaying cracked flooring at ground level.
(ix) Redecoration, whitewashing, painting, etc.
Rehabilitation
It is the process of bringing the structure to its original level of function including
durability and strength.
It includes:
 Removal of portions of cracked masonry walls and piers and rebuilding them
in richer mortar. Use of non-shrinking mortar will be preferable.
 Addition of reinforcing mesh on both -faces of the cracked wall, holding it to
the wall through spikes or bolts and then covering it suitably. Several
alternatives have been used.
 Injecting epoxy like material, which is strong in tension, into the cracks in
walls, columns, beams, etc.
Retrofitting
Action to modify the functionality of a structure and to improve future performance in terms
of load carrying capacity is called retrofitting.
Effects of repair, rehabilitation and retrofitting
Fig.2.3. Effects of repair, rehabilitation and retrofitting

The expected economic life of the building under normal occupancy and maintenance
conditions is considered to be as below:
(i) Monumental buildings 100 years.
(ii) RCC Framed construction 75 years
(iii) Load bearing construction 55 years.
(iv) Semi permanent structures 30 years
(v) Purely temporary structures 5 years
Surface Coatings
The protective coatings of concrete surface generally improve the durability and greatly help
to protect concrete deterioration due to environment effects. The protective coatings
properties are:
1. Possess excellent bond to substrate
2. Be durable with a long useful life normally 5 years
3. Little or no color change with time
4. Little or no chalking
5. Should have maximum permeability to allow water vapors escape from concrete
Substrate
6. Should sufficient impermeability against the passage of oxygen and carbon
dioxide
from air to concrete
7. Should be available in a reasoning range of attractive colours.
8. The properties of concrete which affect the successful application and
Performance of a coating is
(i) Porosity
(ii) Moisture content
(iii) Presence of contaminants on the surface.
Most of the protective coatings used are
(i) Bituminous coatings and mastics
(ii) Polyesters and Vinylesters
(iii) Urethanes
(iv) Epoxies
(v) Neoprene
(vi) Coal Tar Epoxy
(vii) Acrylics.
2.2.2. What causes damage to concrete?
So we've done our evaluation and now we are ready to determine what caused the damage—
this is often called troubleshooting. Start by thinking about the basic characteristics of
concrete—strong in compression, weak in tension.
Therefore, a crack implies that the concrete was in tension. Recognize that the crack is
always perpendicular to the direction of the tension—always!
Think of a typical shrinkage crack running diagonally from a re-entrant corner in a concrete
slab. The concrete was shrinking back in each direction from the corner and that diagonal
crack is perpendicular to the direction of shrinkage.
Look at a diagonal crack across the corner of a slab panel where it was run over by heavy
traffic or the sub base was poorly compacted—the bending force created tension across the
top of the slab. Take a saltine cracker and bend down the corner—it breaks in a diagonal line
exactly the same as a concrete slab. I guess you could think of a concrete slab as nothing
more than a big cracker!
Here are a few typical concrete problems and their causes:

 Corrosion of reinforcing steel: Steel rebar is protected inside concrete because the
concrete is very alkaline which prevents rust. But if there are chloride ions present,
such as from deicing salts, the chloride destroys the "passivating layer" of alkalinity
around the steel, allowing it to rust. Rust has greater volume than steel and the
expansion presses against the concrete putting it in tension and causing it to crack and
pop off. Chlorides get to the concrete through cracks or by simply penetrating through
the concrete's pore structure.
 Freeze-thaw disintegration: Concrete is porous, so if water gets in and freezes it
breaks off small flakes from the surface. Deicing salts make it worse. This is typically
called scaling and it can occur during the first winter and get worse over time. When
severe, it can lead to complete destruction of the concrete. Proper air entrainment
completely prevents scaling.
Fig2.4. Concrete crack repair Fig2.5. Concrete crack
Even decorative concrete can suffer damage, and these repairs require special expertise.
Endure Stamped Concrete
 Concrete crack repair
With low-pressure crack injection, you can permanently repair a basement leak and
foundation crack without high cost and disruptive excavation.
While concrete cracks appear to be typical, it is not recommended that they remain ignored.
Most homeowner’s best identify concrete cracks in their basement, either on the foundation
wall or on the floor. They may also recognize cracks on the garage floor, patio or in-ground
pool.
These cracks typically due to drying shrinkage, thermal movement or other causes usually are
minor and result in few problems. More often than not, a foundation crack will widen over
time and result in water seepage or possibly the loss of structural integrity. Foundation and
slab cracks are not only an eyesore, but they may hinder the value of the home.
Fig2.6 Concrete crack
Fig.2.7. Concrete crack repair
2.2.3. Why Does Concrete Need Repairing?

 Corrosion of reinforcement
 Insufficient reinforcement
 Chemical damage
 Excessive loads
 Structural damage
 Fire damage
 Seismic damage
 Blast damage
2.2.4. Repairing damage concrete by covering
Hanne card can provide new coverings or recovering in every area of the paper mill from
pulp preparation to converting.
Covering and recovering takes place at our workshop (polyurethanes, composites, rubbers
and carbides) or on site (carbides).
Hanne card also provides grinding and machining (drilling and/or grooving) services.
All types of covers can be ground at the workshop. Machining and cylindrical grinding on
metallic or carbide-covered rolls can take place on site.
In addition, Hanne card can carry out inspections, repairs and cleaning and supply expertise
and optimization.
2.3. Repair mortars self-leveling floor compounds

2.3.1. Concrete Repair Mortars
Concrete repair can be due to a number of reasons, from natural structural defects caused by
buildings settling and adjusting during temperature highs and lows to damage caused by
unexpected water ingress or produced by preventable corrosion on internal supports. While
each of these jobs will call for a repair in a similar way, i.e. filling cracks or gaps with a
specialized concrete repair mortar, the repair mortar used may differ between each of the
repairs required.
Concrete repair mortars are generally split into two different groups, cementitious and epoxy,
based on their repair qualities and both of which can be used for different applications.
Concrete Repair Mortars We Use
At Concrete Renovations Ltd, we keep stock of a variety of concrete repairs mortars, this
ensures that different systems can be correctly applied to specific repair job situations,
extending the lifetime of the repair and allowing us to closely match mortars to the original
structure in order to blend repairs seamlessly.
You have different goals for every project. Master Builders Solutions repair mortars meet
multiple application requirements, while keeping your end goal in mind. Do you need a rapid
setting mortar or one with extended working time? Are you working on a large area or
restoring fine architectural details? With our portfolio of durable repair mortars, we’ve got
you covered.
2.3.2. Epoxy Concrete Repair Mortars

