Tuyên bố phương pháp này cung cấp thông tin chi tiết về quy trình, nhân lực, thiết bị, vật liệu và các tài liệu liên quan liên quan đến việc thực hiện công việc bảo vệ mái dốc bằng vữa Riprap theo các Thông số kỹ thuật chung, đặc biệt và bổ sung. Mục đích của Tuyên bố phương pháp này là cung cấp thông tin và đóng vai trò là hướng dẫn để thực hiện công việc đúng cách tại công trường nhằm tránh sự chậm trễ và đạt được chất lượng và an toàn tối đa
GENERAL DESCRIPTION
Project Information
The Cambodia Road Connectivity Improvement Project (CRCIP) is being implemented by the Ministry of Rural Development (MRD) in Cambodia with funding from the World Bank (WB). The project aims to support the improvement of climate resilient road accessibility in three (3) provinces, namely: (i) Kampong Cham, (ii) Tboung Khmum, and (iii) Kratie.
The RCIP which includes a total of 27 roads with a total length of 277.3 km is located in three provinces of Cambodia, namely: (i) Kampong Cham, (ii) Tboung Khmum, and (iii) Kratie Of which, 7 roads with a total length of 75.3 km are located in Kampong Cham province, 6 roads with a total length is 67.6 km is located in Tboung Khmum province, and 14 roads with a total length of 134.4 km are situated in Kratie province.
RCIP is divided into 3 civil work package by provinces and CW1 covering Kratie province subdivided into 2 lots: CW1-Lot 1 (72.9Km) and CW1-Lot 2 (61.5 Km)
In there, CW1-Lot 2 include 6 roads: KRT-1 (11.1 Km), KRT-2 (8.2 Km), KRT-3 (11.9 Km), KRT-6 (14.2 Km), KRT-20 (8.1 Km) and KRT-29 (8.0 Km) CW1-Lot 2 location is shown as Figure 1.1-1
Figure 1.1-1 Location of Contract Package on CW1-Lot 2
Project Objective
The Cambodia Road Connectivity Improvement Project (RCIP) will support the improvement of climate resilient road accessibility in targeted provinces The Royal Government of Cambodia(RGC) has requested the World Bank (WB) provide an Investment Project Financing (IPF).Targeted provinces under the proposed investment include Kampong Cham, Kratie, and Tboung
Khmum with a total population of over 2.3 million people The design of the proposed project builds on a network connectivity approach to improve road accessibility in rural areas, between rural areas and urban centers, and to the main network The project provinces were selected considering several criteria including density of rural population, agricultural potential, vulnerability to floods, condition of roads, and connectivity of provincial road networks to cover larger geographic area.
Road works will help to improve climate resilience and safety of road infrastructure The scope of works will include paving/sealing of the roads with climate adaptation and resilience measures and improving bridges and other road structure to climate-resilient standards The technical design will ensure that the identified climate-resilient measures reduce transportation costs and flooding risks and achieve the target of creating durable access to the main road network, markets, and services for the rural population.
INTRODUCTION
Reference Construction Specification
Description
This work shall consist of the provision and installation of riprap for stream banks, embankment slopes, cut slopes, bridge abutment slopes and other surfaces composed of erodible materials where protection is desired as shown on the drawings Generally, the protection will form an impervious layer constructed in or on designated surfaces and shall have at its bottom and ends anti-scour devices such as cutoff walls, toe walls or sheeting.
Slope protection shall also include impervious linings of concrete or stone riprap for ditches or gutters for the conveyance of surface runoff The linings shall be placed in ditches, gutters, chutes, outlets or other locations as shown on the Drawings, directed by the Engineer or as specified in General Specifications A filter blanket will be provided where it anticipated that there may be migration of fines through the riprap
Slope Protection by Grouted Riprap 6.2 General Specification
If directed by the Engineer, the various types of slope protection shall be constructed in the locations so directed, whether or not shown at those locations on the drawings, in accordance with the Standard Drawings.
