Chapter I Compilation Description and Basis
1. 1 compilation description
1. 1. 1 Our company adheres to the concept of serving users, and the preparation of construction organization design focuses on improving engineering quality, speeding up construction progress, paying special attention to safe and civilized production and providing favorable guarantee. Create a good environment for customers. Establish a good social image.
1. 1.2 Our company attaches great importance to the preparation of this construction scheme design, and the technical director of the company will organize the key, difficult and key special procedures of the project to tackle key problems. On the premise of carefully studying the drawings, clarifying the engineering characteristics, fully understanding the construction environment and accurately grasping the requirements of the owner, a special group is set up to brainstorm and learn from others, so that the scheme is focused, feasible, advanced in thought, operable and targeted.
1.2 compilation basis
1.2. 1 According to the Law of People's Republic of China (PRC) on Work Safety, the control of dangerous point sources in construction projects should be strengthened to avoid serious accidents.
1.2.2 According to Article 1 of the Interim Measures for Safety Management of Deep Foundation Pit Construction in Luoyang Construction Engineering, in order to strengthen the safety management of deep foundation pit construction in construction engineering, ensure the safety of deep foundation pit and adjacent buildings, underground facilities and roads, and prevent the occurrence of safety accidents, the construction scheme is determined according to the provisions of relevant laws and regulations and the geological conditions and surrounding environment.
1.2.3 According to Code for Acceptance of Construction Quality of Building Foundation Engineering (GB 50202-2002)
Chapter II Project Overview and Characteristics
2. 1 Site location and topography
2. 1. 1 The project construction site is located in the courtyard of Luoshu Anju Community. The site is relatively open, the "three links and one leveling" is smooth, the road traffic is convenient, and the construction conditions are available.
2. 1.2 The whole construction site is free from the interference of vehicles and pedestrians, and the construction around the project is closed, with four import and export gates.
2. 1.3 The project is flat and the obstacles are cleaned, which is basically beneficial to the construction.
2. 1.4 The foundation of this project is excavated with a basement.
1. The excavation depth of this project is about 4m. The construction is difficult, so effective measures must be taken to ensure the construction quality and safety.
2. As the foundation of this project is the foundation of Sanqi lime-soil cushion, effective measures must be taken to ensure the construction quality and safety.
2. 1.5 According to the Interim Measures for the Safety Management of Deep Foundation Pit Construction in Luoyang Construction Engineering, the buildings, municipal infrastructure and roads within the range of 2 times the excavation depth outside the sideline of deep foundation pit excavation area must be reinforced.
Chapter III Construction Preparation
3. 1 machinery and equipment
1, machinery: 1 excavator; 1 50 loader; Drum; 4 dump trucks;
2. Machines and tools: trolleys, shovels (with pointed heads and flat heads), steel tape measures, ladders, slope scale, ropes and other special construction machines and tools.
3. Safety maintenance: 1.5m guardrail wood main pole, safety warning rope, safety warning sign, warning light, colored strip cloth, bracing plate, bracing wood and square wood.
3.2 Operating conditions
1. Before earthwork excavation, remove the underground and ground obstacles in the construction area according to the requirements of design drawings and construction scheme.
2. All kinds of existing pipelines have been moved or reinforced, and the untreated underground pipelines and dangerous areas should be clearly marked.
3. When there is groundwater in the foundation pit, measures should be taken to reduce the groundwater level according to the local engineering geological data, and the water level should be below 0.5m at the bottom of the pit.
4. The water supply, power supply and temporary facilities in the construction area meet the requirements of earthwork excavation, and the roads are unimpeded.
5. Do a good job in the maintenance, inspection and entry of earthwork excavation machinery, transport vehicles and various auxiliary equipment.
3.3 Technical preparation
1. Before excavation, carefully review the design drawings and descriptions, complete the blue prints.the design and construction organization design, determine the excavation section and pile soil position, and transport the construction road.
2. Make a written construction safety technical disclosure to relevant personnel and sign it.
3. The survey sideline of foundation pit excavation has been released and marked with white ash. Determine the earthwork stacking site and earth-moving construction route.
Chapter IV Technical Measures for Construction
4. 1 process
Measuring and setting out → basement excavation → retaining wall construction → trench inspection → plain concrete cushion → Sanqi lime-soil cushion → plain concrete cushion → reinforced concrete strip foundation → basement foundation leveling.
4.2 Construction sequence
1, determine the excavation depth.
2. According to the general situation of the project, conduct on-site investigation and exploration, and analyze the characteristics of the project.
3. According to the survey data of the base area, slope excavation is adopted for the foundation pit. According to the classification of soil and whether there is static and dynamic load on the top of slope in Code for Design of Building Foundation.
