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Internship report 2021

Table of Contents page


ACKNOWLEDGEMENT............................................................................................................II
Executive Summary.................................................................................................................III
Chapter One...............................................................................................................................1
1.1 Introduction to Internship.................................................................................................1
1.1.1 General......................................................................................................................1
1.2 Background of the company............................................................................................3
1.2.1 History of the Company............................................................................................3
1.2.2 History of consultant sides........................................................................................3
1.3 Background of the Project................................................................................................6
1.3.1 Introduction to the Project Contractual matters........................................................7
1.3.2 Contract Data and Project Information.....................................................................8
1.3.3 Organizational Chart for the Project Staffs.............................................................11
Chapter Two.............................................................................................................................12
2.1 Overall Internship Experience........................................................................................12
2.1.1 How I Get to the Company.....................................................................................12
2.2 Work section I participated in The Company................................................................12
2.2.1 Site work or Fieldwork............................................................................................13
2.2.1.1 Site investigation............................................................................................15
2.2.1.2. Surveying........................................................................................................17
2.2.1.3 Earth work & construction of pavement........................................................19
2.2.1.4 Construction of structures...............................................................................30
2.3 Work tasks I have been executing.............................................................................33
CHAPTER THREE..................................................................................................................35
3.1 Benefit of the internship............................................................................................35
CHAPTER FOUR....................................................................................................................37
4.1 Recommendation and conclusion..................................................................................37
4.1.1 Recommendation.....................................................................................................37
Reference………………………………………………………...............................39
Internship report 2021

Figure of Contents page


Fig 1. Start of road at Sta. 0+000 upgrading 13
Fig 2. Alignment passing urban area 13
Fig 3. Area of proposed intersection 14
Fig 4. Sign along road warning 14
Fig 5. Gasuba by-pass require intersection 14
Fig 5. Animal crossing road 14
Fig 7. Steep grade and sharp bent approach bridge………...…………………………….….14
Fig 8. Sign warning of sharp bent……………………………………………………………14
Fig 9. View of triple span bridge……………………………………….……………………15
Fig 10. Deck slab holes on the superstructure……………………………………………….15
Fig 11. Existing pipe vegetation overgrow…………………………………………………..16
Fig 12. Existing pipe culvert half silted……………………………………………………...16
Fig 13. Surveying practice…………………………………………………………………...17
Fig 14. Recorded data…………………..……………………………………………………19
Fig 15. Plotting LHS,CL,RHS……………………………………………………………….19
Fig 16. Clearing and Grabbing……………………………………………………………….21
Fig 17. Sub grade lay…………………………..…………………………………………….22
Fig 18. Sub base layer……………………………………………………………………......24
Fig 19. Box culvert…………………………………………………………………………..31
Fig 20. Two cells pipe culvert……………………………………………………………….32
Fig 21.Bridge 20m spam …………………………………………………………………….33
Internship report 2021

Tables page
Table 3.1 Project geometric control point…………………………………………………20
Table 3.2 Embankment material specification……………………………………………..22
Table 3.3 Minimum acceptable density……………………………………………………23
Table 3.4 Construction tolerance…………………..………………………………………23
Table 3.5 Grading requirement for sub base material………….…….…………………….24
Table 3.6 Type-B granular sub base material satisfy………………..……………………..25
Table 3.7 Aggregate for Asphalt & Bitumen binder………………...………..………..27&28
Table 3.8 The temperature of storage………………………………………………………29
Table 3.9 Temperature range of bituminous………………………..………………………29
Internship report 2021

ACKNOWLEDGEMENT
First I would like to thank GOD for the accomplishment of this internship program. Next I
would like to express my deepest gratitude and respect to my advisors Mr. Samuel Tesfaye
from the company and Mr. Aliyu from the university for valuable advice and in providing
relevant hint and encouragement for the completion of this work. I also want to thank my
families and my brother Resom Getachew for supporting me while doing this research.

Finally, I would like to say I am forever in debt to the all consultant and contractor side staff
members for their willingness to give me and sharing their knowledge.
Internship report 2021

Executive Summary
Sodo-Dinke section of the Jimma-Chida and Sodo-Sawla Road upgrading Project (Lot 2) as a
whole is located mainly in Wolayta and Gamo Gofa Zones of the Southern Nations,
Nationalities and People Regional State. The road starts at Sodo Town and proceeds via
South West part of Welayta Zone to Gamo Gofa Zone. This road linked to Addis-Sodo-
Arbaminch trunk road, lying in South part of the Country. The total length of project road is
about 86.3kms. After its completion, the upgraded road will facilitate the socio-economic
aspect of the Country in general and the Region in particular.

The economy in the project road corridor is dependent on small holder farming and livestock
keeping. Farming activities are practiced by using traditional hand tools and oxen plough.
The project area suffers from repeated drought, population pressure, shortage of rain falls and
arable land, soil degradation, and other factors. In general, the project road corridor is known
for its low level agricultural production.

The company performs and constructs many things from that

 The construction of road


 The construction of bridge
 The construction of water way by pipes, box culverts
 The construction side ditch
 The construction of walk way
Chapter One

1.1 Introduction to Internship

1.1.1 General

First of all, I would like to explain the importance of the internship. An Internship program is
a short term as we all know but it gives as a short-term professional experience. Students
work a minimum of 8(eight) hours per week or a maximum of 40(forty) hours per week or
we call it full time for one academic term (one semester). The activities are performed by a
professional’s guidance and supervision of staff members. Within this short period, students
gain so much new information’s also new ideas and knowledge that put a lot of interest in the
student's minds to love their profession and are more interested to know much about their
field.

This experience not also gives the theoretical knowledge but also how to interact and
communicate with other people because in engineering teamwork has a big value than
individual work.

