REMEDIAL MEASURES AGAINST FLOODING IN AL

JOUF

METHOD STATEMENT
ALOMAIER TRADING & CONTRACTING

Riprap works

Method Statement No. 02

Issued by:

Rev. No. Date Description Prepared Approved

Checked

0 Riprap CM QCM PM

Riprap Method Statement REMEDIAL MEASURES AGAINST FLOODING IN AL JOUF

 TABLE OF CONTENTS

1 Introduction

2 Site staff

3 Working hours

4 Site emergency procedures

5 Site establishment

6 Scope of work

7 Material

8 Riprap stockpiles

9 Plant & Equipment

10 Execution

11 Safety

12 QC/QA

Riprap Method Statement REMEDIAL MEASURES AGAINST FLOODING IN AL JOUF

 1- Introduction:
Riprap works:

 Rock riprap protects soil from erosion due to concentrated runoff. It is used to
stabilize slopes that are unstable due to seepage. It is also used to slow the
velocity of concentrated runoff which in turn increases the potential for infiltration

 Inlets and outlets for culverts, bridges, slope drains, grade stabilization structures,
and storm drains; where the velocity of flow from these structures exceeds the
capacity of the downstream area to resist erosion.

 Riprap offers an easy-to-use method for decreasing water velocity and protecting
slopes from erosion. It is simple to install and maintain.

 Riprap provides some water quality benefits by increasing roughness and

decreasing the velocity of the flow, inducing settling.

2- Site staff :

 The appointed Riprap of Al-Omaier staff will ensure the following resources to
carry out the works as required on site:

 Demolition Site Manager

 Demolition Site Supervisor
 Equipment Operators
 Subcontractor staff
 Safety representative

3- WORKING HOURS
06:30 am - 17.00pm Saturday-Thursday
No working hours on Friday
Any work with overtime will be notified before starting work

Riprap Method Statement REMEDIAL MEASURES AGAINST FLOODING IN AL JOUF

 4- Site emergency PROCEDURES:

ALQuriat Police Station is 13 Kilometers away at Khalid ibn Elwalied street (Tel: 999),
ALQURIAT Fire and Rescue Station is 18 kilometers away in the Elrifaa region (Tel: 014
642 2996), The nearest Hospital with Accident and Emergency is 17 kilometers away in Ibn
Sina street (Tel:014 642 4716).

Fig: Route to nearest Accident & Emergency

In the case of an emergency the following procedure shall be employed:

• The person who discovers the emergency shall call 999

• Inform which emergency services are required

• Wait until the location has been confirmed before ending the call

• Alomaier staff shall direct the emergency service to the scene of the incident

• Alomaier will send an representative to assist with directing any emergency

vehicles

• In the case of Fire site operatives to report to Muster Point at the front gates

Riprap Method Statement REMEDIAL MEASURES AGAINST FLOODING IN AL JOUF

 SITE EMERGENCY PROCEDURES (continued) :

- Alomaier will provide trained first aiders with a first aid kit located in the site office.
- The Client will be notified as soon as possible after the incident. It is a requirement of the
(current) Reporting of Injuries, Diseases and Dangerous Occurrence Regulations that
certain type of Injuries, dangerous occurrences and diseases are reported to the Health
and Safety Executive.
- Reportable specified injuries, disease and dangerous occurrences will be reported to the
local HSE office within the time frames specified under the current regulations by the
Group HSE Manager using the appropriate online form.
- Records of all accidents will be kept for at least 3 years. All Lost Time Accidents (LTAs)

5- Site establishment:

1.1 The building will be situated within a secure site boundary made up of plastic barriers.

1.2 Warning signs (as described below) will be displayed at the appropriatepoints around the
perimeter of the site:
 Working Area
 Personal Protective Equipment requirements

1.3 All visitors to our site will be asked to sign in within the site office. They will be inducted into
the activities being carried out that day and at all timeswhilst they are on site they will wear
the required PPE and they will alsobe escorted by a member of safety staff.

Riprap Method Statement REMEDIAL MEASURES AGAINST FLOODING IN AL JOUF

 6- Scope of work:
 The work consists of furnishing, transporting, and the installation of grouted rock riprap
revetments and blankets, including filter or bedding where specified.
 Riprap works due to scope of Al-Omaier divided to constricting new Grouted Riprap and
rehabilitation old Riprap .
 New Grouted Riprap in the following stations:
(1244+241/1244+320/1244+431/1243+915/1119+261/1120+110/1142+921/1206+575/1
210+275/1209+950/1213+125/ 1244+615/1208+825)
 Riprap Rehabilitation will be in the following stations:
(1208+525/1100+387/ 1209+100)

Photos from site:

Station (1244+241)

Station (1244+320)
Riprap Method Statement REMEDIAL MEASURES AGAINST FLOODING IN AL JOUF
7- Material
Rock riprap:
shall be dense, sound and free from cracks, seams and other defects conducive to accelerated
weathering. The rock shall be angular to sub-rounded in shape with the greatest dimension not
greater than 2 times the least dimension. It shall be free from dirt, clay, sand, rockfines, and
other material not meeting the required gradation limits.