4.3 Construction Technology
1. The excavation of foundation pit adopts the method of layered excavation and manual slope repair to check the bottom. 1: 0.3 within 3m of the slope, 1: 0.5 between 3m and 5m, and 1: 0.2 from the excavation line to underground facilities and roads near the slope.
2. The undisturbed soil of 0.2m—0.3m above the design elevation of the foundation pit bottom shall be kept, and it is forbidden to disturb and manually clean it. If there is local overbreak, it should be backfilled and compacted with gravel.
3. Considering the location of the basement of this project, mechanical excavation is the main method of foundation pit excavation, and manual excavation is adopted near underground facilities, and the method of manual trimming and bottom picking is adopted.
4. When digging the foundation trench, the elevation of the basement shall be strictly controlled, and overbreak is strictly prohibited. Undisturbed soil 0.3m above the design elevation of the basement shall be cleaned up to the design elevation by special personnel. If there is local overbreak or disturbance, it must be replaced with natural graded sand or medium coarse sand, and the filling elevation is 10 ~ 15 mm, and compacted.
5. If there are stones, gravel, bricks and other hard objects in the basement, they should be removed to 0.2m below the design elevation, then paved with natural graded sand materials, and the surface layer should be leveled and compacted with sand.
6, when the foundation pit excavation, excavation process should not be exposed for a long time, should be a period of excavation, a period of construction, dry groove construction is prohibited.
4.4 Preventive measures
1. Overexcavation of foundation pit: the excavation of foundation pit shall not exceed the elevation of foundation pit. If some places are overbreak, the treatment method should be approved by the design unit.
2. The basement is unprotected: the disturbance to the foundation soil should be minimized after the foundation pit excavation. If the foundation can't be constructed in time, you can reserve 30cm soil layer above the basement elevation and don't dig until the foundation is ready.
3. Unreasonable construction sequence: Earthwork excavation should be carried out in strict accordance with the construction sequence specified in the construction plan, and attention should be paid to the excavation from a lower place first, and it should be carried out in layers and sections in turn to form a certain slope.
4. Insufficient excavation size and large slope: the excavation width and slope at the bottom of the foundation pit should not only consider the structural size requirements, but also increase the width of the working face according to the construction needs.
5. Before foundation pit excavation, the construction sidewalk or road should be paved with slag or sand.
6. Earthwork excavation is carried out by excavator. First, the surface layer is excavated, and then excavation is carried out at a certain slope rate according to the design depth of foundation pit. During excavation, 30cm shall be reserved for manual bottom cleaning and leveling to avoid disturbing the undisturbed soil of the foundation trench.
4.5 rainy day construction measures
1, in order to ensure the engineering quality and prevent the occurrence of safety accidents, some engineering projects or processes should be arranged reasonably during the construction process. Strengthen drainage in rainy season construction to prevent foundation pit collapse.
2. Investigate and master the rainy season data in detail, and take temporary protective measures during construction.
3. Reserve of main materials and machines for construction preparation in rainy season.
4, the rainy season construction education for employees.
5. The design and construction of temporary works should fully consider the rainproof requirements, and do a good job in the drainage system of the service road. Arrange special personnel for maintenance, patrol regularly before and after the rain, and set up obvious traffic signs.
6, in addition to timely grasp the daily weather conditions, but also with the local meteorological department to sign a forecast agreement, the local meteorological department regularly provide ten-day and monthly weather forecasts, and make reasonable construction arrangements accordingly.
7, the rain period construction in the excavation of foundation pit, slope stability should be paid attention to. If necessary, you can slow down the slope or set up supports. At the same time, an earth embankment or ditch should be built around the outside of the pit to prevent the inflow of surface water. Check the slope, support and earth embankment frequently, and handle the problems in time when found.
4.6 quality standards
(1) Ensure that the foundation soil of column foundation, foundation pit and site of the project must meet the design requirements, and no disturbance is allowed.
(2) The foundation soil excavation of column foundation, foundation pit and site of general projects must meet the requirements of specifications.
4.7 finished product protection
(1) is used to locate standard piles, axis guide piles, standard leveling points, gantry plates, etc. No collision is allowed during digging and earthmoving, and no collision is allowed on the gantry plate. And should often measure and check whether its plane position, horizontal elevation and slope meet the design requirements. Positioning standard piles and standard leveling points shall be regularly re-measured and checked for correctness.
(2) During earthwork excavation, settlement and deformation of adjacent existing buildings or structures, roads and pipelines should be prevented. When necessary, we should take protective measures in consultation with the design unit or the construction unit, and observe the settlement or displacement during the construction.