Epoxy Bonding Agents
Various epoxy products are available for the bonding of freshly placed concrete to cured
concrete and of concrete to steel. Most products contain resins that are 100% solids. In severe
drying conditions, the open time for bonding coats may be too short to ensure a good bond
and such situations epoxy resin bonding is preferable.
Fig.2.8. Epoxy concrete repair
A specially formulated epoxy for use with eroded or cracked concrete flooring, epoxy
concrete repair mortars are used to provide new strength to damaged concrete and, in most
cases, offer a permanent repair that is tough enough to stand up to most heavy use.
Epoxy concrete repair mortars are popular for use in repairing concrete as they are fast curing
and can be layered up to fill cracks and gaps greater than 50mm in depth, making it versatile
for most repair situations.
2.3.3. Self-Leveling Compound

Concrete mortars are a mortar with self-leveling properties. Hydraulic cement-base
compound, selected silica sands and special additives, that when mixing them with water
form a fluid and self-leveling mass, ideal to correct imperfections in floors where thicknesses
of up to 10 mm are required.
Use of Self-Leveling Compound
 To achieve leveled surfaces

 To fill thicknesses or voids with differences between 0.5 and 10 mm (0.02 - 0.39 in)
 Ceresin DM may be used on: concrete, mortar, ceramic tiles, natural stone and old
substrates with adhesive remnants firmly attached
 The product is for indoor use only. Do not use it as final finish
Self-leveling concrete
 Self-leveling concrete is polymer-modified cement that has high flow characteristics

and, in contrast to traditional concrete, does not require the addition of excessive
amounts of water for placement.
 Self-leveling concrete is typically used to create a flat and smooth surface with a
compressive strength similar to or higher than that of traditional concrete prior to
installing interior floor coverings. Self-leveling concrete has increased in popularity
as the degree of flatness and smoothness required for floor covering products has
increased, with vinyl goods becoming thinner and floor tiles becoming larger, for
example.
 Floor Self-Leveling Screed is a cement-based, rapid-hardening, low-shrinkage, self-
leveling 'underlay', used to rectify uneven or damaged concrete and other cement-
based floor surfaces. Produced from carefully selected raw materials for consistency
of product, it only requires the addition of water on site.
 Application can be by means of 'hand-mix' or by automated pumping equipment - the
final floor finish being smooth, durable and designed to accept various floor coverings
such as vinyl sheeting and -tiles, laminates and marmoleum, rubber floors, carpeting,
parquet, epoxy or urethane coatings and ceramic/porcelain tiles.
 General
Floor Self-leveling Screed should not be applied to exterior surfaces when there is a risk of
rain or frost within six hours after application
 Surfaces preparation
The following minimum curing periods must be observed, before application of this
Screeding compound:
 New concrete floors: 28 days
 New screeds: 28 days
 New brickwork: 14 days
Ensure that all surfaces are clean, dry, sound and free from dust, grease or any contamination
that could impair bonding.
Make good any unsound areas and remove flaky or peeling layers before
2.4. Cover and colored paints
2.4.1. Applying cover and colored paints to concrete

Paint is a great way to completely cover concrete with an opaque color. Concrete is easy to
paint and will accept any acrylic latex or oil paint. Special concrete paint is formulated to
withstand abrasions that concrete is likely to incur, however any paint can be applied to a
clean, debris-free concrete surface.
Concrete Floor Refresh
A fresh coat of color solves everything! And it's easy when you can rely on strong, innovative
tools that take the heavy lifting out of painting even a large floor.
Fig.2.9. Concrete Floor Refresh

Concrete is one of the most durable construction materials around, but the characteristic dull
gray of a concrete slab can seem cold and unappealing, especially as flooring. Lucky for
many DIY-inclined homeowners, concrete is also a fairly versatile material that offers many
options for repairs, alterations, and improvements.
The bottom line: If you have concrete floors in your basement, garage, or screened-in patio,
you don’t have to live with lackluster. You can refresh the entire space by painting your
concrete floors.
In combination with the right tools and techniques, today’s masonry paints, designed
specifically for concrete, make it easy to turn a drab concrete floor into an attractive surface
that can complement a variety of spaces, both indoors and out.
Painting concrete surfaces requires more skill, tools, and time than throwing a coat on
drywall. Here’s how to do it right.
Concrete painting is trickier than painting most surfaces: It breathes, transports moisture, and
sucks up paint.
While you can paint drywall in a day or two, you’ll need a week or more to finish painting
concrete. Continue reading below for tips -- plus costs -- on how to paint concrete surfaces:
Fig.2.10. Concrete Painting

2.4.2. Simple 4-Step Guide to Concrete Painting
1. Strip Old Paint
Strip peeling or blistering paint indoors with a wire brush, a paint scraper and lots of
elbow grease.
2. Seal Interior Concrete
Water moves easily through porous concrete, so sealing interior walls is necessary
to prevent moisture from seeping in, promoting mold growth and that cold, damp
basement feel. Use a masonry sealer, such as Thoron Seal, that also patches cracks.
Carefully follow directions for mixing, applying, and curing the sealer. Thoron Seal,
for example, requires two coats; the manufacturer recommends curing for five to
seven days before applying the second coat.
3. Prime the Concrete
Concrete primer, called block primer, fills pores and evens out the surface. For
exterior foundations and walls, use exterior-grade block filler, such as Behr’s
Concrete and Masonry Bonding Primer, which also is good for interior concrete
($17.98 per gallon)? Primer dries in two hours; wait at least eight hours, but no
more than 30 days, to paint.
4. Paint the Concrete
Masonry paint (also called elastomeric paint or elastomeric wall coating) is a good
choice for concrete painting because it contains binders that contract and expand with
the concrete. Exterior house paint can crack and peel on concrete.
2.4.3. Concrete Sealing
Once decorative concrete floors or new concrete colored are finished the best way to
keep them looking great is to seal and protect their surface. Parched supply some of
the hardest wearing decorative concrete sealing systems in the world.
It is essential that your decorative concrete surface is resealed periodically in order to
lock in the color, protect the surface from impurities and maintain its glossy appeal
Fig.2.11. Colored Concrete Sealers
I. Colored Concrete Sealers

