1. Compilation basis
1. 1. Design data of hydraulic protection project site: Gas -B0 1024 general construction drawing of hydraulic protection project site design;
Line; 1792 line; 1794 line; 1795 line; 1796
1.2. Standard Specification GBJ202-83 Code for Construction and Acceptance of Foundation and Foundation Engineering GB50203-98 Code for Construction and Acceptance of Masonry Engineering GB50026-93 Code for Engineering Investigation GBJ206-83 Code for Construction and Acceptance of Timber Structure Engineering JGJGJ46-88 Safety Technology for Temporary Electricity Use in Construction Site
2. General situation of the project and main quantities
2. 1. General situation of the project: this section meets from west to east, and the starting point of the line is measured with the pile number BI00 1 (abscissa y= 1765 1070.38, ordinate x=430668 1.26). X=4258240.82), and the final line length after line adjustment is 89.4008km. There are mostly plains along this section, mainly alluvial plains and alluvial oblique plains, and hilly areas are mainly concentrated between BI0 18# pile and Bi022 # pile, with mountains as the main ones. Hydraulic protection mainly includes slope protection and revetment of river canals and gullies, retaining walls and drainage ditches in steep mountains. Retaining walls are set on the earth ridges and steep slopes; For banks with unstable soil and serious erosion of the main river, retaining walls are adopted; For the river bank or beach with stable water flow and small erosion, the slope protection with mortar rubble can be adopted. Cohesive soil slope, backfill soil should be compacted by layers (compaction coefficient is generally 0.90); When the pipeline is laid by climbing embankment, the side (or both sides) facing the water surface and the river bank are protected by mortar rubble, and the channel with rubble or cement is restored to its original appearance, which is the same as the original protection method; For slopes with a slope angle greater than 15, a retaining wall and drainage ditch shall be built every 10m.
2.2. Name of soil and water conservation structure of main projects at present. General engineering number unit drawing. Masonry slope protection 180.5m3 line-1795 continuous concrete protective layer 52m line-1795 water retaining ridge 82 line-1795 drainage ditch 37 line-1795 mortar rubble crosses the water surface.
3.2. Construction method: The single quantity of hydraulic protection project is relatively small, and at the same time, in order to avoid damaging the pipe body, the foundation pit groove is excavated manually in the construction, and the wall groove is excavated manually in the rocky section. Submersible pump is used for foundation pit dewatering, generator generates electricity on site, mortar is used for manual masonry, and lime-soil formwork is used on site.
4. Construction technical measures
4. 1. Material selection and technical requirements Hydraulic protection is a line engineering protection facility, which is of great significance to the protection of pipelines in use. Therefore, the technical requirements for hydraulic protection materials are very strict, and strict selection and acceptance must be carried out. Material procurement should adhere to the principle of adapting measures to local conditions, ensuring quality and reducing costs. Materials entering the site must have material certificate, certificate of approval and relevant certificates, and unqualified products and unlicensed products are prohibited from entering the construction site.
4. 1. 1. Masonry (mainly stone) with slurry masonry shall be made of stone with uniform texture, consistent hardness, no cracks and no weathering, and the surface of the stone shall be free of weathering debris, mud marks and dirt. The ultimate compressive strength should be above 25Mpa. When laying, try to choose larger stones, which should be roughly square without sharp corners. Sheet should have two roughly parallel faces, the thickness of which should not be less than 15cm, and the length of one face should not be less than 30cm. The stone used for hydraulic protection of the West-East Gas Pipeline is mainly block stone, and the stone area in the construction section is mostly wind fossil, which does not meet the technical requirements of soil and water conservation masonry. Therefore, the construction stone should be mainly purchased, and the purchasing place is selected in Shandan quarry, with the nearest transportation distance of 26Km and the longest transportation distance of 82km.