Overall an internship program gives the student a lot of advantage from these advantages

 Personal: - when we say personal the students can compare and integrate the theoretical
knowledge with actual work experience and it also increases the students’ eagerness to
know and to learn further academic knowledge and experience. Not also that they gain
teamwork abilities, self-confidence; they will be open-minded and also understand what
will be expected of them when they begin work as a professional.
 Academic: - within this process students increase and widen their academic knowledge
from the resource not available on campus.
 Professional:- for the professionals also this internship also a good opportunity to refresh
their knowledge

To say the internship is successful the participants are three the University, the Organization,
and also the Student itself

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From the University. The university should

Communicate with the organization or company


Follow-up the student's attendance properly
Submit the cost money with the adjusted date on time
Check the advisors whether they meet with the students
Make a law that every student have to attend all the working week because students
have to know what is expected after graduation how to work in a professional career

From the organization or company. The company

Should have to be open-minded


Give their time with the students
Give tasks to the student to know it better
Communicate with the university
Make things easier and understandable to the students
Check the student's attendance properly

From the students. The student

Have to be interested
Eager to know something
Have to ask question
Have to be punctual
Communicate with the members
Not to say I know rather say tell me even if you know it

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1.2 Background of the company

1.2.1 History of the Company

The company name is Ethiopian Roads Authority (ERA) who accepted my internship
request. The Road Authority (RA) was established by an act of Parliament No. 3 of 2006.
Under this setup, the Minister of Transport and Public Works represents the Government as
the ultimate owner of the national road network. The road Authority (RA) falls under the
Minister, and comprise a Board with a Secretariat.

Vision
To assure the most economic and social benefits of the customers by joining the Ethiopian
road network to middle-income countries in 2023.

Mission
By sustainably expanding, improving, and maintaining the road network timely with quality
and less cost, provides a quality road to Ethiopians to contribute meaningful support for the
universal development of the country.

Objective of Road Section Development Program (RSDP)


Improve transport operating efficiency and reduce road transport costs for freight and
passengers to encourage production, distribution, and export;
Provide access to previously neglected food-deficit rural areas to support efficient
production, exchange, and distribution throughout the country, and
Develop the adequate institutional capacity of the road sub-section both at central as
well as regional level.

The company is not Ethiopian Roads Authority (ERA) of course because ERA is the
Employer of the Project under ERA the working companies are the Consultant and the
Contractor both of them are accepted me to work with them

When we see their histories. First consultant side


1.2.2 History of consultant sides

Under the project, there is two consultant company working with Joint Venture because it is
un international project one from the Sudan company called NEWTECH Consulting Group
Co., Ltd. and the other is Local company called Net Consult Consulting Engineers and
Architects PLC let we see their backgrounds

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NEWTECH Consulting Group CO., Ltd
Newtech Consulting Group (Ltd) was established in 1983 by a group of highly qualified
professionals of diversified engineering, industrial and business experience

Vision
Newtech is the pioneer in the consulting engineering service and one of the most important
firms in Africa and the Middle East operating in the field.

Mission
They seek to provide a variety of high-quality service by highly qualified, well-trained, and
fully loyal professionals working in an attractive environment that is up-to-date with the
evolution of technology while expanding locally and globally to achieve sustainable growth
of our owners’ equity in full compliance with corporate governance and social responsibility.

LINES OF ACTIVITIES
Newtech provides integrated consultancy service in the following field:

1. Transport (Road &Bridge, Railway; Marine, River & Airports; Pipelines)


2. Industry (Agro-industry, Food Processing, Textile, Chemical, and Manufacturing)
3. Agriculture & Irrigation.
4. Water Supply & Sanitary Engineering
5. Buildings & Physical Planning
6. Rural Development
7. Environment

The scope of service provided in such field includes

Project Identification, Feasibility Study, Design, and Preparation of Performance


Specification, Preparation of tender Document, Assistance in Tendering, Supervision of
Construction and Erection, Rehabilitation Study, and Others.

Net Consult Consulting Engineering and Architects PLC


Net Consult Consulting Engineering & Architects plc. Is one of the engineering consultancy
service provides in Ethiopia. The firm offers multi-disciplinary and integrated consultancy
services.

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The firm is owned and founded by three Multidiscipline Civil Engineers and two Architects
on a shareholding basis. Having more than 270 employees in Construction Supervision &
Design activities in Engineering and Architectural Works, the company is currently handling
service worth annual turnover of more than 82.5 million birrs.

Major Objective of the Firm


 Provision of required professional services for engineering construction activities
 Working on Savings in the construction economy
 Adaptation of new engineering and construction
 Playing a significant role in national development
 Finally, all work is to be done by the contractor the name of the companies is
China Railway Seventh Group Co., Ltd (CRSG).

1.3 Background of the Project

SODO-DINKE ROAD PROJECT

LENGTH: 86.3KM COST: ETB BIRR= 1,054,003,610.30

ESTIMATED COMPLETION DATE: 13/05/2022

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EMPLOYER: ETHIOPIAN ROAD AUTHORITY

FINANCER: THE FEDERAL REPUBLIC OF ETHIOPIA ETB 210,800,722.06

THE AFRICAN DEVELOPMENT FUND USD 36,613,079.76

CONSULTANT: NEWTECH CONSULTING GROUP CO., LTD IN JOINT WITH

NET CONSULTING ENGINEERS AND ARCHITECTS PLC

CONTRACTOR: CHINA RAILWAY SEVENTH GROUP CO., LTD

1.3.1 Introduction to the Project Contractual matters

First the Soda-Dinke project is entirely in Southern National and Nationalities people
Regional State (SNNPRS). The proposed road-upgrading project basically follows the
existing alignment. The Sodo-Dinke road section starts at Sodo town and passes through the
town of Gasuba, Selamber and ends at Denki village. The contract includes the construction
of Gasuba town by pass. The project starting point is at Wolayta Sodo town located at about
330KM from Addis Ababa through Hossana or 390KM through Shashemene from Addis
Ababa.

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The Work under this Contract consists of the construction of 86.3Km road to DS-4 standard.
Which is upgrading of the existing gravel road to all-weather high standards two-lane Asphalt
Concrete Surface road, each lane having a width of 3.5m and shoulder width of 1.5m of both
sides at the rural section. Also, the contract includes the construction of a four-lane
carriageway having a 3m and 3.5m width at the main towns of Wolayita Sodo (0+00-3+500),
Gasuba (28+550-30+00), and Selam-Ber (64+400-67+500). In these towns, the contracts also
include 2.5m parking lane and 3.5m pedestrian Walkway, covered concrete side ditch at both
sides; and 2m Median at the center. In the village of Gerera (7+400-10+100), Bishe (24+500-
25+000), and Dinke (70+500-71+500), for these villages the contract includes the
construction of two-lane asphalt concrete having a width of 3.5m shoulder 2.5m and covered
concrete side ditches at both sides of the road.