Below is a typical of Grouted Riprap Slope Protection
SCOPE OF WORK
Description
The scope of work covers the following activities such as
+ Preparation works (Manpower, Equipment, Materials etc.);
+ Setting of Traffic Safety Devices;
+ Grouted Riprap Works include: Transport materials, excavation works, mortar mixing, build riprap stone works…etc.
Table List of Grouted Riprap Slope Protection under Project Scope
No From PK To PK Length (m) LHS/RHS Road No Remarks
6 Box Culvert 3+012 BS KRT-20 BC1-3+012
7 Box Culvert 0+077 BS KRT-29 BC1-0+077
Table 3.2-1: Table list of Grouted Riprap Slope Protection under Project Scope
Work Quantities
The following tables are the estimated quantities of Grouted Riprap, Class A from the Bill Quantities of the main Contract intended for references only and not for measurement purposes. Quantity might change in actual site condition.
Description Items No Unit Quantities
ORGANIZATION CHART
Organization Chart is as follow:
MANPOWER AND EQUIPMENT
Equipment
Table of Main Equipment serving for the construction:
No Equipment Capacity Unit Qty Remarks
2 Dump Truck 15T each 2 Hauling of Materials
3 Tamping Rammer 3T each 2 Compaction Works
4 Mortar Mixer 1.5 m 3 each 1 Mortar Supplier
5 Survey Instruments Set 1 Serving survey works
6 Minor Tools Gloves, hammer, shovel, bucket…etc.
* Note: This equipment will be increased according to the site requirements
Manpower
Manpower to be mobilized for construction work as below:
8 Safety Worker Person 2 Depend on site condition
* Notes: This manpower will be increased according to the site requirements
MATERIALS REQUIREMENT
List Table of Materials used for construction of Riprap Slope Protection Works
4 Riprap Stone Class A Used for Grouted Riprap Work
5 PVC Type PVC ỉ70mm Used for weep hole
6 Filter Material Used for weep hole
7 Geotextile Separation, filtration, reinforcement, protection, and drainage
Mortar
The mortar shall consist of one part of Portland cement and three parts of sand by dry loose volume with one fifth (1/5) part of hydrated lime and sufficient water to produce a mortar that is plastic and can be easily handled and troweled Re-tempering of mortar that has not been used for periods of 45 minutes or longer will not be permitted and such mortar shall be rejected.
Cement, Water, Sand
Cement, Water and Sand for mortar shall conform to the requirement of Section 5.1 of GeneralSpecifications.
Riprap Stone
Stone for riprap shall consist of field stone or rough, un-hewn quarry stone as nearly rectangular as practicable The stone shall be sound, tough, durable, dense, resistant to the action of air and water and suitable in all other respects for the purpose intended The stone shall have percentage of wear of not more than 50% as determined by AASHTO test method T 96 after testing stone which has been broken up in small pieces in conformance with T 96 requirements Riprap stones shall, in general, be of the wide flat type with their larger faces roughly rectangular and parallel. The minimum thickness of stone shall be 150 mm (measured perpendicular to face of riprap) No face dimension shall be less that the thickness of the stone.
Stones for riprap shall be Class A: Stones ranging in weight from a minimum of fifteen (15) Kg to a maximum of twenty-five (25) Kg, with at least 50 percent by weight of the stones weighing more than twenty (20) Kg.
Filter Material
As design drawing, Filter material used for weep hole shall be 0.06m3 of 20mm Gravel bagged in Polyester non-woven filter cloth.
Gravel material required for embankment slope protection as specified in Section 5.8 of General Specifications, or as approved by the Engineer and conform to one of the following grading requirements:
Percentage by weight passing square mesh sieves (AASHTO T27)
Table 6.5-1: Percentage by weight passing square mesh sieves of Gravel
Geotextile Material
Geotextile materials are typically made from synthetic polymers like polypropylene or polyester and can be woven or non-woven These materials provide functions such as separation, filtration, drainage, and stabilization, erosion control.