Dramatically improve the appearance of your concrete by adding a Colored Concrete
Sealer.
The Colored Concrete Sealer system is ideal for coloring and protecting plain
concrete. It is a two part system; Part A the color sealer clear base and Part B the
color tint. The Color Tint (Part B) is added to the Color Sealer Clear Base (Part A),
and then applied using a roller or soft bristled broom
2.5. Maintain or repairing masonry structure

2.5.1. Defects In Masonry Walls
General aspects
Problems with the behavior of buildings normally appear through the occurrence
of defects. The behavior of buildings is quite complex and involves aspects of
material science that sometimes are not well understood yet. Also, masonry is a
subject which is not taught in depth during Engineering and Architecture University
courses. These aspects increase the difficulty in accurately identifying defects in
buildings elements and determining the cause. In general terms, the main causes of
defects are associated with human and natural causes (Table 2.1).
Causes Type Agent
Human Design Improper calculation methods and errors, insufficient technical

actions information and level of detailing, improper design assessment
(loads, local conditions, compatibility between different
functionally aspects…)
Execution Use of bad quality materials, inadequately qualified and
experienced personnel, inadequate execution control of
construction
works, bad interpretation of the project
Utilization No, or inadequate, maintenance procedures, changes in the
utilization, excessive loading…
Disasters Fire, explosion, impact, …
Natural Physical Wind and rain effects, snow, creep, thermal/moisture movements,
actions Chemical Oxidation, carbonation, acid rain, salts…
Biological Vegetation (roots, fungus,...), animals (warms, insec
Disasters Seismic, cyclone, avalanche, flood, volcanic eruption, …)
Table 2.1 - General causes of defects in buildings
2.5.2. Cracking Prevention in Masonry Partition Walls

I. General
Interior walls have as their function the separation between different spaces (rooms).
They don’t have a structural role, so their thickness is generally only 5 to 10 cm. They are
often constructed in brittle masonry materials such as clay bricks or blocks, concrete blocks
(dense or lightweight), calcium silicate units, gypsum, etc. This means that their ability to
adapt to deformations in the building is very low - they are building elements that can be
exposed to cracking in various forms. The cracks have an influence on the aesthetic
function and on some of their physical properties such as noise insulation.
In practice, the cracks in the interior walls can often cause litigation since repair
costs can be very high if properly done.
II.Origin of defects in interior walls (partitions)

Excessive deformation of slabs or beams supporting partitions is the most frequent
cause of damage to partitions. While the beam or slab can deflect without any damage,
the supporting brittle masonry elements cannot follow and will crack (Figure Below).
Fig.2.12. Cracks in a partition due to the deformation of support
The form of these cracks depends on several factors:

 The ratio of length to the height of the wall
 The type and quality of the masonry material in the partition;
 The presence of door and window openings in the partition;
 Any interaction with other walls, partitions, columns, etc.
Different situations may occur.
a) The deflection of the slab on the upper level of the partition is higher than that at the
foot of the partition (Figure below).
Fig.2.13. Cracks in a partition due to the deflection of the upper support
In this case the partition takes on a structural function. It will behave as a deep
beam
under flexure but the partition was not designed for this function so if the tensile
stresses in the partition produced by such a deflection are higher that the tensile strength
of the masonry, cracks will occur (Figure below).
Fig.2.14. Partition is acting as a deep beam in flexure

These are similar to the cracks in a concrete beam under flexure. In reality a new
distribution of the loads occurs with the partition as a structural element. The part of the load
distributed to the partition depends on:
 The stiffness of the partition;
 The rigidity of the partition support;
 The position of the partition in relation to the other supports (walls, beams,
etc.);
 The physical characteristics of the masonry of the partition.
Active Cracks Repairing
Active cracks occur because of thermal movement. These cracks always reoccur after
some time once they are repaired.
1. Repairing of Cracks in Brick Wall (Crack width below 2 mm):
 If the cracks remain under 2 mm in width, then the crack can be repaired with the
snow filla paint (ACC make) that is extended in the cracks after it becomes dry. It is
recommended to cure painted crack for minimum five days.
2. Repairing of Cracks in Brickwork (Crack width among 2 mm to 5 mm):
 If the cracks remain among 2 mm to 5 mm in width, then the crack should be repaired
by injecting the flowing grout in the ratio like cement 1 kg, grout polymer 0.1 kg, and
1-litre water. Bore the hole at a distance of 350 mm c/c for attaching the nipple with
the sealant. The grout mixture is injected with the pressure of 3 kg/cm2 through a
pressure pump.
3. Repairing The Cracks In Brickwork (Crack width among 5 mm To 10 mm):
 If the cracks remain among 5 mm to 10 mm in width, then eliminate all the loose
materials and keep the width of the groove of cracks as 25 mm and depth as 10 mm.
Detach the plaster up to a width of 300 mm on the both sides of the cracks and fill the
groove with CM 1:3 having 10% polymer by weight of cement. Once the cracks are
filled, 12 mm diameter nipples should be inserted at 100 mm c/c and 30 mm to 40 mm
deep along the crack line and employ the above grouting method for grouting the
cracks.
4. Repairing of Cracks in Brick Masonry (Crack width over 10 mm):
 Eliminate all the loose materials from the crack and detach the plaster up to 450 mm
on both side of the cracks. Fill the cracks with CM 1:3 with 10% polymer by weight
of cement.
Self –Check 2 Short Answer writing
Test I: Short Answer writing