The project also include construction of 7 bridges, 19 box culverts, 5 slab culverts, 139 pipe
culverts, and other drainage facility and auxiliary needs. The start of the project, Wolayita
sodo town located approximately Northing 756250 and Easting 362500 on the other hand the
end of the project, Dinke village is located approximately at Northing 711228 and Easting at
321031.

The project is funded by the African Development Fund. Contract Agreement for the Work
Contract was signed on the 26th of December 2017 between the Ethiopian Roads Authority
(ERA) and China Railway Seventh Group Co., LTD to perform the Construction work of the
project for the sum of ETB 1,054,003,610.30 including 10% contingency, specified
provisional sums, and 15% VAT.

The Contractor was given Notice to Commence the work on the 14th of May, 2018 through
the Engineers letter Ref.no JV/NEWTECH-NET/SDRD/OFFICE/018/015.Accordingly, on
the 14th of May 2018 is recorded as the effective commencement date, as per the GCC
mobilization period end 15th of September-2018. The Original Period is 48months plus 12
months of defect liability period.

On the other hand, NEWTECH CONSULTING GROUP in a joint venture with Net Consult
Consulting Engineering and Architects PLC for the construction supervision of this project
and Contract Agreement were signed between the Ethiopian Roads Authority and the
Consultant on 30th day of March 2018.

The mobilization period is four months from the commencement date of the works Contract
on 14th May 2018.

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The consultants and the contractor's contractual matters, detailed project description, a typical
section of the project geology of the project route, Major and Minor drainage structures
quantity and location, rainfall, and temperature condition of the area are studied

1.3.2 Contract Data and Project Information

Project Name Lot 2 Sodo -Dinke Road Project


Southern Region – 86.3 km
Location /Length Sodo:- N (756250), E (362500)
Dinke:-N (711228), E (321031)
Employer Ethiopian Road Authority ERA
Funding Agencies African Development Fund (80%), FRE (20%).
Joint Venture Newtech Consulting Group- Net
Supervision Consultant
Consulting Engineers PLC
Contractor China Railway Seven Group LTD
Contract Amount ETB 1,054,003,610.3
Foreign Component ($) 80% (US Dollars)
Contract signature date 28th November 2017
Period of commencement from the
120 Days
Engineer’s order to commence work
Commencement date 14th May 2018
Completion date 13th May 2022
Construction period 48 months excluding defects notification period
Amount ( of Liquidated Damage) 0.05% of the contract price per day in both currencies
Limit of Liquidated Damage 10% of Contract Price
Defects Liability period 12 months
Minimum Amount ( of Interim
ETB 5,000,000.00
Certificate
Amount ( of Performance Security Bank
10 % of Contract Price
Guarantee
Minimum Amount ( of Third Party ETB 2,000,000.00 per occurrence with a number of
Insurance currencies unlimited
Advance payment 20% of the Contract price in both currencies less VAT
Monthly amortization of advance 33.4% of the Amount ( of monthly Interim Payment

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Certificate
10% from each IPC, Maximum deduction 5% of the
Retention money
Contract amount

Typical cross-section of the road Type 1……., Type 2……, Type 3……Type 4…..

Elapsed time 33 month out of 48 (68) %


Work Executed to date 0..19%
Normal working hours 8 hrs.( 8:30 -12:30) & (13:30-17:30)
Local One percent above the central bank of Ethiopia
Calculation of financing charges
lending rate, foreign prevailing LUBOR rate plus 2%
Max. the total liability of Contractor to
The accepted Contract Price
Employer
Max. the deductible amount for insurance
ETB 50.000.00
of Employer risks
Date by which the BD be appointed 28 days after the Commencement date
The DB shall comprise of One sole member
Appointment (if not agreed) to be made The Chairman of the International Chamber of
by Commerce
International Arbitration Institution International Chamber of Commerce
Place of International Arbitration Paris France

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1.3.3 Organizational Chart for the Project Staffs

Ethiopian Roads
Authority
Employer
(client)

Professional Staff
NEWTECH Consulting Group in JV
with NET Consult

Supporting&Junior Staff

Resident Engineer Claims Expert


Mohammed Shalal Begashaw Debele

Secretary
A/Resident Engineer Administrative
Zehara Jemal
Samuel Tesfaye Support Staff

Quantity Structural Senior Pavement/


Highway Hydrologist Geotechnic Environme
Surveyor Eng Surveyor Material
Engineer Engeda al Engineer ntalist
Solomon Tegege Tesfay Eng
Mekari Z/Agegneh D.rMamou Getahun
Yosef Eshetu Alemu Resom
Z/Agegneh u n Eltayeb Worku
Getachew

Inspector
Prepared By: - Daniel Getachew
Draft OfPage 10
works
Person (2)
Moham Wondessen
med Birhanu &
Surveyors Material
Structural (2) Inspector (2)
Soil Laboratory
Inspector (2) Yohannes Zelalem Abera
Technicians (2)
Fitsum Sisay Yilma &
Wondmu Tebeje
mulugeta
Chapter Two Worknegn Endale
Alem
2.1 Overall Internship Experience
2.1.1 How I Get to the Company

First of all, to accomplish this I decided many things on my own and also by asking people
related to the field like which field is really I want is it High way? or is it
Structural(building)? And also where I should attend this intern program in Addis Ababa or
Outside Addis Ababa? And also which company plays a big role to increase my practical
skill and also my knowledge?

After all the decision I decided to visit Ethiopian Roads Authority(ERA), but they mentioned
that they have no project at the time in Addis Ababa and asked me if I was willing to move
and work outside Addis Ababa.

Finally, I decided to work outside Addis Ababa for so many reasons the first one is the
eagerness to know much in the field of High Way, second of all the project is an international
project so that's why and also my brother work there for the consultant side so there will be
freedom to know and ask, the last but not least when after graduation my career does not
always continue in Addis Ababa so I decided to face it the challenge.