4. 1.2. Masonry mortar? Firstly, according to the design requirements, qualified sand and cement are selected, mortar is mixed with tap water, and it is purchased from Shandan County with 5T water truck and delivered to the site, with an average transportation distance of 38Km. It is forbidden to take sewage from the ditch anywhere. R425 ordinary portland cement for cement was purchased in Shandan Cement Plant. The cement entering the site must have the factory certificate, test report and re-inspection report, and its stability, setting time, strength and other indicators must meet the standards, with an average transportation distance of 39Km. Sand is washed medium (fine) sand, which is purchased from Shandan battlefield. Sand and gravel can only be put into use when their mechanical properties meet the standards, with an average transportation distance of 29Km? Cement used in the construction site shall be neatly stacked, with the stacking height of bagged cement generally not exceeding 10 bag, and the stacking width limited to 5- 10 bag. Temporary open-air stacking should be covered with rain-proof tarpaulin. ? In general, the storage time of cement is less than 3 months. If there is doubt or uncertainty about the quality of cement, the test should be rechecked before use and used according to the test results. ? Sand and cement used at the site shall be stacked neatly separately and shall not be mixed. Sand should be kept clean, and it is forbidden to mix with soil. ? Mortar for masonry must have timely fluidity and good workability to ensure the fullness and compactness of masonry mortar joints. ? The simple on-site inspection method is to knead it into small balls by hand, so that it can't seal the slurry and won't loosen after being released. ? The label of mortar used for masonry in different construction sites and different structural forms is strictly controlled according to the design requirements, and mixed mortar is strictly prohibited for masonry walls. ? Masonry mortar shall be inspected quantitatively and in batches, and a set of specimens for evaluating mortar strength shall be made for the masonry with the maximum size of 100m3. When the variety, label or mixture ratio of cement changes, another set of specimens should be made as the basis for measuring the quality of mortar.
4. 1.3. Board of Directors? The choice of wood depends on the place, and the principle is that it must be hardwood. We choose better quality pine, which comes from the timber market in Zhangye City. ? Rigid nails are used to connect the vertical plate of the cutoff wall with the wallboard. ? Use an electric drill to drill the drain hole of the plate, and the drilling position should be staggered by 200 mm from the joint of the plate.
4. 1.4. Masonry lime soil? 3: 7 lime-soil cutoff wall is used in the West-East Gas Transmission Project. Before mixing lime soil, lime, soil and mixing water must undergo strict inspection, sampling and testing, and lime soil can be prepared only after it is qualified. ? Lime soil shall be stirred mechanically and evenly, and each batch of lime soil shall be sampled and tested in proportion to ensure that the water content is the best. The field inspection shall be based on "holding the ball and blooming on the ground". ? Layered compaction should be adopted, with a layer of 30cm as appropriate, and the compaction coefficient should be ≥0.94. The soil and water conservation in this bid section is mostly located in Gobi desert and rocky areas, and the fine soil mixed with lime soil is difficult to borrow, so it is necessary to buy soil materials from the local area. According to the combination with the local government, Shandan Brick Factory was selected as the borrow site, and dump trucks were used to pull the soil, with an average transportation distance of 32km. Drinking water is used for mixing water, which is purchased from Shandan county by tanker and transported to the site, with an average transportation distance of 38 kilometers.
4.2. Structural measurement and positioning? Generally, theodolite is selected as the measuring and positioning instrument, and total station is selected for the positioning measurement of structures crossing the steep slope of Dachonggou. Theodolite and total station can only be used after recalibration, and instruments must be submitted for inspection before construction, with calibration certificate. ? Reference point selection, structural measurement and positioning, engineering coordinates and elevation are all quoted from the coordinate points of pile points in pipeline blueprint design. ? When setting out, use theodolite to measure the position of each corner of the structure, and bury control piles as the basis for future construction positioning and pile location transfer, and draw sketches on site for the record.
4.3 Excavation and protection of trench in foundation pit
4.3. 1 trench excavation of foundation pit According to the position of positioning piles and the size of structures, the edge of foundation pit is released with white lime, and then the foundation pit is excavated. In order to avoid damaging the pipeline anticorrosion layer and even the pipe body during excavation, all foundation pits are excavated manually. The hydraulic protection position of this bid section is located in rocky mountain areas and river valleys, and the excavation of foundation pit trench in rocky areas adopts manual drilling.
4.3.2 Foundation pit dewatering protection Mountain area is adjacent to Qijiadian Reservoir, and groundwater will be collected during foundation pit excavation in some areas. Therefore, dewatering measures should be taken at any time during trench excavation of foundation pit, and the water in the foundation pit should be pumped out by submersible pump and discharged into the pre-dug catchment ditch, and the section of the catchment ditch should be discharged by the catchment ditch.