As design drawing, Geotextile material shall be Polyester non-woven type in accordance with AASHTO M288
The Contractor shall submit documentation relating to this material and obtain approval from theConsultant prior to its use on the Works.
TESTING AND SAMPLING
Lab
The contractor will submit to the consultant a qualified testing unit The profile will be submitted separately by the contractor The experimental unit will serve the project with the approval of the consultant.
Testing Standards
Unless otherwise specified, all tests shall be performed in accordance with the methods used byAASHTO/ASTM and shall be made by the Engineer or his designated representative.
Sampling and Testing Frequency
Table 7.3-1: Sampling and Testing Frequency for Mortar works
No Stage/ Activity Inspection required Reference Method Frequency
1.1 Approval of Mix Mix designing
Gradation AASHTO M-6 2 per Stockpile plus 1 per 800 cu-m Unit Wt AASHTO T-19 1 per Source plus 1 per 800 cu-m Specific Gravity AASHTO T-84 2 per Source plus 1 per 800 cu-m Absorption AASHTO T-84 1 per Source plus 1 per 800 cu-m Organic Impurities AASHTO T-21 1 per Source plus 1 per 800 cu-m Soundness AASHTO-104 1 per Source plus 1 per 800 cu-m
Deleterious Substance AASHTO M-6 1 per Source plus 1 per 800 cu-m
Petrographic - 1 per Source plus 1 per 800 cu-m
Setting Time AASHTOT131 1 per Lot or 1000 bags
Mortar Strength AASHTOT132 1 per Lot or 1000 bags
Yield Test for Cement Content AASHTOT121 1 per Lot or 1000 bags
Water Chemical Test AASHTO T-26 1 per source
Production Properties of mix Every Batch
Table 7.3-2: Sampling and Testing Frequency for Riprap Stone
No Stage/ Activity Inspection required Reference Method Frequency
Gradation AASHTO T-27 3 per Source plus 1 per 1,000 cu.m Abrasion AASHTO T-96 3 per Source plus 1 per 500 cu.m
Fractured faces Visual 3 per Source plus as required based on visual observation
2.1 Length, width & height of work Line & level As per the drawings Per area2.2 Formation level Finish level As per the drawings Per area
Experimental Work
- Contractor will provide full test certificates, origin of all supplier's materials.
- The material criteria shall conform to the requirements in Sub-Clause 6 “Materials Requirement” of this Method Statement and the requirements of Project General Specification.
- All tests shall be conducted in a manner approved by the engineer and shall be conducted in the contractor's laboratory.
Mortar testing is essential for evaluating the performance and suitability of mortar used in construction Mortar is a mixture of cement, sand, and water, and it serves as a binding agent in masonry applications, such as bricklaying and stonework Testing ensures that the mortar meets the required standards for strength, durability, and workability Below are some common tests and methods used to assess mortar (Some necessary criteria will be tested or as per engineer's instructions):
Purpose: To determine the ability of the mortar to withstand axial loads.
Method: Mortar samples are prepared in standard molds and cured for a specified period (usually
28 days) They are then subjected to a compressive load until failure, and the maximum load is recorded The compressive strength is calculated as the load divided by the cross-sectional area.
Purpose: To evaluate the ability of the mortar to retain water, which affects workability and adhesion.
Method: A specified amount of mortar is placed in a container with a porous base The amount of water absorbed by the mortar over a specific time is measured.
Purpose: To determine the time it takes for the mortar to start and finish setting.
Method: The Vicat apparatus is often used, where a needle is used to penetrate the mortar The time is recorded when the needle no longer penetrates the mortar to a specified depth.
Purpose: To assess the adhesion of the mortar to the masonry units.