After all, I received an acceptance paper from the main office of ERA and I started the
internship program at wolayita (SODO –DINKE PROJECT).

2.2 Work section I participated in The Company


In this difficult time, I try to cover and try to understand how it has done before I arrived here
and participate in all kind of area of the work like

2.2.2 Site work or Fieldwork


2.2.2 Office work
2.2.3 Practical or Laboratory test work

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2.2.1 Site work or Fieldwork

Under site work, there is much activity like

2.2.1.1 Feasibility studies & Site investigation


2.2.1.2 Surveying
2.2.1.3 Earth work & construction of pavement
2.2.1.4 Construction of structures
2.2.1.5 Site inspection, etc…..

Observation

The first thing in project is observation the project of the road alignment passes mostly
through flat and rolling terrain and on the final section in mountainous terrain. Sharp curves
with low visibility are encountered at some locations and areas of steep gradients are noted.
The project road at the sta. 17+400 diverges into 2 alignments a main alignment leading to
the Gesuba and a by-pass which join together at Sta. 32+729. The alignment passes through
other urban/peri-urban areas most notably Selam Ber at Sta 64+400. No standard road and
information signs are visible along the road except in the vicinity of 3 schools where children
crossing sign was observed. Another non-standard sign was seen however the placement did
not provide adequate warning to the motorists. Animals were seen to pass across the road.

Selection photo of the site visit are provided here in under

Fig 1. Start of road at Sta. 0+000 Fig 2. Alignment passing urban area to be
upgraded To dual carriageway Sta.0+000 and 1+500

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Fig 3. Area of proposed intersection at Sta. 1+500 Fig 4. sign along road warning of an
Location upcoming school

Fig 5. Gesuba By-pass shall require design of Fig 6. Animals crossing will require special
attention Intersection at Sta. 17+400&32+700

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Fig 8. Sign warning of sharp bend on
inadequate Fig 7. Steep grade and sharp bend on approach
To Location and non-standard type bridge

2.2.1.1 Site investigation

Before starting any work on the site the first thing is to investigate the site as i said before the
road project is upgrading so we have to identify which part of the road is going to be
demolished or need a new supplement or which part of the road keep as it is and which part
needs upgrading.

Fig 9. View of triple span bridge Fig 10. Deck slab holes on the superstructure

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For example, when we take this structure found at Km 43+050 this is an existing span 3*20m
reinforced concrete deck girder bridge supported on reinforced concrete abutment and piers.
The deck slab is found in poor condition with more than two(2) holes on the superstructure
while the substructure is found in sound structural condition with no sign of distress. The
bridge is located approach Dinke side is tight curve followed by a tangent section which
renders the bridge crossing unsafe at the higher travel speed. The hand-laid rock riprap on all
four sides is washed away exposing the roadway embankment for further erosion.

So like this analysis at the same procedure, the rest of the road part is studied in detail and put
the weakness and how it should be constructed

Overall of this site investigation has revealed the following defects that have occurred during
the service life of the structure;

o Substandard pipe sizes


o Pipe joint crack, crack on head wall and wing wall
o Siltation at some pipes and box culvert
o Vegetation overgrow at inlet and outlet
o Erosion problem mainly downstream of the structure and at the end of head wall

Fig 11. Existing pipe vegetation overgrow Fig 12. Existing pipe culvert half silted

Sub grade Soil Investigation and Testing


For this project sub grade soil investigation aimed to assess the actual condition of alignment
material which include soil extension survey, sampling and logging for detail soil and
material review of the project road. The purposes of the sub grade soil investigation along the
road corridor are:

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 To assess the depth and nature of the material along the route corridor;
 To determine the quality and property of the sub grade to be incorporated in the
pavement design,
 To indicate problematic sub grade soil sections along the stretch and suggest possible
remedial measure that would suit the pavement design.

Investigation taken for the project is:


 Physiographic
 Climatic condition of the project area
 Geological setting of the project area
 Investigation of Existing Pavement
 Subgrade investigation
 Construction materials investigation
 Environmental and Social Aspects
 Cost of the project

2.2.1.2. Surveying

Surveying also one of the important activities which determine the horizontal alignment,
vertical alignment and so many important measurement are taken and inserted to the software
which is called eagle-point after inserting the result the software will show up and get the
proper measurement which implemented on the field on the implementation the surveying
activity also play a big role to put precisely

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Fig 13. Surveying practice

In this project surveying plays a big role we used it for:-


i. How much the normal ground level and the existing road needs Clearing and
Grabbing
ii. Which part of the road section needs cut and fill
iii. To measure and cross check each layer of the road up to Asphalt concrete(AC)
iv. To measure and limit the road width in each road layers
v. To indicate and measure the road ditches
vi. To measure and to put correct alignment for the structure purpose like Box pipe and
also Bridge
vii. To check the elevation of the bridge and so many purposes’ etc……..

For one surveyor before starting the work he needs


 A request paper on which section of the road work is he start working
 Templates which show the cross section of the road or the drawing of a
structure
 Recording paper
 Equipment’s like level, total station and GPS
 Chain mans which holds a staff and make a mark on the road
 Peg to indicate how much cut/fill is needed

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In the project there is two surveyors one for contractor side another for consultant side. The
surveyor for contractor side is responsible to do all the activities as the project design require
for the road section and also for the structure section after finishing the activities as the
design the surveyors in consulting side asked by a request paper to check and approve so they
check the desired elevation of the road or the structure so if the actual elevation attained the
design one within the tolerable range the surveyor will approve the work if not they will
comment and reject the work to be reworked or to be corrected.

Surveying work I performed


Before starting and performing the outside work I take a few lesson in the office with the
surveyor engineering staff like how to read from a templates, how to set up a bench
mark(BM),and learn the method of reading leveling by height of instrument and rise & fall
method, and travers after that I started the field work.

Works that I have performed while I was working with the surveyor
 First setting out the total station instrument
 By using the total station plotting the left hand side of the road(LHS),center line of the
road(CL), and the right hand of the road
 Read using level instrument
 Recording data on the paper sheet and calculating it
While I performed this activity I understanding it easily because there is some knowledge I
gained from the university and after seeing it once the procedure are the same throughout the
end.