4.4. Mortar masonry
4.4. 1 technical requirements for masonry? Masonry masonry wall adopts staggered masonry method, which is laid horizontally by hanging double lines according to the shape of stone. The first layer of stone faces downwards, and the upper and lower stones are staggered, with internal and external overlapping, stable masonry and layered masonry. ? Mortar masonry should be built by mortar masonry method. Mortar joint should be full and dense. Mortar joints are generally 20-30 mm, and the thickness of mortar is about 40-60 mm Gravel blocks should be embedded in mortar for larger gaps, and it is not allowed to fill gravel into mortar first. ? Mortar blocks shall not form horizontal or vertical joints and shall not be twisted. ? When filling the abdomen with stone, the horizontal mortar joint width shall not be greater than 3cm, and the vertical mortar joint shall not be greater than 4cm. The mortar joint of rock filling should be staggered. ? If there are no special requirements, the masonry surface shall be marked with jointing. If there are no special requirements, an empty joint with a depth of 2cm shall be set aside during masonry, and then the joint shall be plastered with cement mortar. Otherwise, the empty joint shall be cleaned up before marking. ? Masonry surface jointing adopts flat joint, and the mortar label used for jointing is not lower than that of masonry mortar. ? Masonry masonry is completed at one time, and construction joints are not allowed to be left at will.
4.4.2 monomer masonry measures? Before mixing lime soil in the reservoir, dig the reservoir at the construction site in advance and prepare the construction water. The size of the reservoir depends on the amount of lime and soil in this site, and the water consumption should be fully met. The inner wall of the reservoir is lined with two layers of plastic sheets, the size of which should cover the top of the reservoir to prevent evaporation and sundries from falling into the pool. ? Masonry slope protection? In the hydraulic protection of west-to-east gas pipeline, the pipeline crosses the river or gully in the form of masonry slope protection, and the masonry of slope protection adopts block stone. ? The foundation trench of slope protection is excavated manually, and the basal plain soil is compacted, and the compactness coefficient reaches 0.9? Mortar blocks shall not form horizontal or vertical joints, and shall not be distorted, and the mortar shall be full. ? If there are no special requirements, the masonry surface shall be marked with jointing. If there are no special requirements, an empty joint with a depth of 2cm shall be set aside during masonry, and then the joint shall be plastered with cement mortar. Otherwise, the empty joint shall be cleaned up before marking. ? Masonry surface jointing adopts flat joint, and the mortar label used for jointing is not lower than that of masonry mortar.
4.5. Completion acceptance
4.5. 1 Before the pre-acceptance of the project, the contractor shall organize relevant personnel to conduct a comprehensive inspection of its construction project according to the requirements of design and construction drawings and construction standards, and rectify any discrepancy immediately.
4.5.2 When all the projects are completed and conform to the provisions of the contract, the contractor shall apply to the owner or supervisor for completion acceptance.
4.5.3 The problems raised by the contractor in the pre-acceptance of the owner or supervision institution shall be rectified within the time limit specified by the owner or supervision institution, and a new application for completion shall be submitted.
4.5.4 The completion data shall be accepted by the owner or supervisor, and the completion data shall be handed over after acceptance.
5. The rainy season construction technical measures
5. 1 During rainy season construction, technical measures for rainy season construction should be carefully formulated, and specific grading implementation measures and regular inspection system should be formulated according to actual construction conditions, so as to facilitate the implementation of technical measures for rainy season construction.
5.2 According to the actual situation of site layout, do a good job of drainage on the construction site in time.
5.3 Protection of temporary facilities and site construction equipment:
Temporary facilities on the construction site should be renovated and reinforced before the rain period to ensure no leakage, collapse, collapse and no water around. Mechanical and electrical equipment (switchboard, brake box, welding machine, pump, etc. ) The construction site should have reliable rainproof measures (such as building a fortified canopy or building a simple electromechanical room, etc. ). At the same time, the power cord of electrical equipment should be hung and fixed, and it cannot be dragged to the ground. The rain-proof, leakage-proof and grounding protection devices of field electrical equipment should be sensitive and effective, and a special person should be responsible for checking them at any time. Before the rainy season comes, the lighting and power lines should be inspected for mixed wires, electric leakage, pole corrosion, firm burial, etc., to ensure normal power supply during the rainy season.