Method: A sample of mortar is applied between two masonry units, and a tensile load is applied until the bond fails The bond strength is calculated based on the load at failure and the area of the bond.
Purpose: To measure the volume change of mortar as it dries, which can lead to cracking.
Method: Mortar samples are prepared and cured, and their dimensions are measured at various intervals to determine the shrinkage over time.
Purpose: To determine the amount of entrained air in the mortar, which can affect workability and durability.
Method: The air content can be measured using a pressure meter or other methods designed for this purpose.
On-Site Riprap Stone Testing Methods
Purpose: To assess the overall quality of the riprap material.
Procedure: Inspect the stones for cracks, weathering, or other defects Ensure that the stones are free from organic material, loose particles, and other contaminants.
Purpose: To verify that the riprap stones meet the specified size requirements.
Procedure: Use a set of sieves to classify the stones based on size Measure a representative sample of stones and ensure that the gradation conforms to project specifications (often specified in terms of the percentage of stones within certain size ranges).
Purpose: To ensure that the stones are of adequate weight to resist displacement by water.
Procedure: Use a scale to weigh a sample of stones Confirm that the average weight of the stones meets the project requirements.
Purpose: To assess the resistance of the stones to weathering and erosion.
Procedure: Conduct a field test by observing the stones over time for signs of degradation.
Purpose: To ensure that riprap is placed correctly in the field.
Procedure: Observe the placement of the riprap to ensure that it is compacted and properly interlocked Check for the required thickness and coverage as specified in the project plans.
Some necessary criteria will be tested or as per engineer's instructions:
Check for physical defects, such as tears, holes, or irregularities Verify the color, texture, and overall appearance of the geotextile.
Purpose: To determine the maximum tensile strength of the geotextile material.
Method: A sample of the geotextile is cut to a specified size and placed in a tensile testing machine The machine applies a force until the material fails, and the maximum force is recorded.
Purpose: To assess the geotextile's ability to resist puncture forces, which is critical for applications where sharp objects may be present.
Method: A puncture testing device is used to apply a force to a sample until it punctures The force at which puncture occurs is recorded.
Purpose: To measure the flow rate of water through the geotextile, which is important for drainage applications.
Method: This can be performed using a constant head or falling head method Water is allowed to flow through the geotextile, and the flow rate is measured to calculate permeability.
Purpose: To evaluate the geotextile's resistance to degradation from ultraviolet (UV) radiation.
Method: Samples are exposed to UV light for a specified duration, and then their physical properties (e.g., tensile strength) are tested to assess any changes.
Purpose: To determine the strength of seams in geotextile materials, which is crucial for applications where multiple sheets are joined.
Method: A sample with seams is placed in a tensile testing machine, and the force required to break the seam is recorded.
Purpose: To measure the thickness of the geotextile, which can influence its performance characteristics.
Method: A thickness gauge is used to measure the thickness of the geotextile at specified points.
Purpose: To assess the geotextile's resistance to various chemicals it may encounter in its application.
Method: Samples are exposed to specific chemicals for a defined period, and then their physical properties are tested to evaluate any changes.
CONSTRUCTION PROCEDURE
Work Flow Chart
The Work Flow Chart is shown in Figure 8.1-1 below.
Figure 8.1-1: Work Flow Chart of Grouted Riprap Slope Protection
Preparation Works
- Submitting construction method documents to consultants, Approved Construction Drawing.
- Testing and Inspection of materials supplied for works
- Arrange traffic safety control devices at the working area (See Figure 8.2-1)
Based on the actual current status of the construction site and construction organization measures and construction progress The storage yard for stone, sand, cement etc Depending on the location and time of construction, the construction unit will arrange it to suit the most effective progress and distance of transportation.
- Prepare water sources for construction:
The amount of construction water is calculated so that it is always economical, ensuring enough for the construction process The water source for construction is taken from river water and processed through settling tanks.