The challenge I have faced while I was working with the surveyor is lack of knowledge for
understanding the structure drawing and operating the total station to put the alignment where
the structure is going to be constructed.

I solved this kind of confusion and misunderstanding by asking and by practicing daily with
the surveyors.

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Fig 14. Recorded data to check how much Fig 15. Plotting RHS, CL, and LHS of the

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cut/fill needs road

2.1.1.3 Earth work & construction of pavement


Before earth work the preparation of Right-of-way (ROW) is important because it is the
initial operation in the construction of the road project. All the obstructions which were found
along the alignment of a road should be removed and disposed according to the specification
of design; such as trees, undergrowth of roots, abandoned utilities, and drainage structures. A
careful investigation should be made in order to determine the location of all underground
facilities within the right of way. Over all earth work includes excavation of material to attain
the design elevation of the road.

A. Clearing & Grubbing


Before proceeding to the clearing and grubbing setting out of work and protection of survey
monuments for this first the contractor surveyor and the consultant surveyor jointly done
assessments starting from the project beginning to end, the total length of 75 Km long the
main road and also the Gasuba by pass starting from 17+360–29+079.

According from the original designer used primary and secondary (GPS&BMS) Reference
points almost 80% were changed in case of near to offset distance for design center line,
damaged or disappeared.

The detail of reference point status is shown as tabulated below:

REFEREN No OF OLD No OF No OF No OF GOOD No OF NEW


CE REF.POINT DAMEGED DISAPPEARE CONDITION ESTABLISHE
REF.POINTS D REF.POINTS D
POINT
or NEAR TO REF.POINTS REF.POINTS
DESIGN
CENTER
LINE
GPS 48 08 36 04 44

BMS 266 80 158 28 238


Table 3.1 project Geometric control point status

After completing this setting we can start the clearing & grubbing work.

In general clearing shall consist of the removal of all trees, brush, and other vegetable all
other objectionable material including the disposal of all material resulting from clearing and
grubbing. It also includes the removal and disposal of structure that obtrudes, encroach up on

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or otherwise obstruct the work and which can be cleared by bulldozer. All stumps and roots
larger than75mm in diameter shall be removed to a depth of not less than 600mm below the
finished road level.

Except at borrow area the cavities resulting from grubbing shall be backfilled with approved
material and compacted to a density not less than the density of the surrounding ground

Fig 16. Clearing and Grabbing


B. Earthwork in Embankment and Sub-grade

The approved soils from roadway excavation/borrow areas shall be excavated and transported
to the site of embankment. The material shall be spread in layers of uniform thickness not
exceeding 200 mm compacted thickness over the entire width of embankment by mechanical
means and finished by motor grader. The selected sub grade 200mm below the bottom of sub
base shall have a maximum compacted layer thickness of 200mm.The moisture content shall
be checked and if found to be out of limits, the same shall be made good. If the moisture is
high, it shall be dried, by aeration and exposure to the sun, till the moisture content is brought
down to the required level. Compaction shall be suspended in inclement weather.

If the moisture content is less, water shall be sprinkled from a water tanker having sprinkler
attachment and mixed thoroughly in soil by blading, dishing or borrowing until uniform
moisture content is obtained.

Vibratory or other rollers shall be used for achieving the required results. Around structures,
compaction shall be done to achieve 95% of Modified

The surface of the embankment shall be maintained at such a cross slope as will shed water
and prevent ponding. Compaction tests shall be conducted to confirm the field dry density by
sand replacement method used to measure field moisture content.

The next layer shall be placed only after achieving the required test result and due approvals.

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Fig 17. Sub grade lay

Acceptance Criteria
Test Description Selected Sub
Ordinary Fill
Grade (Capping)
Liquid Limit (LL) <55% _
Plasticity Index (PI) <30% _
Compaction (% of Modified AASHTO >95% >95
Density)
Soaked CBR compacted at OMC >5% >15%
(Modified AASHTO at 95% of MDD)
CBR Swell at Modified AASHTO <2% <2%
Density
Table 3.2 Embankment material specification

Minimum acceptable density for any Test


Position of Layer – Material
(% of BS Heavy or Modified AASHTO MDD)
Ordinary Fill 95
Sand Fill 100
Selected Sub-grade 95
Table 3.3 Minimum acceptable density

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Dimension Position of Layer Tolerance Limit

Levels Sub grade layers +10mm and -40mm

Levels Selected sub grade layer (Capping) +10mm and -30mm


Width (from
Final fill layer and selected Sub-grade layer +200mm and +100mm
CL)
Table 3.4 construction tolerance
C. Capping layer

Capping layer is provided to support the sub grade. Before implementing the capping layer
first any weak point and defected part of the sub grade corrected to satisfy the density and
smoothness requirement as specification after that the dumped material is mixed and placed
using grader.

Shower trucks are used providing water to attain optimum moisture content of the material
when the moisture contain of soil is less than (OMC-2%) in this case additional water is done
by a water tanker (water spreading) but the moisture content of soil greater than (OMC+2%)
in this case the soil is skewed if required and left under the sun to get the moisture content
under the desired limit.

D. Sub base

Sub base is a pavement layer which is laid on top of sub grade or if capping layer is required
the sub base laid on the top of capping layer. The materials used for the construction of sub-
base layers shall be either:

1. Natural Gravel;
2. Scoria (Cinder Gravel);
3. Weathered Rock;
4. Crushed Gravel;
5. Crushed Rock or crushed Boulders;
Any other granular material complying with the requirements of this clause.
The sub base material is spread in layers to give a compacted thickness not exceeding 200mm
and not less than 100mm. The final compacted layer shall be free from concentrations of
coarse or fine materials. The compaction is completed as soon as possible after the material
has been spread. A vibratory roller is used for achieving the required results. The compaction
shall be done to achieve minimum mean density 97% of Modified AASHTO MDD. Around
structures, compaction shall be done by using small vibratory roller/plate vibrators.