5.4 Raw materials, components and equipment that are afraid of rain, moisture and corrosion should be placed indoors, or stacked on a solid foundation in a higher place, or treated separately by taking measures such as tightly sealing tarpaulin.
5.5 Masonry works:
During the construction of masonry projects in rainy days, mortar should be prevented from being washed by irrigation and rain, and the consistency of mortar should be appropriately reduced. It is not advisable to leave construction joints in masonry. After the work, the masonry surface should be covered. Mortar for masonry should be mixed and used. When the highest temperature in construction exceeds 30℃, it must be used within 2 hours and 3 hours after mixing.
5.6 Mortar works:
Construction of mortar works in rainy days may cause moisture in construction raw materials (sand, cement, etc.). ) Due to the increase of rainfall, the mortar mixture ratio should be adjusted according to rainfall; For mortar construction after rainy days, the mortar mixture ratio should be readjusted after the moisture content of raw materials is determined. In the process of mortar transportation and masonry, if the rainfall is too large, the transportation equipment and pouring place should have rain-proof measures to avoid the fluidity and workability of mortar changing due to rainfall during transportation and pouring.
6. Site quality management system
6. 1 The quality controller shall observe, supervise and inspect the quality-related activities on site. Check whether the on-site construction work is carried out in accordance with the approved procedures.
6.2 On-site inspection activities are random and have no special reasons. In principle, they should be done every day. The deficiencies or defects found by observation shall be recorded and the responsible party shall be informed in written or oral form according to their importance.
6.3 Every weekend, the Technical Department summarizes the inspection situation, puts forward opinions and reports, and ensures that key projects and important working procedures are not missed.
6.4 The project site shall hold a quality summary meeting attended by all departments and project managers once a month. At the meeting, the technical department reported the operation of the quality system in that month, found the existing problems in time, and urged the departments with problems to actively take corrective measures and pay close attention to rectification.
6.5 All quality problems found on site shall be recorded in the format specified in the procedure document, and gradually handed over to the next stage as the project progresses, as a record document to prove that the quality meets the requirements in the completed state.
6.6 When the quality system conflicts with the quality management documents or cannot be implemented on the project site, it shall be reported to the company in time to solve the problem in time.
7. Site HSE management
7. 1. site
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7. 1.2 If there is danger that endangers or may hurt people, all related work shall be stopped until the dangerous state is eliminated.
7. 1.3 Any equipment and tools showing unsafe factors must be stopped immediately until they are in a safe state or removed or replaced from the construction area.
7. 1.4 In case of an accident at the site, emergency measures shall be taken immediately, and a written report shall be submitted to the owner at the first time, and investigation and handling shall be conducted according to the relevant regulations of the owner and supervisor and the company's accident handling procedures.
7. 1.5 The main roads on the construction site shall meet the requirements of standards, and cover plates and safety guardrails shall be set in special circumstances.
7. 1.6 The construction site shall be equipped with fire-fighting facilities and equipment according to the fire-fighting requirements to keep the fire-fighting passage unblocked.
7. 1.8 When construction is carried out at night, the project department will provide equipment with sufficient lighting intensity after approval by the supervisor to ensure safe production.
7. 1.9 The electrical switch and knife of the control box should be placed in a rain shelter or a rain cover, and a leakage protector should be set to prevent leakage.
7. 1. 10 The job site should be cleaned frequently and kept clean. Garbage should be piled up in a centralized way, cleaned in time and transported to the designated place.
7.2 Construction personnel
7.2. 1 Be familiar with the legal responsibilities and obligations related to safety and health, and the details of the comprehensive and integrated safety and health procedures of the project department.
7.2.2 Relevant personnel who violate safety regulations will be punished according to relevant regulations of the Project Department. Those who violate safety regulations and endanger the safety of life and property will be removed from the construction team.
7.2.3 Before work, the construction personnel shall wear protective articles suitable for operation according to regulations, check the working site and the intact conditions of construction machinery and equipment, and record the date of each inspection, problems found and remedial measures taken.
7.2.4 Construction personnel shall abide by the operating rules of post safety technology in their work, so as to achieve civilized construction.
7.2.5 Construction personnel shall not eat alcoholic beverages before and during work, and shall not smoke in places where fireworks are prohibited.
7.2.6 In the construction area, you should take the designated passage, not cross the dangerous area, not climb up and down on the moving motor vehicle, and not climb the crane hook and lifting objects.