1. Why Does Concrete Need Repairing? (5pts)
2. What causes damage to concrete? (2points
3. What is dusting? (3pts)
4. What is Repair of dusting floors(4pts)
5. What is Concrete repair? (5 points)
6. What is Self-leveling concrete is? (3point)
7. What is Painting Concrete?(4point)
8. List Simple 4-Step Guide to Concrete Painting(4point)
Operation Sheet 2
Operation Title Applying cover and colored paints to concrete
Purpose:- To apply quality work and health care

Instruction: - Using the right tools to perform your task within the given time. You have given
50Minut for the task.
Equipment and Tools
 Shovel
 Chisel
 Trowel
 Brooms
 Concrete Saw
 Hammer
precaution:-

PROCEDURE,
Step 1. Wear your PPE properly
Step 2. Select required materials
Step 3. Select required tools and equipment
Step 4. To chisels the repairing surface and Strip Old Paint
Step 5. Seal Interior Concrete
Step 6. Prime the Concrete
Step 7. Paint the Concrete
Quality Criteria: Assured to follow the proper application of Occupational Health and Safety
requirements
Name: __________________________ Date: ____________

Task 1: Apply cover and colored paints to concrete
Unit Three: Carry out rectification of cracks and other major defects
and topics:
● Cause of the defect
● Concrete flexible epoxy pitches
● Applying coverings concrete materials techniques
● Safely requirements
● Replacing and Rectifying masonry structure
● Brushing rusted reinforcement.
● Rectification and reparation timber stair components
● Installing and replacing windows and doors.
This guide will also assist you to attain the learning outcomes stated below. Upon
completion of this learning guide, you will be able to:
 Determine and resolve cause of the defect.
 Prepare Concrete flexible epoxy pitches
 Apply coverings concrete materials techniques
 Apply safely requirements
 Replace and rectify masonry structure.
 Brush rusted reinforcement.
 Do rectification and reparation timber stair components
 Install and replace windows and doors.
3.1 Cause of the defect

3.1.1. Types of Concrete Defects – Causes, Prevention
Various types of defects which can be observed in hardened concrete surface and their
prevention methods are explained below:
I. Cracking
Cracks are formed in concrete due to many reasons but when these cracks are very deep, it is
unsafe to use that concrete structure. Various reasons for cracking are improper mix design,
insufficient curing, omission of expansion and contraction joints, use of high slump concrete
mix, unsuitable sub-grade etc.
To prevent cracking, use low water – cement ratio and maximize the coarse aggregate in
concrete mix, admixtures containing calcium chloride must be avoided. Surface should be
prevented against rapid evaporation of moisture content. Loads must be applied on the
concrete surface only after gaining its maximum strength.
Fig3.1 Cracking
II. Crazing
Crazing also called as pattern cracking or map cracking, is the formation of closely spaced
shallow cracks in an uneven manner. Crazing occurs due to rapid hardening of top surface of
concrete due to high temperatures or if the mix contains excess water content or due to
insufficient curing.
Pattern cracking can be avoided by proper curing, by dampening the sub-grade to resist
absorption of water from concrete, by providing protection to the surface from rapid
temperature changes.
Fig3.2 Crazing or pattern cracking
III. Blistering
Blistering is the formation of hollow bumps of different sizes on concrete surface due to
entrapped air under the finished concrete surface. It may cause due to excessive vibration of
concrete mix or presence of excess entrapped air in mix or due to improper finishing.
Excessive evaporation of water on the top surface of concrete will also cause blistering.
It can be prevented by using good proportion of ingredients in concrete mix, by covering the
top surface which reduces evaporation and using appropriate techniques for placing and
finishing.
Fig3.3 concrete blistering

IV. Delamination
Delamination is also similar to blistering. In this case also, top surface of concrete gets
separated from underlying concrete. Hardening of top layer of concrete before the hardening
of underlying concrete will lead to delamination. It is because the water and air bleeding from
underlying concrete are struck between these two surfaces, hence space will be formed.
Like blistering, delamination can also be prevented by using proper finishing techniques. It is
better to start the finishing after bleeding process has run its course
Fig3.4 Delamination
V. Dusting
Dusting, also called as chalking is the formation of fine and loose powdered concrete on the
hardened concrete by disintegration. This happens due to the presence of excess amount of
water in concrete. It causes bleeding of water from concrete, with this fine particles like
cement or sand will rise to the top and consequent wear causes dust at the top surface.
To avoid dusting, use low slump concrete mix to obtain hard concrete surface with good wear
resistance. Use water reducing admixtures to obtain adequate slump. It is also recommended
to use better finishing techniques and finishing should be started after removing the bleed
water from concrete surface.
Fig.3.5 Dusting
VI. Curling
When a concrete slab is distorted into curved shape by upward or downward movement of
edges or corners, it is called curling. It occurs mainly due to the differences in moisture
content or temperature between slab surface (top) and slab base (bottom).
Curling of concrete slab may be upward curling or downward curling. When the top surface
is dried and cooled before bottom surface, it begins to shrink and upward curling takes place.
When bottom surface is dried and cooled due to high temperature and high moisture content,
it will shrink before top surface and downward curling occurs.
To prevent curling, use low shrink concrete mix, provide control joints, provide heavy
reinforcement at edges or provide edges with great thickness.
Fig3.6: Curling of Concrete Slab
VII. Efflorescence
Efflorescence is the formation of deposits of salts on the concrete surface. Formed salts
generally white in color. It is due to the presence of soluble salts in the water which is used in
making concrete mix.
When concrete is hardening, these soluble salts gets lifted to the top surface by hydro static
pressure and after complete drying salt deposits are formed on the surface.
It can be prevented by using clean and pure water for mixing, using chemically ineffective
aggregates etc. And make sure that cement should not contain alkalis more than 1% of its
weight.
Fig3.7 Efflorescence
3.1.2. Design and construction defects