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Fig 18. Sub base layer

Sieve size(mm) % passing by weight


50.0 100
37.5 -
25 55-85
9.5 40-70
4.75 30-60
2.0 20-51
0.425 10-30
0.075 5-15
Table 3.5 Grading Requirement for sub base material

The material for granular sub base material Type-B shall satisfy the requirements as specified
in Table as given below

Description Requirement

California Bearing Ratio(CBR) in accordance with 30% minimum


AASHTO T-193

Grading Modulus not less than 1.2

Plasticity Index shall not exceed 12%

Los Angeles abrasion value of not more than 51%

Minimum in-situ dry density not less than 97% minimum

Table 3.6 Type-B granular sub base material shall satisfy

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E. Base course

The underlying gravel sub-base layer shall be checked immediately before placing the
crushed stone base material for any damage or deficiency which shall be made good as
directed by the Engineer.

The approved Crushed stone material after mixing shall be transported from the approved
plant site and dumped in quantities sufficient to ensure that after construction the compacted
layer will comply with the requirements of layer thickness and levels as per approved cross
section.

The material spread in layers of uniform thickness not exceeding 200 mm compacted
thickness over the entire width finished by motor grader. Any excess crushed stone material
shall not be spread over the side fill, but shall be loaded and removed from the road.

The moisture content shall be checked and if found to be out of specified limits, the same
shall be made good. If the moisture is high, it shall be dried, by aeration and exposure to the
sun, till the moisture content is brought down to the required level. Compaction shall be
suspended in inclement weather. If the moisture content is less, water shall be sprinkled from
a water tanker having sprinkler attachment and mixed thoroughly by blading, dishing or
borrowing until uniform moisture content is obtained. The moisture content of each layer
shall be checked. It shall be in the range of 1% above or 2% below OMC.

The compaction shall be done as starting from the edge of pavement to center where road is
in normal camber and from the inner edge to the outer edge in case of super elevated sections
with sufficient overlapping. Vibratory or other rollers shall be used for achieving the required
results.

The finally compacted layer shall be free from surface laminations, portions exhibiting
segregation of the fine and coarse aggregate, corrugations or other defects. The finished
surface of the base course shall be maintained at such a cross fall as per the approved cross
section.

The tests conducted to confirm the field dry density by sand replacement method. Rapid
Moisture Meter shall be used to measure moisture content.

Before commencement of the actual construction of any base course, a trial section of not less
than 1000sqm shall be demonstrated so that the equipment and processes that are proposed to

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be used will enable to construct the base course in accordance with the specified
requirements. The trail section(s) shall be laid where indicated by the Engineer.

Only when such a trial section has been satisfactorily laid and approved by the Engineer, the
actual crushed stone base layer work shall commence

F. Bituminous Surfacing and Road Base

In this project the asphalt part of the road constructed very well because every activities done
by as the specification required for example when we see

(a) Aggregates for Surface Treatment

The aggregate shall consist of approved crushed stone complying with the requirements the
grading, flakiness index and hardness shall be as given in Table for each nominal size of
stone.

I. grading

Type Continuously –graded


Grading Limits for nominal size of aggregate 25mm
Sieve size(mm) Fraction passing by mass (%)
26.50 100
19.00 85-100
13.2 71-84
9.5 62-76
6.7 55-75
4.75 42-60
2.36 30-48
1.18 22-38
0.600 16-28
0.300 12-20
0.150 8-15
0.075 4-10

Nominal mix proportions by mass (%)


Binder Type 80/100Penetration

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Aggregate 93.5
Bitumen content 4.6-5.4
Active filler* 0.6-1.2
Total 100

Bitumen content (%) 4.6 – 5.4


Marshall Stability (KN) Min. 9.0 Table 3.7
Aggregate Flow (mm) 1.5 – 4 for Asphalt
Concrete Air Voids (%) 3.5 – 4.5 shall
conform Voids in Mineral Aggregate (%) 16 – 20
II. Voids Filled with Bitumen (%) 70 – 85 Hardness:
Filler/bitumen ratio (1) 1.2 – 1.8 When
tested in accordance with BS the aggregate crushing value shall not exceed 25.
III. Flakiness: The maximum flakiness index shall be as follows:

Nominal Size (mm) Maximum Flakiness Index %


Asphaltic Surfacing Aggregates
Grade 1 Grades 2
19.0 25 30
13.2 25 30
9.5 30 35
6.7 30 35

(b) Materials for Prime Coat and Bituminous Binders

I. The Prime Coat: material shall be MC-30 cutback bitumen complying with BS3690
and/or AASHTO M82.
II. Bituminous binder: for Asphalt Concrete shall be 80/100 Penetration Grade Bitumen
complying with the requirements of AASHTO M20-70:

The bitumen shall be homogeneous, free from water, and shall not foam when heated to
1750C (3470F). 80/100 Penetration Grade Bitumen shall conform to the requirements given in
Table 3.7

Test Minimum Maximum


Penetration at 250C (77 F) 100 g., 5 sec 80 100
Flash point, Cleveland Open Cup, °F 450 –
Ductility at 25 C (77F) 5 cm. per min., cm 100 –
Solubility in trichloroethylene percent 99 –
Thin-film oven test, 1/8 in. (3.2 mm), 163C (325 F) 5
– 1.0
hour Loss on heating, percent
Penetration, of residue, percent of original 50 –

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Test Minimum Maximum
Ductility of residue at 25C (77 F) 5 cm. per min., cm 75 –
Spot test (when and as specified (see Note 1) with):
Standard naphtha solvent Negative
Naphtha-xylene solvent, percent xylene Negative
Heptane –xylene solvent, percent xylene Negative
Table 3.7 Bitumen Binder for 80/100 Penetration Grade Bitumen

Note: (1) The use of the spot test is optional. When it is specified, the Engineer shall
indicate whether the standard naphtha solvent, the naphtha-xylene solvent, or the heptane-
xylene solvent will be used in determining compliance with the requirement, and also, in the
case of the xylene solvents, the percentage of xylene to be used.

G. Prime Coat

No longer than 24 hours before spraying, the layer to be primed shall be broomed and
cleaned of all loose or deleterious material by means of a rotary broom and hand brooms. A
light spray of water, sufficient to dampen the surface, shall be uniformly applied to the layer
immediately before the application of the prime. If the water is over applied the layer shall be
allowed to dry until a uniform damp surface is obtained.