- Mobilizing construction machinery, equipment, and human resources to execute the works:
Based on construction volume and work content; Based on actual conditions, construction equipment capacity, and construction contractor's personnel; Based on the construction progress of the construction package The contractor will mobilize appropriate construction machinery and equipment to execute the works as shown Sub-Clause 5: “Manpower and Equipment”.
- In case of water presence on the area as footing foundation of Riprap Slope, dewatering system will be provided to eliminate the presence of water and to enable a dry working area.
Figure 8.2-1: Traffic Control for Construction Stages
Survey Works
- Prior to start the excavation works, setting-out points will be established at site by Surveyor.
- Lay out and elevation points will be indicated on the line and grade stakes installed at site for construction references.
- Any deviation found between actual site condition and approved shop drawing shall be informed to the Engineer.
- Temporary control points should be checked daily before the commencement of the work.
Road BM/ TBM Sta N (m) E (m) Elevation (m)
Slope Trimming, Excavation Works
Begin excavation to achieve the desired slope angle and elevation.
Use appropriate machinery to cut back the slope to the specified dimensions.
Remove excess soil and rock material from the site.
Stockpile or dispose of excavated materials as per project requirements.
- Excavation of footing foundation of grouted riprap slope:
Excavation works shall be undertaken using conventional Excavator combined with manual digging Remove excess soil and rock material from the site.
Complete height and size according to design requirements
Grade the slope to ensure a smooth and even surface.
Trim the slope to the specified angle, ensuring it is stable and suitable for riprap placement.
Inspect the trimmed slope for stability and make adjustments as necessary.
Figure 8.4-1: Slope Trimming, Excavation Works
Compaction of Footing Foundation of Riprap Slope
- Manual trimming, leveling bottom elevation of foundation After removal of excavation material is completed, foundation level surface will be compacted using tamping rammer or plate compactor to present a uniform surface true to line and grade conforming to the cross section shown in the approved drawing.
- If existing ground condition is unsuitable materials, it will be removed and replaced with approved selected materials as directed by the Engineer and compacted layer by layer to a density of not less than 90% of MDD.
Installation of Geotextile and PVC weep hole
- Provide geotextile and drain PVC weep hole in accordance project requirements
- Mark the location and install it correct as shown on the construction drawing
Figure 8.6-1: Installation of Geotextile and PVC weep hole
Mixing Construction Mortar
Mortar is mixed according to the required gradation and mixed with a 150l mixer The mortar mixer used has been maintained, repaired and tested to ensure certain operating and safety parameters.
- Prepare all necessary materials, tools and equipment.
- Mortar mixing must be based on needs at each time of construction.
- Mixed mortar ensures compliance with quantity and quality regulations Mixed materials must be weighed and measured accurately, and mixed mortar must be flexible according to design regulations.
- When transporting mortar by hand, the mortar container must be tight and sturdy so that the mortar does not lose water and ensure that the mortar does not separate If the mortar shows signs of separation, it must be mixed again before being used.
- Arrange forces and vehicles to transport mortar in accordance with the speed of mortar mixing and plastering work, ensuring that wherever the mortar is mixed, it is completely applied and the mortar does not stagnate.
- Inspection of mortar quality and masonry quality must be conducted regularly and concurrently with the construction process.
Figure 8.7-1: Mortar Mixing and Transportation
Construction of Grouted Riprap
Construction stone must ensure the correct size, elevation and must meet technical and artistic quality.
Before construction, make sure the stone is clean and moist enough During stone construction work, it is necessary to regularly monitor the quality of materials used and take remedial measures when necessary.
Use highly skilled workers to perform stone masonry work and take full responsibility for stone masonry techniques in the project However, in any case the following requirements must be met:
- Masonry stones of large size and weight must be placed in the bottom layers of the masonry structure.
- Stones built in the same layer must have the same thickness.
- The stones on the outside must be relatively large and flat.