The minimum apparent specific gravity shall be two and five tenths (2.5) and the maximum
absorption shall be six (6) percent when tested in accordance with MRDTM 304. The stone shall
not have an abrasion loss greater than forty-five (45) percent when tested in accordance with
MRDTM 309. The weight of Stone for the Various Classes of Riprap Shall be as shown in The
weight of Stone for the Various Classes of Riprap Size of Stone for "Loose Stone Riprap" shall
be quarried, fractured, or otherwise predominantly angular. Stone for other riprap and gabions
may be rounded (boulders) or angular.

Size of stone (kilograms) Percent of the Total Weight

Class A Class B Class C Class D Smaller than Size Shown
50 200 1000 5000 95-100
20 100 500 2000 50-100
5 20 100 500 0-50
1 5 20 100 0-10

Before rock is delivered from its source, the contractor shall designate the source from which
rock material will be obtained and provide information satisfactory to the engineer that the
material meets design requirements. The contractor shall provide the engineer technical
representative free access to the source for the purpose of obtaining samples for testing. The size
and grading of the rock shall be as specified in the construction drawings.

Portland cement
shall be Type II or Type III as specified in ASTM C 150 or as otherwise specified on the
construction drawings.
percent based on absolute volume, may be substituted for an equivalent amount of Portland
cement in the grout mixture.

Aggregates
shall conform to the requirements of ASTM C 33 for fine and coarse aggregate forconcrete, or
as shown on the construction drawings.

Water
shall be clean and free from injurious amounts of oils, acid, alkali, organic matter, or other
deleterious substances.

Air-entraining admixtures
shall conform to the requirements of ASTM C 260. If air-entrainingcement is use, any additional
air-entraining admixture shall be of the same type as that in the cement.

Riprap Method Statement REMEDIAL MEASURES AGAINST FLOODING IN AL JOUF

 8- Riprap Stockpiling
Stockpiling of riprap is an important part of a strategy for repairs of eroding unprotected banks
or revetments. Riprap should be sized for the “worst” conditions that might occur on streams in
the region. It may be worthwhile to stockpile very large, uniformly-graded rock separately, as it
is often required for toe construction during emergency works.

Specifications for stockpiled well-graded riprap should provide larger sizes than strictly required
based on expected velocities and depths, to account for segregation and breakage during
stockpiling and transportation.

9- Plant & Equipments:

Excavator CAT (Bucket fitted).
Shovel CAT.
Trucks.
Small grout mixer
Plate compactor
Water tank
Electrical and pneumatic grinders.
Relevant scaffoldings with platforms and hand tools.

Riprap Method Statement REMEDIAL MEASURES AGAINST FLOODING IN AL JOUF

 10- Execution:

A- Subgrade preparation:

The subgrade surface on which the rock riprap, filter, bedding, or geotextile is to be placed shall
be cut or filled and graded to the lines and grades shown on the drawings. When fill to subgrade
lines is required, it shall consist of approved material and shall be compacted to a density equal to
the adjacent existing soil material.

Filter, bedding, or geotextile shall not be placed until the foundation preparation is completed
and the subgrade surface has been inspected and approved by the engineer.

B- Bedding

The bed upon which the riprap or slope protection is to be placed shall be excavated to the
required grades and lines as shown on the plans or as directed and approved by the Engineer.
A footing trench shall be excavated along the toe of the slope as shown on the plans or as
directed by the Engineer. All footing trenches and excavations shall be approved by the
Engineer prior to placement of stones or concrete. Subgrade or base should be firm or
compacted as approved by the Engineer. Stones shall be placed so as to provide a minimum
number of voids; larger stones shall be placed in the footing trench and on the outside surface
of the slope.

C- Placement of rock riprap

Method 1 Equipment-placed rock—The rock riprap shall be placed by equipment on the surface
and to the depth specified. It shall be installed to the full course thickness in one operation and in
such a manner as to avoid serious displacement of the underlying material. The rock for riprap
shall be delivered and placed in a manner that ensures the riprap in place is reasonably
homogeneous with the larger rocks uniformly distributed and firmly in contact one to another
with the smaller rocks and spalls filling the voids between the larger rocks.

Rock riprap shall be placed in a manner to prevent damage to structures. Hand placing is required
as necessary to prevent damage to any new and existing structures.

Method 2 Hand-placed rock—The rock riprap shall be placed by hand on the surface and to the
depth specified. It shall be securely bedded with the larger rocks firmly in contact one to another
without bridging. Spaces between the larger rocks shall be filled with smaller rocks and spalls.
Smaller rocks shall not be grouped as a substitute for larger rock.