7.2.7 Attention should be paid to all kinds of safety signs, and all kinds of lighting, signal, lightning protection and other safety protection devices, safety signs and testing instruments should not be removed or occupied at will.
7.2.8 In case of accident, rescue personnel and property in time, protect the site and report to relevant personnel. Implement the handover system.
7.3 Power safety
7.3. 1 The electrical work on the construction site shall be operated by full-time electricians according to the specifications. And be responsible for the leakage inspection of all kinds of live equipment and wires in the operation area, and immediately rectify the problems when found.
7.3.2 Operators of electrical equipment must wear qualified labor protection clothing and standard insulating gloves, and the electrical equipment must be tested for leakage before use.
7.3.3 In rainy, snowy or humid weather, electrical equipment is generally not used in the open air, and appropriate safety measures should be taken when necessary.
7.3.4 The electrical facilities on the construction site shall be provided with leakage protection devices at the head end of the equipment load line. The leakage protector shall be installed in the switch box.
7.3.5 The power distribution room on the construction site should be well ventilated, and measures should be taken to prevent rain, snow and animals from entering.
7.3.6 The metal shell of electrical equipment (except safe voltage) shall be grounded or connected to zero. Under wet or particularly harsh conditions, the electrical equipment on the construction site should be grounded with protection.
7.3.7 Various distribution lines on the distribution panel (panel) shall be numbered and marked with the purpose. During the maintenance of distribution lines, a warning sign "No closing, manned operation" should be hung. Stop, someone must be in charge of power transmission.
7.4 Other safety measures
7.4. 1 When carrying stones, we should pay attention to cooperation, coordinate the pace and exert force evenly to ensure safety.
7.4.2 Pay attention to safety when making gabions, and be careful not to slip skin and hook clothes when tying wires.
7.4.3 The construction access road shall have sufficient width and strength to ensure transportation safety.
7.4.5 When manually excavating the foundation trench, be careful not to slip the pipeline coating, and when manually drilling, prevent the operator from being injured by the collapsed stones.
7.4.6 When the cofferdam is used for diversion, it should have sufficient strength to prevent it from being washed away by water.
7.4.7 When the slope is protected by masonry, the stones on the slope surface should be cleaned to prevent the stones from slipping and hurting people.
7.4.8 When operating the mixer, the operating procedures shall be observed, and it is forbidden for non-post personnel to operate illegally.
7.5 Soil and water conservation measures
7.5. 1 The feed access road and yard should make full use of the construction work area or the existing rural gravel road. , there must be no sand and gravel yard with vegetation and the site where vegetation has been destroyed.
7.5.2 During the construction period, appropriate measures shall be taken to ensure that roads, slopes and others on site will not form obstacles to the ground, causing floods and destroying vegetation.
7.5.3 Trees cut down at will outside the operation area shall be remedied immediately. When safety and constructability permit, the staff who level the site can cut off the plants from the ground without damaging the surface of the site and touching the original roots, thus creating conditions for re-germination and growth in the future.
7.5.4 When excavating the trench, the topsoil and subsoil should be piled separately, and appropriate trench drainage should be set up to maintain a safe passage through the trench, so that the excess water in the trench can be pumped to the adjacent area in a way that does not affect the use of other land.
7.5.5 When backfilling the trench, the original shape of the surface should be restored as much as possible, so that the surface can be drained normally.
7.5.6 Backfilling of subsoil and topsoil shall match the soil layers on both sides of the trench. Before backfilling of subsoil, the reserved topsoil shall not be filled into the trench.
7.5.7 When backfilling the excavated soil, the surface turf or topsoil shall not be removed.
7.5.8 Tamp the backfill soil in the pipe trench, and the degree of compaction should be roughly equivalent to the state before construction, so as to minimize settlement. Pay attention to the compaction of fill at the intersection of pipe trench and waterway and on both sides of intermittent drainage ditch, and take appropriate measures when necessary to ensure construction safety.
7.5.9 Before backfilling, the excavated trench must be inspected with naked eyes. If you find animals, you should take them out. For larger animals, you can dig a slope on the wall and let them climb out.
7.5. 10 Keep the minimum vegetation buffer zone between the borrow site and any water area.
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7.5. 12 Except for the designated yard, pebbles, sands and wastes shall not be dumped or excavated from the riverbed or shore at will during the construction period without the permission of the local competent department.