Before any prime material is sprayed the layer to be primed shall be checked for compliance
with the surface and other requirements specified. Any sections not complying with the
specified requirements shall be corrected as specified.

Suitable approved material shall be used at all joints at the beginning and end of all sprays in
order to obtain a neat start and cut-off.

Maximum storage temperature


Material Spraying Temperature
C
range oC
Up to 24 hours Over 24 hours
Type of Prime
Cutback bitumen
MC-30 65 40 45 – 65

Table 3.8 The temperatures for storage and spraying shall be in accordance with
All prime materials stored in a heated condition stored in a container with a properly
functioning circulation system and having a securely fitting lid. No heat shall be added to
materials delivered above storage temperature until the temperatures are below those
specified above unless the materials are intended for immediate use.

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As soon as the primed surface has dried sufficiently to allow the traffic to pass over the road
without picking up or otherwise damaging the primed surface, the road shall, where
practicable, be opened to public traffic for a period of 3 days

H. Asphalt Concrete
The areas to be surfaced shall be cleaned of all dust, dirt, dung, oil, or any other foreign
materials that may be deleterious to the surfacing by air compressor.

The areas shall be checked for compliance with the surface tolerances and all other require-
ments specified. Any portions that do not meet these requirements shall first be either
corrected or removed and reconstructed, before they are surfaced.

The temperature ranges between which bituminous binders are to be heated shall be as given

Recommended
Maximum storage Heating and spraying
temperature,
Temperature, oC Temperature, oC
Materials o
C
Over 24 Up to 24
Minimum Maximum
hours hours
80/100 115 165 150 175 165

Table 3.10 Temperature ranges of bituminous


As soon as the aggregate has been applied, rolling shall commence with a self-propelled 15
tones pneumatic-tired roller working parallel to the center line of the road from the shoulders
towards the crown of the road until the whole surface has been covered at least three times
with the wheels of the roller initially

After the bituminous binder has set-up sufficiently to prevent any aggregate from being
dislodged, the surface shall be slowly dragged with a broom drag in order to ensure even
distribution of the aggregate. If there are areas, which are deficient in stone chips, additional
material shall be added by hand so as to leave the carpet with one layer of stone shoulder to
shoulder.

If there are areas having an excess of stone chips such excess shall be removed by hand so as
to leave the carpet with one layer of stone shoulder to shoulder. The importance of applying
only a single layer of stone is stressed. Every care shall be taken to avoid an over-application
of stone.

When the spreading of aggregate is completed, the surface shall be rolled with a 15 ton
pneumatic-tired roller for two to four coverage’s. Final rolling shall be done with a flat

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steel-tired roller of 6 to 8 tones mass, working parallel to the center line of the road from the
shoulders towards the crown of the road, until every portion of the area concerned has been
covered by two to four passes of the roller, provided only a minor amount of crushing of the
aggregate takes place. If general crushing occurs under the rollers, such rolling shall be
stopped regardless of the number of passes completed by the roller.

2.1.1.4 Construction of structures


In this project there are a lot of structural structures like pipes, culverts, ditches, and bridges
these different structural difference is based on the their purpose like of

- Protecting soil from erosion


- To make connection one to another
- Help to widened the road section
- To keep the natural flow of water as it is
In the project there are 7 bridges, 5 Box culverts and 2 slab culverts, and 139 pipe culverts.
The detail is in the following table.

Total
No.of Item
Remark length( Width(m) Location(s Name of
Spans NO
m) tation) structure
Concrete bridge 9 9 1 5+350 Bridge No.1 1
Ditto 20 20 1 30+500 Bridge No.2 2
Ditto 20 20 1 37+020 Bridge No.3 3
Ditto 60 20 3 43+050 Bridge No.4 4
Ditto 60 20 3 52+220 Bridge No.5 5
000+62
12 12 1 Bridge No.6 6

20 20 1 220+66 Bridge No.7 7


Different in size &
19 Box Culverts and 5 Slab Culverts 8
length
Different in size lenth Pipe culvert-in 139 locations 9
Culvert
When we say culvert it is a minor drainage which discharge collected water that come from
sloped catchment. And also three types of culvert implemented in this project

 Box culvert
 Pipe culvert
 Slab culvert
Box culvert

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When we say box culvert it is like small bridge having total length of 6M or less than 6M
between the face of abutment and also considering the catchment flow it may be constructed
with a single box, or multiple box cells placed side by side and it made of RCC. The upper
and the bottom slabs are cast monolithically.

Fig 19. Box culvert

Pipe culvert
Pipe culvert is most economical for small drainage crossings. It is constructed in a diameter
of less than 1.8 diameters

Pipe culvert is laid on either lean concrete when the foundation is black cotton soil (low
bearing capacity) or directly on the foundation soil when the does not show differential
settlement and swelling also if the discharge of water is more two pipe cells can be used. It is
surrounded by the masonry at the inlet and out let. This is done to preserve the pipe from
erosion.

Fig 20. Two cells pipe culvert

Slab culver

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Slab culvert is also the same with box culvert but the difference is the construction in slab
culvert
In the bottom no provided only the upper side (road way) and the side abutments
Bridge
Bridge is also a drainage structure which facilitates a communication route for carrying roads
across an obstruction with or without water. In this project the bridge is across an obstruction
with water from other structure bride contain some complex designing considering live load,
dead load, wind load, considering hydrological data.

When we see the sub structure of the project bridge the foundation starts below three meter
from the ground and also before the pad foundation construct the is one meter rock fill after
that there is two meter cyclopean which mean the construction of 60% rock and 40%
concrete to make bond between rocks

Fig 21. Bridge number three 20M span

2. Work tasks I have been executing


Site work I performed
While training for about four months in this site with the company they trained me both
office works and on site activities. And I try to visualize the undergoing activities on site like
Excavation work, Fill work, Sub grade layer construction, capping layer construction, Sub
base layer construction, Base course layer construction, Prime coat, and Casting Of concrete

In the office I try to grasp different kinds of office works especially how to organize daily

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Executed data’s from site and try to write the weekly report as well as the monthly report and
also some new knowledge on Eagle point software work. I try to complete my task within a
specified time accurately and neatly. I try to work the task independently that will help me to
understand the problem and try to work it independently.