(3) If cultural relics or ancient tombs are found during the construction, they should be properly protected and reported to the local authorities in time for treatment before the construction can continue. If permanent survey stakes or long-term observation points set by geological and seismic departments are found, they should be protected.
Chapter V Safety Assurance System
5. 1 excavation measures
1. When excavating a foundation pit with underground water level, measures should be taken to reduce the underground water level according to local engineering geological data. Generally, it should be lowered to 0.5m below the excavation face before excavation.
2. The roads where construction machinery comes into play should be checked in advance, and preparations should be made for reinforcement or widening when necessary.
3. The selection of earth-moving machinery should be determined according to the topography and working conditions of the construction area, the type and thickness of soil, the total engineering quantity and the construction period, so as to give full play to the efficiency of construction machinery.
4. The layout of operation routes in the construction area shall be determined according to the work scale, mechanical performance, transportation distance and terrain fluctuation in the operation area.
5. In the parts where mechanical construction cannot be carried out, manually trim the slope and clean it up.
6. When digging a large foundation pit with an excavator, it should be dug downwards in layers according to the longitudinal branches of the slope line, but the middle part of each layer should be slightly higher than the sides to prevent water accumulation.
7. Backhoe and pull shovel have two construction methods:
1) end excavation method: the excavator drives backwards from the pit bottom to excavate. Dump trucks are arranged on both sides of the excavator to load soil.
2) Side excavation method: the excavator moves the dump truck along one side of the pit, and the other side is filled with soil.
8. The scraper construction method is used for excavation.
9. When the excavator moves along the excavation edge, the width of the machine from the upper edge of the slope should not be less than 1/2 of the depth of the foundation pit. When the excavation depth exceeds 5m, it shall be determined according to the professional construction scheme.
10. In the process of excavation, the state of the groove wall and slope should be checked at any time. When the depth is greater than 1.5m, the foundation pit should be well supported according to the soil conditions to prevent collapse.
1 1. When excavating the foundation pit, it shall not be lower than the design elevation. If you can't dig to the design foundation elevation accurately, you can leave a layer of soil above the design elevation without digging, and then dig manually after leveling.
12. Temporary soil layer: when general scrapers and excavators dig about 20cm, backhoe, front shovel and pull shovel should be used to dig about 30cm.
13. Earthwork that can't be excavated by mechanical construction should be excavated at any time with the help of manpower, and it should be hauled to the excavated place by mechanical hand for timely excavation.
14. Help repair and bottom cleaning. At the edge of the tank 50cm away from the design elevation of the tank bottom, find out the horizontal line, nail the Xiao Mu branch pipe, and then manually dig out the temporary soil layer. At the same time, both ends of the axis (center line) will pull the pile through the line (with small wire or lead wire), check the size from the groove edge, and determine the groove width standard. Trim the groove edge in this way, and finally remove the earthwork at the bottom of the groove. Quality inspection and acceptance shall be carried out after the tank bottom is repaired and leveled.
15. When the earthwork for foundation pit excavation is piled up in the site, enough good soil must be reserved for backfilling; Excess earthwork should be transported away at one time to avoid secondary handling.
5.2 Safety protection measures
A. after foundation pit excavation, the whole line shall be trimmed manually. Dressing requires that the protruding earth wheel left after mechanical excavation should be leveled along the slope direction to prevent air drying, cracking and falling off.
B. Manually remove earthwork and particles within the range of 1.5m from the upper mouth of the foundation pit to the ditch side.
C. Set a fence within 2m from the pit edge along the periphery of the foundation pit, and the height of the fence is1.5m.
D. Hang safety warning signs and safety warning ropes at obvious positions along the fence.
E. The pit shall be patrolled by designated personnel, and the patrol personnel shall be on duty 24 hours a day.
F, set up a red signal warning light along the ditch fence at night.
G. When the pit bottom is constructed in rainy days and sun exposure days, the pit walls on both sides shall be covered with colored strips, so as to avoid foundation pit collapse caused by continuous infiltration of rain and pit wall loosening and sliding caused by sun exposure.
5.3 Safety guarantee measures
(1) The upper and lower grooves must be covered by sidewalks and safety ladders. . The distance between safety ladders should not be greater than 50 mm. (2) Before dismantling the support, the buildings, structures and pit walls on both sides of the foundation pit should be inspected for safety, and the detailed implementation rules and safety measures for dismantling the support should be formulated.
(3) When excavating earthwork mechanically, slope and soil shall be piled according to the requirements of safety technical disclosure, and excavation is strictly prohibited. The track or tire shall keep a distance of 1.5m or more from the foundation pit.