7.5. 13 Destroy, move or clean up trees and vegetation, which shall not exceed the scope required by the project construction, and shall not be hacked indiscriminately.
When the road is temporarily widened and reinforced during construction, the original appearance should be restored according to the local actual situation after construction.
7.5. 14 If environmental damage is caused by violation of environmental laws and regulations, it shall immediately report to the project supervisor, who shall be responsible for cleaning, recycling and/or taking recovery measures according to the instructions of the project supervisor. The surface runoff gathers radially, and an annular throttling drainage ditch is set at the upper part of the gully, and a water cutoff wall is built along the gully on the slope.
7.5. 15 For the gully slope with poor stability, the soft soil foundation is protected by mortar rubble.
7.5. 16 In the process of river bed excavation, according to the requirements of the specification, on the premise of ensuring the working surface and construction surface, minimize the damage to the ecological environment of the river bed. After the river bed excavation is completed, the sundries that hinder flood discharge should be removed.
7.6 Waste and domestic garbage disposal
7.6. 1 Keep the garbage and sundries generated by construction in the work area.
7.6.2 Clean up the food waste at the work site every day.
7.6.3 Garbage shall be properly disposed of at the appropriate garbage disposal site outside the construction site.
7.6.4 Garbage shall not be discarded in ditches, topsoil or mounds.
7.6.5 The cleaning personnel shall clean up the garbage, sundries and cut branches, and deal with the construction expectation. Collect solid waste and garbage (non-biodegradable garbage) and treat them off site.
7.6.6 Collect solid waste and garbage (garbage that can't be degraded by dust) and treat it off site.
7.6.7 All kinds of oil should be stored in containers, and waste oil should be recovered in time for centralized storage. It is forbidden to dump on the spot, and measures should be taken to clean up when oil pollutes the ground.
7.6.8 Trees cut down in the cleaning process can be transported out of the operation area, or sliced, chopped or stacked in a convenient place for public use.
7.7 For emergency first aid before hydraulic protection (or construction operation) starts, on the basis of risk and hazard analysis and investigation of local common diseases, infectious diseases and hospitals, in view of the dangerous factors such as the environment where poisonous snakes haunt, the use of mechanical equipment and the drainage of generators, emergency plans and procedures are formulated, emergency teams are set up, and emergency materials are prepared to ensure that every employee is familiar with emergency plans and emergency actions in case of emergency.
7.7. 1 electric shock rescue? If the power switch is nearby, turn off the power supply quickly, otherwise, disconnect the wires or electrical appliances with insulation to separate the patient from the power supply; ? Stop breathing and give artificial respiration immediately; ? Cardiac arrest, chest compression; ? Send to the hospital for emergency treatment.
7.7.2 The principle of rescue and treatment for mechanical injuries is to save the lives of the wounded first, and the wounded who have stopped breathing and heartbeat should be immediately resuscitated on the spot. ? Treat asphyxia. If there is serious blood loss or open chest injury, stop bleeding or seal the chest wound as soon as possible; ? Treatment of shock and fracture fixation. To transport the wounded with limb fracture, the injured limb must be fixed with splint, and the spinal fracture must be lying on a hard bed; ? If there is arterial bleeding, put on a tourniquet, relax once every 1 hour, and keep the respiratory tract unblocked during transportation. ? Send to hospital, prevent infection, correct electrolyte metabolism disorder and inject tetanus antitoxin.
7.7.3 First aid for acute poisoning? Stop contact with poison immediately. When the poison invades from the respiratory tract or skin, the patient should be evacuated from the poisoning site immediately and moved to a place with fresh air. Contaminated clothes must be taken off immediately and the skin in the contact area must be cleaned. ? Take vomiting, gastric lavage, catharsis and other methods to remove the unabsorbed poisons in the body; ? Remove poisons from the skin, take off contaminated clothes, and wash the skin and hair with plenty of warm water; ? Remove toxic substances from eyes and rinse thoroughly with clear water; ? Remove toxins from wounds; ? Take the antidote to the hospital.
8. Personnel organization
9. Labor quantity and usage plan
10. Structure diagram
August 2003 1 started the hydraulic protection construction, and completed the hydraulic protection of each section in time according to the construction speed of the main pipeline.
1 1. Demand plan of main materials and machinery.
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