- Alternating the stones in the same row or rows of stones together is a layer of mortar to ensure the connection and stability of the structure.
- The mortar joints between the masonry stones must be full of mortar, tight and watertight, and there must be no overlapping joints on the outside, inside and vertical joints of the masonry.
- When constructing high, thick and long stone wall structures, attention must be paid to ensuring construction progress and appropriate measures for handling construction joints The height of each wall segment and the difference in height between two successive wall segments must be controlled to ensure the bearing capacity of the newly built wall segment as well as uniform settlement of the building's foundation The wall was only built 1.2 ~1.5m high and then stopped for 24 hours before being built higher.
- When building, the stone must be laid flat The joints must be evenly filled with mortar, at most 3cm thick At the same time, the stones must not be built directly on top of each other It is strictly forbidden to place stone first and then pour mortar Do not use crushed stone to place stone in the outer joints.
- Do not build overlapping veins on the outside or in the masonry stone The vertical veins of the upper rock layer must be staggered with the vertical veins of the lower rock layer by at least 8cm.
Figure 8.8-1: Construction of Grouted Riprap
- In each layer of stone, build 2 rows of stones on the outside of the front wall and then building the rows of stones in the middle, the stones built on the outside of the wall must be relatively large in size and flat.
- When construction is temporarily stopped for a short time, the masonry part that must continue to be built is filled with mortar and crushed stone is inserted into all mortar joints of the masonry structure If the downtime is prolonged, measures must be taken to cover and water to maintain the surfaces of unfinished stone structures, especially in dry or windy weather conditions Before rebuilding these stone structures, the interface between the old and new masonry must be treated.
- At the end of the stone masonry work, it is necessary to ensure that there is no direct or close impact on the stone masonry structure during the setting time of the mortar and masonry to reach the design strength.
- If in locations where it is necessary to build soil around masonry structures, this can only be done when the structure is stable and capable of bearing the designed load In case you want to carry out earthworks earlier than the allowed time, the Unit must obtain the consent of the supervision consultant.
Figure 8.8-2: Construction Photo of Grouted Riprap
Masonry Curing
- To prevent the mortar from drying out and cracking while the mortar is setting, you must cover the surface of the masonry and water it with moist water Minimum curing time is 7 days; water must be watered so that all mortar joints are wet Masonry should only be exposed to running water after the masonry has reached its design strength.
- During the following period until the end of the prescribed construction warranty period, it is necessary to regularly monitor the condition of stone structures, promptly detect defects or damage and take remedial measures.
Site Restoration
As soon as the construction of Grouted Riprap is completed, Contractor will restore the site as closely as the original condition as possible and to the satisfaction of the Engineer.
QUALITY CONTROL
- QC Engineer shall inspect all work to ensure compliance to the requirement of Specification andDrawings.
- Strictly control of materials according to specifications and construction equipment All materials to be used for this work shall be subject to Engineer’s approval.
- Method statement: “Quality Assurance Plan” shall be submitted separately and shall be a part of this Method Statement.
Description: The completed construction items will be inspected by the contractor's field engineer The qualified items will be reported to the contractor's office by the field engineer The contractor's quality control department will plan to inspect the construction quality After the item meets the quality requirements and is approved by the contractor's quality director, the contractor will plan and notify the consultant about the joint site inspection between the contractor and the consultant After the consultant inspects and approves the work, the contractor will carry out the construction of the next work items in accordance with the construction phase All unapproved work items will be resolved and handled by the contractor so that the work items meet the project requirements The next work will not be constructed without the consent of the consultant.
TRAFFIC SAFETY CONTROL
Maintenance of Existing Road and Bridges
When public traffic is to be passed though the Works in an incomplete state the Contractor shall take all steps necessary to provide a smooth free-draining running surface and to maintain it in that condition.
The contractor shall ensure that the surface is neither excessively dusty nor dangerously slippery and shall, if directed by the Engineer, water the surface to lay dust or provide a thin gravel topping to the trafficked surface.