Since performing such kinds of tasks connects you with other members of the company I
make a smooth relationship with all of the office, as well as the site workers.

Surveying work I performed

In surveying the main task is setting out design works to the ground. Instruments used for
setting out works include total station, GPS, and leveling. I have been with the survey and
work and in those days I have tried to cover all survey works.

Works that I have executed while I was working with the surveying crew are operating the
total station instrument; this instrument is helpful in setting out of Centerlines, slope stack
limits, and excavation limits. While this section I have performed good, this is because I have
already got a good Understanding of survey works in the university and almost the same
procedure is used in the Practical world.

The challenge I have faced while I was working with the surveyor the surveyors have no
enough time for me because they have to cover all the daily work and the other challenge is
most of the work executed is far from where I am so lack of transportation also one of the
challenge.

Inspection work I performed

In inspection always there is an inspection work in different section there is material


inspector, survey inspector, work inspector. From all this inspectors I have a chance to
perform and see how to inspect and how to approve and reject the work.

For example with the survey inspector to check the asbuilt by using leveling check the actual
elevation with the design elevation if it ok the work approved but when there is a gap
between the actual elevation and the design the engineer ask to be worked again from this
proses I perform reading the leveling and cross check it.

In general Road construction is not fixed at a specific place and time. Every task is carried
out at different station. It needs movement from one station to the other station. To do this,

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transport is necessary but the cars are limited in number. So I have faced such a challenge to
do a work in the construction site.

When there is no task I try to go to the site and observe the practical view and try to ask
questions and collect data. Also I ask the quantity surveyor office by which I try to learn
some software’s like Auto CAD and Eagle point.

CHAPTER THREE
III.1 Benefit of the internship
The internship program is very essential for students. The student who works in the
internship can get much more benefits. This benefit is in two ways the first one is in
theoretical knowledge the other is by practical practice knowledge. I have gained many
benefits from the internship program. The benefits that I gained are:

 Organizing
 Work ethic
 Coordinating
 Leadership skill
 Team work
 Upgrading knowledge
 Development of guiding life

Organizing
When I say organizing responsibilities of each man power either skilled or unskilled have to
be defined. This also helps you to test the manpower performance and handle the work but
this organizational skill comes with in experience.

Work ethics

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When I say work ethics I have learned what work ethics is and how it is applied in the
internship program. Work ethics is very essential to run every work effectively and as a
professional work ethics also play a big role for the project progress. I learned the following
work ethics which every employee should respect.

 Punctuality
 Reliability
 Accountability
 Loyalty and
 Responsibility

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Leadership skill
I gained sufficient leader ship skill in the internship program. Each task of road construction
needs a leader. I learned here that how to lead one task because is very important. I
understood that how to solve disputes which are occurred on work

Team work and communication

Road construction needs a team work and good communication. It needs communication of
the team members. The contractor and consultant streams communicate each other in order to
run their activities effectively. But, the project will not attain the required standard if there is
no communication within the team and the project is not completed within the specified
time. So I understand that interpersonal communication is very necessary to run the project
work effectively.

Upgrading knowledge

When I say upgrading of knowledge I obtain different manuals such as AASHTO, ASTM,
ERA, Tanzania Manual and Kenya manual. These manuals have their own material quality
specification, method test, method of construction specification, structural analysis, and
traffic design specification. So I get such a theoretical knowledge. I also develop the mix
design knowledge and I know the parameters which should be satisfied when mix design is
done.

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CHAPTER FOUR
4.1 Recommendation and conclusion

4.1.1 Recommendation
My recommendation for the company and for the university.
For company
 There should be traffic sign post on the road to Gide the road because when at the
night time you can’t see anything if there is a curve in front of you and also there is
also some restricted place they just dump the material there so there should be a
traffic sign post which can reflect at night time
 When the base course is finished the motorist inter in that area and ride on it that
means they make small segregate on the road so when the base course is finished they
should assign traffic police to keep the road safe
 Regarding health and safety regulations all the construction company’s should strictly
implement the rules to wear helmets, providing safety shoes
 It better for the company to have and use machineries and modern working equipment
to run its projects on schedule and to made possible speedy, accurate and less cost
work.
 The other one is on the specification it say when one layer is finished and proceed to
the other layer the finished layer have to be checked if there is some uncertainty is
happening but in this project the first finished layer is not secondly checked just
continued it may cause a deformation
 There is lack of vehicle for inspector engineers that also affect the work because many
times the inspectors approved the work that they doesn’t see
 I saw some carelessness on traffic count day the people that assigned to count
sometimes they are not there for more than 2 hours that means there will be error data
 From the good side this internship program gives as a lot of opportunity to me and to
the other students also by increasing our knowledge by experiencing the real world
work this kind of student training program must continue

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4.1.2 Conclusion
In general the road construction work is an interesting one and also some bad effect in life in
a good sign you can share so idea in one project and gain some thing and also in road
construction you have to update yourself every day because sometimes the working method
changes or upgraded the bad thing is you always work outside your family the work make
separate with the family.

Like I said in the recommendation part this internship program must continue strongly in
organized manners because this program try to summarize all the four years we cover during
that time

I have gained different kinds of knowledge which professions participate in road


construction. Road construction is not a specific work. It needs the integration of different
professions. Geological profession, environmental engineer, hydrological profession, high
way engineer, structural engineer, material engineer, local persons are participating in road
construction. This shows that road construction is the output of different bodies.

I have learned that road construction needs high financial strength. Investment on road
construction needs very high capital. Road construction needs a lot of machine to be run. The
machines are also very huge and their cost is counted in millions. A number of professions
are participated. It also needs a large number of labors. The construction materials of road
construction have high cost and even sometimes the materials are not available near to the
project. So road construction needs financial strength to resist the challenge of different type
of costs

Some works are time consuming and others are done fastly when you work in rock part of the
road to get the design elevation you may need drill machine or small bombs for blasting and
so many knew knowledge that didn’t seem easy.

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REFERENCE
1. ERA specification manual
2. AASHTO manual
3. Design manual of the project
4. ASTM manual
5. Internet-based
6. From the text book

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