Defects are not strictly deterioration mechanisms in the same way as those described in
previous sections. These mechanisms should not occur in properly designed, detailed and
constructed structures.
 Incorrect cover
Low cover to reinforcement has two effects on reinforced concrete:
 Durability is reduced –in particular the time to corrosion is reduced, as there is less of
a barrier to carbonation or chlorides
 Bond strength – can be reduced
High cover is also of concern, particularly in cantilevers. If the reinforcement is placed too
far from the tension face, then the lever arm will be reduced, and it will not be effective in
carrying load.
 Low concrete strength
One of the more common defects in some countries is low strength concrete. This can result
from a number of causes, but the prime cause appears to be low cement contents.
Low concrete strength implies a high water-cement ratio (w/c). In addition to low strength, a
high w/c ratio is likely lead to low durability, as the effects of most deterioration mechanisms
are inversely proportional to the w/c ratio.
 Overload
These are not strictly deteriorations mechanisms in the same way as those described in
previous sections. However, the structural mechanisms can lead to cracking if the members
are overloaded.
 Flexure
Flexural stresses result from the bending of a member. These stresses will either be tensile or
compressive depending on the orientation of the member and its loading.
3.2 Concrete flexible epoxy pitches
3.2.1. Epoxy-resin mortar and concrete

Epoxies also come in the category of polymer but in the case the of epoxies, the
polymerization process take place when tow materials called the epoxy resin and hardener
come in contact by thoroughly mixing in specified proportion.
The epoxy resin materials have good mechanical strength, chemical resistance and ease of
working.
Field of applications:
3.2.2. Anti-corrosive and water proofing coatings: Fusion bonded epoxy powder (FBEP)
coatings are being used for protection of reinforcing bars against corrosion in RC structures
located in highly aggressive areas. FBEP process provides a tough film, which can withstand
bar bending without cracking.
Bond coats and grouts: Epoxies are used as bond coats and grouts due to their excellent
adhesive qualities on cementations as well as metallic surface. An epoxy film is brushed or
sprayed onto the surface of the cleaned substrate and the new concrete is placed as the epoxy
becomes tacky but before it hardens.
Structural repair to concrete: Due to their excellent mechanical properties and bond
characteristics with most of the materials, epoxy mortars / concretes are used to make up the
damaged or lost cover concrete, etc.
3.2.3. Applying flexible Epoxy Resins
Epoxy resins cure to form solids with high strength and relatively high modulus of
elasticity. These materials bond readily to concrete and are capable, when properly applied,
of restoring the original structural strength to cracked concrete.
The high modulus of elasticity causes epoxy resin systems to be unsuitable for rebinding
cracked concrete that will undergo subsequent movement Cracks to be injected with epoxy
resins should be between 0.002 inch to 0.25 inch in width.
It is difficult or impossible to inject resin into cracks less than about 0.002 inch in width,
and it is very difficult to retain injected epoxy resin in cracks greater than 0.25 inch in width,
although high viscosity epoxies have been used with some success.
Epoxy resin bond strengths can easily exceed the shear or tensile strength of the concrete. If
these materials are used to re bond cracked concrete that is subsequently exposed to loads
that exceed the tensile or shear strength of the concrete, cracks will likely recur adjacent to
the epoxy bond line. In other words, epoxy resin should not be used to re bond “working”
cracks
Epoxy resins will bond with varying degrees of success to wet concrete. There are a number
of special techniques that have been developed and used to re bond and seal leaking cracks
with epoxy resins. These special techniques and Procedures are highly technical and, in most
cases, are proprietary in nature.
They may have application on Reclamation projects, but only after a thorough
Analysis has been performed to ensure that the more standard repair procedures
will not be successful or cost effective.
Fig3.8.1High-volume water leaks can be repaired using Epoxy resins
 Epoxy resin systems
Epoxy resin systems can be formulated in many ways, depending upon the ultimate
properties, application characteristics and in-service conditions.
The most commonly available systems are:
(i) Solvent/water based: These systems are normally formulated with ease of application in
mind or, in the case of water based epoxies; the overriding factor is one of health and safety
or environmental factors.
These systems are normally low film build as they rely upon the evaporation of the carrier
(solvent or water) to affect the cure of the system. These systems are normally used for non-
immersion applications due to their high permeation rates and are more commonly referred to
as 'paints' rather than coatings.
Limitations
 Low film builds.
 Considerable shrinkage during cure.
 Extended cure times.
 Susceptible to blistering in immersion conditions due to solvent entrapment.
 Limited immersion temperature resistance.
(ii) Solvent free epoxy resin systems: These materials are designed to have high mechanical
strength and have negligible shrinkage. Pigments and fillers are also used in these types of
resin systems to perform specific functions, as well as provide a barrier to liquid ingress.
Fillers include spherical, lamellar and mixed particle shapes to increase corrosion resistance,
abrasion resistance and erosion resistance.
 Limitations
 Low reactivity at low temperatures.
 High viscosity and poor application characteristics.
 Limited immersion temperature resistance.
3.3 Applying coverings concrete materials techniques

3.3.1. Concrete structure repair materials
There are various types of materials which are used for the repair of concrete structures. For
instance, unmodified Portland cement mortar or grout, latex modified Portland cement mortar
or concrete, quick setting non-shrink mortar, and polymer concrete. The choice of such
materials is based on their performance and cost. In addition to repair material compatibility
with damaged structure and ease of application.
Selection Criteria for Repair Materials

 Ease of application
 Cost
 Available labor skills and equipment
 Shelf life of the material
 Pot life of the material
 Type of damage
 Compatibility of the repair material with damaged concrete
 Appearance of finished surface
 Co-efficient of thermal expansion of the material
 Co-efficient of permeability of the material
 Corrosion resistance property of the material
 Durability of such concrete repair material
 Speed of concrete repair
Common Repair Materials