The Contractor shall ensure that safe access is maintained at all times across bridges and culverts within the limits of the site This may include the repair or replacement of bridge deck materials or the construction of a by-pass where more appropriate, but at all times the Contractor should not delay the passage of vehicles for excessive periods.
The Contractor shall render such assistance to the public as shall be necessary to allow safe and convenient passage of traffic at all times
Traffic Closing Basis
- Part of lanes shall be closed to execute without changing the directions of the traffic flow in the existing road A section shall be rationally divided based on the principles of facilitating the construction vehicles to enter or leave the site and the passing vehicles to pass smoothly.
- All traffic control measures shall be in operation 24 hours per day and shall be supplemented by lights at night when the Engineer considers this necessary.
- At least two weeks before he intends to alter trafficking patterns in any way the Contractor shall present plans to the Engineer for traffic signing and control If the Engineer does not approve these plans the Contractor shall make such amendments to them as are necessary in order to make them, in the Engineer’s opinion, satisfactory Prior to implementation of the new trafficking arrangements, the Engineer shall inspect the Contractor’s signs, barriers and signals and only when the Engineer agrees shall they be put into operation.
- Some typical arrangements for traffic safety control:
Site Layout
Part of lanes shall be closed to execute without changing the directions of the traffic flow, which is to say one or two lanes be closed, the rest is used to pass through.
The control area is divided into the parts: warning zone, buffer zone, operation zone and termination zone.
Warning zone: 200m-long warning zone shall be set, in which the signs of "Speed Limit",
"Operation Ahead", "No Overtaking", "Narrow Lane Ahead", "No Passing" shall be marked The space between adjacent signs shall be less than 30m, usually 10m to 30m The last sign is at a distance of not less than 15m from the first device (tapered sign) of the upper transition zone.
Buffer zone : The length of buffer zone is 8m The reflective cone is transited gradually to the traffic lane.
Operation zone: 0.l-0.5km-long operation zone shall be set as a construction unit, one half widths of which is closed for construction The tapered signs with interval of 2- 4m are placed on the sides of construction area.
Termination zone: The length of the termination zone shall not be less than10m The sign of
"Restored Traffic" shall be placed at the end of the termination zone.
The special person shall be appointed at the beginning and finishing end of the closed sections to direct traffic with a red flag.
Traffic Control of Blocked Sections
The construction of bridges or culvert or road section will affect the circulation of the vehicles on the Road, the contractor tends to occupy the entire road or a part of road Therefore, at each construction site and based on the actual conditions on the construction site, the contractor will propose a solution to block the entire road or a part of the road to serve the construction process of the items In case of blocking the entire road section, we will construct a detour or a plan to direct traffic on another suitable route to ensure two-way traffic according to technical requirements and limit congestion.
At locations where traffic needs to be blocked, the contractor will have a specific plan and discuss with the consultant before implementing the work. b) Some regulations of safety
- For construction personnel in accordance with the safety regulations for construction The Personal Protective Equipment shall be worn
- No drinking, slippers, and sandals are allowed on site.
- The insurance fee shall be paid on time and warning flashlights be installed for the construction vehicles.
- The traffic rules shall be com plied with and no parking on the lane or turning around randomly be permitted for construction vehicles.
- A full-time safetyman shall be arrangement to supervise the execution of the project.
- The finished sections shall be protected carefully, and roadblocks or warning signs shall be placed if necessary.
- The damaged safety signs which affect the expression of the safety information shall be replaced in time.
- Safety signs shall be placed in bright environment and at a proper distance from the danger location so that the relevant people have enough time to note the information that it represents.
- The safety signs with dirt, grease shall be cleaned timely to ensure the safety information without the mistakable messages.
- The safety signs with displacement shall be adjusted in place to avoid accidents, which result from the relevant people's not quickly noticing and understanding the safety information.