D- Placing Mixture

The grout mix shall be delivered to the site and placed within 1.5 hours after the introduction of
the cement to the aggregates. In hot weather or under conditions contributing to accelerate
stiffening of the concrete, the time between the introduction of the cement to the aggregates and
complete discharge of the grout batch shall be a maximum of 45 minutes. The engineer may
allow a longer time provided the setting time of the grout is increased a corresponding amount by
Riprap Method Statement REMEDIAL MEASURES AGAINST FLOODING IN AL JOUF
 the addition of an approved set-retarding admixture. In any case concrete shall be conveyed from
the mixer to the final placement as rapidly as practicable by methods that prevent segregation of
the aggregates, loss of mortar, displacement of the rock riprap, or a combination of these.

The grout mix shall not be placed until the rock riprap has been inspected and approved by
the engineer for the placement of grout.

Rock to be grouted shall be kept moist for a minimum of 2 hours before grouting.

The rock riprap shall be flushed with water before placing the grout to remove the fines from
the rock surfaces. The rock shall be kept moist before the grouting and without placing in
standing orflowing water. Grout placed on inverts or other nearly level areas may be placed in
one operation.On slopes, the grout shall be placed in two nearly equal applications consisting of
successive lateral strips about 40 m in width starting at the toe of the slope and progressing
upward.

The grout shall be delivered to the place of final deposit by approved methods and discharged
directly on the surface of the rock. A metal or wood splash plate is used to prevent displacement
of the rock directly under the grout discharge. The flow of grout shall be directed with brooms,
spades, or baffles to prevent grout from flowing excessively along the same path and to assure
that all intermittent spaces are filled. Sufficient barring shall be conducted to loosen tight pockets
of rock and otherwise aid in the penetration of grout to ensure the grout fully penetrates the total
thickness of the rock blanket. All brooming on slopes shall be uphill. After the grout has
stiffened, the entire surface shall be rebroomed to eliminate runs and to fill voids caused by
sloughing. The surface finish, following the completion of grout installation, shall consist of one-
third of the rock extended above the level of grout. The exposed rock will not have a plastered
appearance.

After completion of any strip or panel, no individual(s) or equipment shall be permitted on the
grouted surface for 24 hours. The grouted surface shall be protected from injurious action by the
sun, rain, flowing water, mechanical injury, or other potential damaging activity.

E- Curing and protection

The completed finished surface shall be prevented from drying for a minimum curing period of 7
days following placement. Exposed surfaces shall be maintained in a moist condition continuously
for the 7-day curing period or until curing compound has been applied as specified in this section.
Moisture shall be maintained by sprinkling, flooding, or fog spraying or by covering with
continuously moistened canvas, cloth mats, straw, sand, or other approved material. Water or moist
covering shall be used to protect the grout during the curing process without causing damage to the
grout surface by erosion or other mechanisms that may cause physical damage.

Riprap Method Statement REMEDIAL MEASURES AGAINST FLOODING IN AL JOUF

 The grouted rock may be coated with an approved curing compound as an alternative method to
maintaining a continuous moisture condition during the curing period. The compound shall be
sprayed on the moist grout surface as soon as free water has disappeared and all surface finishing
has been completed. The compound shall be applied at a minimum uniform rate of 1 litre per 5
square meter of surface and shall form a continuous adherent membrane over the entire surface.
Curing compound shall not be applied to surfaces requiring bond to subsequently placed grout
and/or concrete. If the membrane is damaged during the curing period, the damaged area shall be
resprayed at the rate of application specified for the original treatment.

Grout mix shall not be placed when the daily minimum temperature is less than 5 degrees celsius
unless facilities are provided to ensure that the temperature of the material is maintained at a
minimum temperature of 10 degrees celsius and not more than 40 degrees celsius during placement
and the curing period. Grout mix shall not be placed on a frozen surface. When freezing conditions
prevail, rock to be grouted must be covered and heated to within a range of 10 to 40 degrees celsius
for a minimum of 24 hours before placing grouting material.

Riprap Method Statement REMEDIAL MEASURES AGAINST FLOODING IN AL JOUF

 11 - Safety:

1.4 All necessary registers, accident books, diary, time book, test certificates,method statement,
risk assessment, health and safety plan etc will bekept on site under the control of the Site
Supervisor and can be inspected at any time. All accidents are to be reported to and
enteredin the site accident book.

1.5 A supply of spare hard hats, overalls, gloves, masks, weldersgloves, face visors (when
burning equipment is used) etc will be storedon Site.

1.6 At all times the appointed demolition contractor will ensure a high standard of Health and
Safety is carried out at all times on site.

1.7 All operatives on site must wear full PPE in accordance with HSE requirements including
safety boots, hard hats.
1.8 ‘No smoking on site’ policy will be adhered to at all times.

1.9 Adequate segregation of pedestrians and vehicular traffic will bemaintaine

12- QC/QA:
Approved quality plan for the project will fulfill the process respecting ITP for all execution stages
under Al-Omaier quality staff supervision.

Riprap Method Statement REMEDIAL MEASURES AGAINST FLOODING IN AL JOUF