Following are the some of the common repair materials used for repair or rehabilitation or
strengthening of the concrete structures:
1. Unmodified Portland cement Mortar or Grout
Portland cement mortar or grout is the most common repair materials used for repairing
damages to concrete structures. It is selected because it is readily available and has a low
cost.
This material consists of ordinary Portland cement and suitable aggregate. Cement mortar is
generally used for small repair works and cement concrete are commonly selected where a
large area is to be repaired.
Fig.3.9: Unmodified Portland cement Mortar
2. Latex Modified Portland cement Mortar or Concrete
This repair material is used to prevent chloride attack on concrete structure due to the use of
low water-cement ratio. This is the same as ordinary Portland cement mortar or grout with the
addition of a latex emulsion. The strength of this material is same as ordinary mortar or grout.
Ingress can be reduced due to lower water-cement ratio.
The addition of latex modifier influences the strength and durability of cement. The use of
this material should be based on the service conditions of the structure.
Latex modifier concrete recommended for sections up to 30mm deep should have 1:3-3.5 as
the ratio of cement and fine aggregates. Water ratio should be 0.3 with latex solid cement
ratio of 0.1 to 0.2 by weight. Latex modifier concrete recommended for sections deeper than
30mm should have proportions of 1 part of cement to 2.5-3 parts fine aggregate to 1.5-2 parts
coarse aggregate.
Fig3.10: Latex Modified Mortar
3. Quick Setting Non-shrink Mortar
Cracks on concrete surface due to shrinkage of concrete are repaired by this material. It
develops a good bond with old concrete. The use of suitable admixtures combined with this
repair material also increases strength and improve bond and workability while reducing
curing time.
Fig3.11: Quick-set Non-shrinking Mortar
3.4 Cleaning Safely requirements

3.4.1. Cleaning Concrete
How-to tips for cleaning your concrete slabs, floors, and counter tops Cleaning concrete
periodically will extend its service life and enhance its beauty. It can be difficult to tell when
concrete is in need of cleaning because the dirt and grime can build up so slowly. However,
once the process is done, the results of freshly cleaned concrete are very noticeable.
There are multiple ways to clean concrete depending on the type of surface, such as exterior
slabs, floors or countertops. Each requires a different procedure to avoid damaging surfaces.
Fig .3.12.Avoid damaging the surfaces.

Cleaning an old concrete slab so it will take an acid stain can be very difficult, but it is
possible. The main thing is to NOT use any kind of acid wash or etching solution (including
muriatic acid) to clean the slab. The stain will not take at all if you use acid as a cleaner.
A solution of TSP (tri sodium phosphate) and a lot of elbow grease with a scrub brush would
be your best bet. Using a scrub brush with a long handle makes cleaning much easier.
Another option would be to use a pressure washer to clean the concrete slab. For grease stains
on concrete, try scrubbing the stain with lacquer thinner or mineral spirits.
Even with your best efforts, you may wind up with patches on a concrete slab that simply
won’t take an acid stain due to low lime content in the concrete (lime is what causes a
chemical reaction with the acid stain). In those cases, you may have to resort to applying a
faux finish to the spots to try and match the acid stain in the surrounding areas.
Concrete Acid Stain is a water-based liquid bearing minerals and acid. The acid stain
penetrates the pores of the concrete forcing a chemical reaction between the muriatic acid
and the available lime in the surface. Once acid stained, the color of the concrete is
permanently altered. When sealed with an appropriate concrete sealer and for indoor
applications, sealed and waxed, acid stain produces the unique, variegated finish associated
with this process.
 Before Acid Staining: Surface Preparation
Surface preparation is the most important step in the acid staining process. Prior to staining, a
slab must meet the following criteria:-
 The concrete must be free of debris, dirt and oils, paint, dry wall mud, adhesive,
sealers, stains of any kind or similar materials. Acid stain cannot react properly with
the concrete if these conditions are present.
 The slab should not have been treated with a waterproofing agent, cleaned with
muriatic acid or a heavy trisodium phosphate (TSP) solution. The acid stain reaction
cannot occur on surfaces treated with these products
 Newly poured concrete can be acid stained anytime from 20-28 days after the pour or
once the concrete has achieved a uniform light gray color.
 For older, excessively power-washed, or mechanically-profiled concrete, the surface

must be completely intact with no exposed aggregate or sand particles. Concrete acid
stain does not stain rocks, sand or aggregate.
Exposed aggregate or otherwise depleted concrete may cause the acid stain to take
irregularly, react weakly or produce a color inconsistent with the acid stain color chart
 Slick, machine-troweled concrete requires mechanical or chemical etching for a

complete acid stain reaction to occur. If water beads on the surface or dark gray areas
caused by excessive troweling are visible caused by excessively troweling, DCI Hard
Troweled Floor Prep should be sprayed on the concrete or the surface should be
sanded using an 80-grit sanding pad prior to application.
 Newly poured concrete slabs and countertops should include less than 10% fly ash to
insure a good chemical reaction with the acid stain. Check with your ready mix
company or read the countertop mix MSDS for concrete additive information.
 Concrete poured with excessive water in the mix can create a thin, unstable layer of
concrete on the slab surface. To test for instability, press the tip of nail into the
concrete. If breaking or damage of any kind occurs, the slab must be profiled with a
concrete grinder or a high-speed buffer using a 60-80 grit sanding disc before
staining.
How to care for concrete floor
No type of flooring material is truly maintenance free, and the same holds true for decorative
concrete. Concrete floors are relatively easy to care for when compared with other types of
flooring, especially carpet, but they do require regular attention. How much maintenance
your floor will need largely depends on the amount of traffic it receives.
Some of the many maintenance-related advantages to concrete flooring are:
 No joints, grout lines or fibers to trap dirt.
 Stain, water, and abrasion resistant when properly sealed.
 Pet-friendly, easy clean-up for muddy paws and accidents.
 Simple cleaning of dry or damp mopping.
 Minimal routine maintenance of reapplying sealer every few years.
How to clean concrete floors
People who have concrete flooring love how quick and easy it is to clean. The basic steps are
as follows:
1. Dry mop daily to remove dirt and debris
2. Damp mop with a pH-neutral cleaner as needed
3. Clean spills from the floor as quickly as possible so they don't stain the surface
Fig3.13.clean concrete floors
3.5 Replacing and Rectifying masonry structure
3.6 Brushing rusted reinforcement
3.7 Rectification and reparation timber stair components
3.8 Installing and replacing windows and doors
Self-Check 3 Short Answer writing
Test I: Short Answer writing