ENVIROMENT AND SAFETY CONTROL
Safety Control
Prior to starting of construction works, warning signs and instruction boards shall be fully installed either inside or surrounding the construction site and the following particular matters are to be through to all members working in the construction site in order to complete the work efficiently without any accident or casualty. a) Joint Meeting
- Prior to start any activity, a joint meeting with relevant staffs shall be held for the purpose of general explanation on the whole contents of works as well as the method for the implementation of efficient work. b) Basic Instruction
- All workers shall always wear Personal Protective Equipment (PPE), such as hardhat (helmet), safety shoes, hand gloves and working uniform. c) Prevention of Accident by Heavy Machine
- Only skilled operator shall be allowed to operate equipment on site In case of new operators, a test of skill shall be conducted first prior to his acceptance to the job Preventive maintenance check shall be done regularly at equipment working at site prior to full operation Stability of working area and foundation of equipment shall be checked particularly at locations of outrigger and track pad of cranes. d) Prevention of Accident of Electrocution
- Electric generating equipment shall be properly protected and properly installed with earth connection Electric wires shall relate to electrical tapes to prevent electric leakage Only skilled operator shall be allowed to operate equipment on site. e) Prevention of Accident in Night Shift Works
- Enough lighting system shall be provided for night shift works especially installed at working platforms If necessary, all the surrounding working area shall be lighted up The people who work on the site must wear reflective jacket, if worked at night. f) Existing Facilities
- Existing facilities especially existing overhead electric line, water line, telecommunication line and other important facilities at surrounding area shall be taken with care not to damage.
Environmental Control
Responsibility for surrounding environment during construction and shall comply with the Condition of Contract on Protection of Environment.
If any other problems occurred in the site, applicable counter measures or prevention action shall be considered immediately and executed as soon as possible.
The Contractor shall be responsible for implementing and managing mitigation measures during the construction of the Works The recommended mitigation measures are presented below. a) Ambient air quality
- Exhaust emissions from construction equipment shall be strictly controlled in accordance TheContractors are requested to use standard equipment.
- Where possible the Contractor ’s chosen access routes to and from the site should avoid residential areas Vehicles carrying sand, aggregates or other loose materials shall be fully covered Brushing and watering shall be used where required to control dust and the spraying of mud.
- Stockpiles should be covered or kept damp to avoid windblown dust.
- The Contractor shall be co-ordinate his activities with local environmental management authorities to control and supervise the ambient air quality within the program of regional pollution control.
- Spraying Water for Dust Control: To protect the passenger and the residents from dust during construction period, the Contractor shall spray water along the road at least two times per day except rainy season or directed by the Engineer b) Noise and vibration level
- The Contractor shall use equipment and facilities conforming to Standards for traffic noise level
- In order to protect residents’ houses, public buildings and other structures, the maximum vibration at these locations should ensure the allowable range. c) Water environment
- To ensure the water quality of local watercourses, ponds, and lakes the Contractors shall comply with the following environmental protection measures Care shall be taken with fuels and oils.
- No waste material of any kind shall be disposed of into local watercourses, ponds, or lakes.
- Stationary construction equipment, offices and accommodation, workshops and storage areas and other temporary facilities shall not be located near to local watercourses, ponds, and lakes.
- Oil waste shall be collected, treated, and disposed of in approved disposal areas.
- Fuels and oils shall not be stored nearly local watercourses, ponds or lakes and shall be stored in areas located at least 200m away from such water features.
- Oil and fuel storage tanks shall be at an elevation higher than the flood level Warning signs shall be installed at all fuel storage areas to avoid collision with construction equipment.
- Suitable temporary drainage should be provided to prevent localized flooding or contaminated run-off from the site and to ensure construction work is not damaged or delayed by standing water.
APPENDIX
Some Photo of Main Equipment/ Tools used in Construction
Mini Concrete Mixer Water pump