(4) Check the excavator before operation, make sure that there are no obstacles and other personnel within the movement range of the boom and bucket, and sound the horn as a warning before operation.
(5) A guardrail of not less than 1.5m should be erected around the foundation pit, warning lights should be set up, and special personnel should be assigned to patrol.
(6) When piling with artificial holes, the pile height shall not exceed 1.5m, and the distance from the edge of the orifice shall not be less than 1m, and the pile shall not cover other facilities.
(7) When picking up the bottom of artificial foundation pit, the horizontal spacing between two people shall not be less than 2m, and the vertical spacing shall not be less than 3m.
(8) Before hoisting, safety disclosure shall be made to crane drivers and commanders.
(9) When installing the tower crane, the crane should be parked at a safe distance, not near the foundation pit, and obey the command and arrangement of the full-time security officer.
(10) When installing the tower crane, send someone to check whether the pit around the parking lot is loose or cracked.
(1 1) Due to the deep manual excavation of the hole pile foundation, it is necessary to assign special personnel to command and pay attention to the safety of the basement operators.
5.4 Monitoring measures
1. A safety team is composed of full-time safety officers led by the project manager. The team members are from the operators of each construction bid, and one person is transferred from each construction bid.
2. Team members should be trained in various safety regulations.
3. Team members should take the lead in improving the safety of the construction site.
4. During the construction of their respective blocks, team members should first check all kinds of unsafe factors before construction, so as to achieve "prevention first and safe construction".
5. When excavating deep foundation pit, it is necessary to check the settlement and displacement of adjacent buildings, roads and surrounding environment for observation.
6. When working in a deep foundation pit, it is necessary to check whether the soil on the trench walls on both sides of the foundation pit is loose and cracked, and also check whether the surrounding environment of the trench has surface water flowing into the foundation pit, causing landslides.
7. When pruning manually, check whether there are underground facilities (cables, pipes, etc.). ).
5.5 Emergency Plan
1) Every manager should be trained in safety knowledge so as to be able to cope with the emergency on the construction site.
2) When a safety accident occurs, the general manager and site management personnel of the company should arrive at the scene at the first time and handle the safety accident in time.
2) Arrange a car at the construction site to deal with emergencies at the construction site.
3) In case of a major safety accident, contact the local public security department, hospital, resident troops and government in time and send people to participate in the rescue.
5) Safety accidents must be reported and cannot be concealed.
5.6 rescue measures
1. First time notice 120 ambulance.
People who are seriously injured should be sent to the hospital in time.
3, the construction site to prepare some rescue medical drugs.
5.7 Environmental protection measures
With the improvement of people's living standards, the status of environmental protection is becoming more and more important. In order to respond to the call of the state and Chengdu to do a good job in environmental protection and meet the relevant requirements of the owner, efforts are made to do a good job in environmental protection according to the characteristics of this project.
(1) Make use of the time after weekly safety study to increase the publicity of environmental protection laws and knowledge and improve the environmental awareness of all employees.
(2) Solutions for various pollution sources:
1, to prevent noise pollution
1) Arrange the construction time reasonably, and do not use noisy construction machinery such as vibrating hammer at night. Noisy construction is prohibited after ten o'clock in the evening.
2) Check and maintain the construction machinery frequently to ensure that the equipment is always in good condition and avoid noise disturbing people and polluting the surrounding environment.
2, to prevent the pollution of mud and silt
1) The excavated spoil must be removed within 24 hours to avoid site accumulation, and the remaining mud shall be removed by bulk carrier.
2) Go through all kinds of formalities in strict accordance with the regulations of Chengdu on sludge discharge and put them in the designated place side by side.
3) The earthwork piled on site shall be covered; Earth-moving vehicles entering social roads should be closed for flushing.
4) Earthwork transportation roads are often watered to prevent dust.
3, to prevent construction and domestic sewage pollution
1) to prevent sewage from flowing out of the construction site and polluting the surrounding environment. Sewage in the living area should be precipitated and separated from slag to avoid blocking the drainage pipe network.
2) The wheels of vehicles entering and leaving in rainy days must be cleaned to prevent the wheels from coming out of the mud and polluting the surrounding environment.
(three) to prevent dust and waste gas pollution
1. Put a sack 50m at the entrance and exit of Guangdu Avenue to prevent the particles unearthed from the tire from entering the social road.
2, set up a full-time cleaning team, regularly clean the channel, guardrail, and sprinkle water on the channel to prevent dust flying.
3, mobile construction machinery to do a good job of maintenance, especially the exhaust emission detection, try to reduce exhaust pollution.