1. Write the Types of Concrete Defects – Causes, Prevention [4pts]
2. What is cracking (4pts?)
3. What is Epoxy resins (4pts)
4. Write the Common types of Repair Materials? (5pts)
5. Write the Selection Criteria for Repair Material? (2points)
6. What is cleaning? (5 points)
7. Write basic step clean concrete floors? (3point
Operation sheet 3
Operation Title Cleaning concrete floors
Purpose:- To care for concrete floor

Instruction: - Using the right tools to perform your task within the given time. You have
given 10Minut for the task.
Equipment and Tools
 Shovel
 Chisel
 Trowel
 Concrete Saw
 Hammer
 Wire brush
 Broom
 Bucket
precaution:-
 The required drawing or plan
Procedure:-
Step 1. Wear your PPE properly.
Step 2. Prepare all the necessary material & equipment
Step 3. Dry mop daily to remove dirt and debris
Step 4. Damp mop with a pH-neutral cleaner as needed
Step 5. Clean spills from the floor as quickly as possible so they don't stain the surface
Quality Criteria: Assured to follow the proper application of Occupational Health and Safety
requirements
Name: __________________________ Date: ____________

Task 1: Clean concrete floors
5. Unit Four: Clean up
and topics:
● Clearing work area
● Disposing , reusing and recycling materials
● Cleaning, checking, maintaining and storing plant, tools and equipment
This guide will also assist you to attain the learning outcomes stated below. Upon completion of
 Clear work area
 Dispose, reuse and recycle materials
 Clean, check, maintain and store plant, tools and equipment
4.1. Clearing work area
A clean, well-ordered, attractive work environment sets the tone of your establishment. It
encourages tidy work habits in employees. It helps reduce fatigue. It promotes good worker-
management relations. It also gives a lift to morale, which is reflected in the quality of
production and overall efficiency. Good housekeeping is also a good advertisement for your
company. Customers and clients have more confidence in an organization when they we
work being carried out efficiently in clean, pleasant, well ordered surroundings. There’s an
even more important reason why good housekeeping matters — it makes the undertaking a
safer place to work in
4.1.1. Keep Floors Clean
Every year thousands of work injuries are caused by people falling. Floor conditions are
responsible for many of these accidents. When floors are given the right treatment they are
much easier to keep clean and hygienic.
Spilt oil and other liquids should be cleaned up at once. Chips, shavings, dust, and similar
wastes should never be allowed to accumulate. They should be removed frequently, or better
still, be suitably trapped before they reach the floor
4.2. Disposing, reusing or recycling material
Definition
Disposing Removing and destroying or storing damaged, used or other unwanted
domestic, agricultural or industrial products and substances
Recycling means turning an item into raw materials which can be used again, usually for
a completely new product. This is an energy consuming procedure
Reusing refers to using an object as it is without treatment. This reduces pollution and
waste, thus making it a more sustainable process.
Purpose
When looking into environmental sustainability, cutting consumption or reducing rubbish
during a house clearance, it’s more than likely that you’ll come across the following 3Rs:
reduce, reuse and recycle. Learn how Disposing, reusing(R), and recycling(R) can help
you, your community, and the environment by saving money, energy, and natural
resources.
Recycling is the process of collecting and processing materials that would otherwise be
thrown away as trash and turning them into new products. Recycling can benefit your
community and the environment.
Recycling reduces waste disposal by transforming useful materials such as plastic, glass
and paper into new products
The reusing process is not just about re-purposing materials, but the object as it is. This
includes buying and selling used goods and repairing items rather than discarding them.
Reusing is better than recycling because it saves the energy that comes with having to
dismantle and re-manufacture products. It also significantly reduces waste and pollution
because it reduces the need for raw materials, saving both forests and water supplies.
Waste that cannot be reused or recycled in some form eventually finds its way to disposal.
This disposal includes landfills, but an increasing number of municipalities have elected to
divert waste into resource recovery. These recovery methods use the waste to generate
electricity or produce raw materials for industry
4.3. Cleaning, checking, maintaining and storing plant, tools and

equipment
4.3.1. Cleaning of Tools and Equipment
Tools and equipment used at the construction site undergo rigorous handling. From initial
foundation development, to the final construction of the exterior trim, these tools are
exposed to large amounts of dirt and abuse. Proper maintenance of construction tools and
equipment is critical to preserving them for future construction jobs. Failure to maintain
the tools properly results in unnecessary expense.
Clean the construction tools and equipment after each day's work. While a thorough
cleaning is not required each day, a general wipe-down and removal of the heaviest
construction dirt is key to extending the life of the tools.
4.3.2. Checking Hand tools
 Mechanical failure or loss of control when using a tool with defective parts.
Examples of unsafe tools are hammers with loose or damaged heads, screwdrivers with
broken handles or blunt edges, chisels with mushroomed heads, and blunt saws.
4.3.3. Checking Power tools
 Malfunctioning of safety devices such as emergency button (red button), protective covers,
guards, etc. In case of emergency these devices will not work properly or will provide
limited protection to the worker, which in some cases can be worse than no protection at
all because it gives a false sense of security.
 Risks of electrocution, shock or burns due to electrical malfunctions, torn cables and lack
of proper insulation or proper earthing.
 Cracked or broken grinding wheels or cracked blades can cause injuries. E.g. cracked
abrasive wheels could fly apart in operation, which could lead to serious injury or death.
 Emissions of chemical substances such as toxic fumes or dust, etc.
 Noise and vibration emitted by almost all portable tools that can lead to hearing loss and
hand–arm vibration syndrome respectively. Vibration can cause “white-finger” disease,
which arises from damage to the muscles and nerves that control the blood flow. Poorly
maintained tools can cause a significant increase in noise and vibration emissions (e.g. a
cutting tool that is not sharp emits higher levels of vibration). Also, damaged anti-vibration
mountings in a tool can increase transmission of vibration to the worker.
4.3.4. Maintaining and storing of tools and equipment
Lubricate air tools and pneumatic equipment before each day's use. Condensation in the
airline creates an environment for corrosion inside pneumatic tools. Coating the internal
components of these tools with air-tool oil will displace the moisture and prevent tool
corrosion.
Inspect and repair all construction equipment and tools at the completion of each job.
Make all repairs to the equipment that are necessary for future construction work. This
will prevent time being wasted repairing faulty equipment at future construction job sites.
Self-Check 4 Multiple choice
Instruction: Select the best answer and encircle the letter
1. What is the advantage of reusing and recycling construction products

A/ Avoids waste
B/Reduces waste
C/Saves primary resources

D/ All of the above are correct
2. -------is contribute to more sustainable development by eliminating or reducing waste
A/ Recycling
B/ Technology
C/ Learning
D/ All of the above

3. What is the dis advantage if someone left Keeping Floors Clean?
A/ It will be attractive
B/ It will be good for working
C/ It will be caused of people falling
D/ All of the above
4. Which one is true about clear area?
A/ It will be benefit by providing safe working area
B/ Expense will be saved
C/The working area and learning classes will be a better place in which to
work
D/ All of the above
5. What is the advantage of maintaining construction tools and equipment?
A/ Increase the service life of the equipment
B/ The performance of the equipment
C/Decrease the price of the equipment
D/ A & B are correct
6. Why we maintain construction tools and equipment?
.A/ Because it make tools and equipment good performance
B/ Because tools and equipment suffer a lot of wear and tear
C/ Because working with broken tools and equipment lead to injure
D/ All of the above
Note:
 Satisfactory rating – above 3 points
 Unsatisfactory - below 3 points
Test II: short Answer writing

1. why we dispose waste materials?
1. Mention at least two points about the advantage of cleaning of tools and equipment
2. Write the benefits of recycling of waste materials
Reference
1. /stnemucoD yrarbiL/stnemucod/dorp_simi/ua.moc.aacc.www//:sptth C
.2 gnitniap/ledomer/moc.cigolesuoh.www//:sptth - etercnoc/gnithgil - /gnitniap
BYCA=frsxs?hcraes/moc.elgoog.www//:sptth
651:wWy5ryiH4E5UH8REWVLV5oO0iUHQNG
+gniylppA+si+tahw=q&1793390499
Participants of this Module (training material) preparation
No Name Qualification Field of Study Organization/ Mobile number E-mail
(Level) Institution
1 Tesfaye Assegidew Msc Construction Mgt Butajira PTC +251913442444 tesfayeassegidew@gmail.com
2 Melsew Keba Msc Construction Mgt Assosa PTC +251913283335 melsewkeba@gmail.com
3 Dawit showafera Msc Construction Mgt DDPTC +251986314667 dawitshowafera835@gmail.com
4 Muluken Solomon Msc Construction Mgt Batu PTC +2519-12289146 mulecot99@gimal.com
5 Tiruneh Asebe Msc Construction Mgt Hossana PTC +251911422557 tirunehasebe@gimial.com

Structural Construction Works Level - Ii: Based On March 2022 Version-I Curriculum

Uploaded by

Copyright:

Available Formats

Structural Construction Works Level - Ii: Based On March 2022 Version-I Curriculum

Uploaded by

Document Information

Original Description:

Original Title

Copyright

Available Formats

Share this document

Share or Embed Document

Sharing Options

Did you find this document useful?

Is this content inappropriate?

Copyright:

Available Formats

Structural Construction Works Level - Ii: Based On March 2022 Version-I Curriculum

Uploaded by

Copyright:

Available Formats

STRUCTURAL CONSTRUCTION

Module Title: - Repair and Rectify Structural

TTLM Learning Materials

In structural construction work; Repairing and Rectifying Structural construction work

1.1 Work Instruction

1.2 Safety plans and policies

1.2.2. What Safety Means

 Safety means a complete understanding of your work and knowledge of every

Maintaining a safe and healthy working environment.

Preventing fatalities and lost time injuries.

Preventing damage to the equipment, facilities and potential effects on

Eliminating risk to the environment.

No fires. A Safe and Productive Project, in Scheduled time.

1.2.4. Safe Work Method

1. Fall from heights is the predominant causes of accidents

2. Lack of supervision for workers working at heights

3. Workers lack awareness on OSH

4. Workers have limited trainings

5. Due to lack of training, workers

 Build improper temporary structures

1.3 Signage/Barricade Requirements

1.3.1. Sign requirements

1.3.2. Types of barricading

Fig.1.2. Solid barricades:-

Warning / Safety Signs

1.3.3. Standard Color of Signs

Fig.1.3. Fire Protection

SAFETY GREEN: DESIGNATING SAFETY

Fig.1.4 .Safety Green Designating Safety

Fig.1.5 Safety Yellow Caution

SAFETY ORANGE: ALERT

Fig.1.6. Safety Orange: Alert

SAFETY BLUE: PRECAUTION

Fig.1.6. Safety Blue: Precaution

Where Signage are Needed

 Usage of PPE prior to entry to the project site

1.4 Tools and Equipment

Construction are listed below

1. Blower: an air compressor that produces air at low pressur

4. Brush and Broom

Fig.1.8.Broom Fig.1.9. Hand broom or brush

Fig.1.11. Wheelbarrow /85Lit

Fig.1.12. Angle grinder

1.5 Calculate Material quantity

1.6 Materials Handling

Acrylic Concrete and Mortar

Essential parameters for repair materials

Criteria for selection of repair materials

Fig.1.14. Possible loads acting on a repair

There are a number of advantages to undertaking environmental management and these

1.7.2. What is an Environmental Policy?

(e.g. on quality and on health and safety).

Each of these benefits is now examined below:

Improving the efficiency of existing processes

Introducing more efficient processes

It may be possible to redesign a product so as to reduce the amount of resources it contains

Waste Disposal - Making Money from Waste

Sourcing of Raw Materials

Name: ______________ Date:

Name: ______________ Date: