1, facilities and personnel are ready to approach. Work includes installation of construction equipment, temporary organization and dispatching of a group of hydropower lines. It is expected to be completed in three days.
Well point dewatering construction. It takes 18 days to complete the installation of each category of light well points. In order to finish the project as soon as possible, two teams can be arranged at the same time. When excavating the nail wall, you can install semi-finished products at the well point and start pumping water.
3. Soil nailing wall construction. The construction side of soil nailing wall supports each other, and the layers and parts support each other. After excavation, support should be started immediately, and it cannot be stopped. According to the characteristics of soil nailing wall, organizational equipment and talent team construction, the construction period of soil nailing wall is tentatively set at 25 days.
4. Earthwork excavation. During the construction of soil nailing wall, the earthwork in the cabinet will be excavated. After the construction progress is completed, it is expected that the centralized excavation project will be completed within one week.
5. Resign. It takes two days for the equipment personnel to quit. "
Summary platoon is an invisible factor and needs effective duration, which is estimated to take 50 days.
Construction preparation work
Construction preparation, construction site preparation, technical preparation and raw materials, machinery and equipment ready.
(1) Site preparation
1, before the equipment enters the construction site for investigation, know the site conditions, geological conditions and surrounding environment in detail. After the signing of the contract, the preparatory work will immediately enter the preparatory stage, organize the implementation of personnel, contact materials, and check the mechanical integrity of the station in mechanical work.
2. The location and maximum available amount of water and electricity, and the water and electricity are supplied to the construction site. The on-site power supply is not less than 100KW, and the water supply is not less than 70 cubic meters/day;
Please assist the owner to find underground obstacles and corresponding pipelines, and determine the position of surrounding piles to ensure that the enclosure will not affect the construction piles.
4. According to the site conditions, choose cement silo, mixing station and cement silo with an area of about 50 square meters;
According to the construction progress, the unit that realizes the material supplier will organize and plan in advance to formulate the method of the main material (cement) of the material supplier and the on-site sampling inspection procedure of the material, and recheck the main raw materials of the strength cement for three days according to the regulations, and put them into use only after they are stable and qualified.
6. Arrange work, union accommodation and other logistics unit tools.
(2), technical preparation
Learn the technology of atlas organization, and the management personnel are fully familiar with drawings, construction specifications and technical documents. Understand the design intent and define the quality requirements;
2, graphics test, and do a good job of the blue prints.the design;
Do a good job in the technical, safe and civilized construction test of the team;
4. Organize safety technical disclosure meeting. pay off
(c) hand over the site to a good positioning benchmark, and recheck the visa work with Party A's unit; At the same time, the reporter, elevation, coordinates and datum points of construction, organization technology, safety and integration before the handover of the general contractor are required.
2. Release the positioning control points of the retaining structure, and strive for a better position according to the layout of the positioning line and the excavation line.
& gt (1) Construction machinery is equipped with 8 sets of construction machinery and personnel.
Since its establishment, our company has been engaged in all kinds of enclosure engineering and pile foundation engineering for a long time. In the process of building enclosure construction, according to different geological conditions, we have accumulated rich quality control measures. The deepening of underground garage is considered in the design partly because of the construction experience, and the construction of garage is mainly considered in the construction planning. Tentative selection of envelope construction: complete sets of soil nailing wall equipment, 18 sets of well point dewatering equipment (considering the actual situation of the project, the layout of the construction site, the electricity and water consumption of the construction party, the equipment and the integrity rate of the construction capacity. Only the garage part) adopts backhoe excavator to excavate soil nailing wall during earthwork excavation.
The main construction equipment of PZ-5B shotcrete machine adopts soil nailing wall construction, and the transportation distance is 200 meters. 9M3 air compressor is used for power transmission, UBJ 1.8 squeezing pump is used for cement grouting, and the theoretical horizontal conveying distance is 100m. The anchor pipe is inserted into the pneumatic power supply of the 9M3 air compressor of JB 12-C photoelastic impact drilling rig.
Name, model and specification of equipment unit of power (KW)
9M3 air compressor WY-9/7-Y Phase II
PZ -5B 5.5 shotcrete machine
Grouting Machine UBJ 1.8 2.2 Table 1
Impact drilling rig JB 12-C unit 2
Luoyang shovel 80mm to 2
Faucet HJ-200 2.2 1
BX-350/400 welding machine 7.5
Bar straightener cutter head L30-400 2.2 2.2 1
List of soil nailing wall equipment (single equipment) BR />2. List of light well point dewatering equipment
Type and specification of equipment Power (KW) Units
100 mm long perforating gun root 1
18
Mud pump vacuum pump 2S-185 5.5 85 7.5 1
3. Earthwork excavation equipment
Crawler 1.5m3 excavators, earthwork car 15t or 20t dump trucks 10. (two) staffing methods, the combination of the company and its employees
Construction personnel, the specific personnel are as follows:
Complete equipment of soil nailing wall
The work content of the industry is that migrant workers, managers and skilled workers weld anchor pipes, make welded steel pipes and fix them.
Specific operation of shotcrete gun by shotcrete worker 1 surface
Grouting operation of grouting anchor pipe
Electrical and electrical equipment management and tracking all types of laying.
Auxiliary work 10 anchor pipe excavation and other auxiliary work
*** 16
Well point dewatering (single team) management, logistics construction management and material management < BR/ Work contents of affairs.
Electrical equipment management and electrical wiring.
Plumber 2 Stamping Assistant
Assist workers to complete the continuous drawing of punching well points ***8
cut
Description of the number of seats for personnel and machinery
Earthwork construction safety officer is responsible for 1
The excavator can drive 24 workers as an independent.
Earth-moving truck driver 10 20 Machinery 2
Other migrant workers
Because the construction industry and the construction process, construction workers can change industries at the same time, and the actual number of construction workers will follow the plan.
Nine, well point precipitation
(A) the purpose of precipitation
According to the construction requirements of this project, the purpose of foundation pit excavation and foundation slab structure dewatering is:
1, add pit and pit bottom in dry soil, so as to lift it into reinforced foundation and soil, so as to improve the resistance of pit soil and reduce the uplift and deformation of pit bottom retaining structure.
2. It is beneficial to the stability of slope and the prevention of longitudinal landslide.
3. The underground water level of the foundation pit is low and the construction is convenient. Excavators and workers are in the pit.
The precipitation in the preliminary layout will be based on the foundation, and the number of structural wells and well points in the layout will be adjusted if necessary.
Shell-opening construction, drainage works in the soil and underground foundation pit enclosure, reduce the groundwater level, to ensure the smooth progress of dry foundation pit construction. Determine the perimeter and area of a general pit? The experience of the effective pumping range of a single well, the empirical value is the characteristics of the phreatic aquifer and the plane shape of the foundation pit. Generally, the effective rainfall radius of light precipitation well point is 6-7 meters.
(2), well point
1, precipitation equipment
The diameter of resource manager used in ZBL-9-60 or 2S- 185 vacuum light well point system, and the length of branch pipe at 100 well point is 4.0m and 6.0m, and the diameter of each well point is 48, 30-40, and the length of filter pipe is 0.8m.. Commonly used PVC or rubber coated steel hoses are connected and sealed with adhesive tape.
2, well point hit
The advantages of light well point device and equipment, combined with professional construction experience, our company has arranged dewatering well points in the actual situation of foundation pit slope, which has played an anti-seepage role. Considering that in order to excavate earthwork smoothly, temporary dewatering wells are arranged in the pit. Underground garage *** 18 sets of well point precipitation.
Better settings, strive to start the excavation of foundation pit before 10, and start the pre-precipitation and precipitation work for 7 days from the earthwork excavation. Specially set up the purchase time, according to the schedule requirements, due to the site conditions or schedule requirements, as well as the click rate in the process of foundation pit excavation.
It is better to set branch pipelines and directly carry out high-pressure well washing at selected locations with high-pressure water jet. High pressure water must keep the water pressure at 0.8? 1.2MPa line, the pipe diameter of water supply pipe at the construction site is not less than 100 mm, which can be solved by using reclaimed water.
For all kinds of projects with smooth infrastructure construction, the sinking distance between the oil well pipe and each well point and the well point manifold should be less than the bottom of the filter pipe under1.5m..
3. Construction technology
The construction process is as follows:
Resource manager of pay-off ditch raft? Punched immersed tube? Fill in the sand connectivity resource manager to install the pumping unit to test pumping.
4. Construction procedures and quality requirements
(1) The excavation line of the first edition issued by the construction party of the building structure, the well point position of the excavation line under the enclosure, the trench with the excavation depth of 1m and the width of 1m should be like this. When a large amount of water is drained, the punching hole diameter should be controlled first. Generally, the aperture should not be greater than 80mm and the depth should be greater than 0.5m, and the distance between filter tubes with a depth of 1.5m is higher than the bottom.
At the same time, the drilling depth of 0.5m filter tube should stay for a period of time, so as to ensure that the muddy water overflows into the hole, and quickly inject about 60kg of gravel, and then put it into the well tube. The gap above 0.5- 1m of natural gravel ground for irrigation should be filled with clay to prevent air leakage. Then, in the excavation process of gradually sealing down, each well point will make the sand-filled pipe and hole wall sink.
(2) If leakage is found, the "dead well" shall be dealt with immediately.
(3) After all oil well pipes are distributed, the resource manager should be connected immediately to start the unit trial pumping. Comprehensively check the quality of pipe joints, and ensure the construction quality by running the pumping machinery under the condition of well water. For point connection, the connection nozzle of PVC or rubber and metal hose should be coated with waterproof material, waterproof material and common grease. Cork or waterproof cover, used to seal both ends of the resource manager. sewage
(4) It is normal to pump muddy mud. After a week, the water should be very clear. Groundwater pumping pit spacing 10 meter, or repeated circulation of water affects precipitation.
(5) Open (dark) drains must be set at the bottom of the excavation pit.
Technical measures
According to theoretical calculation, the project adopts light vacuum well point, the effective working range is one atmosphere, and the precipitation is about 8 meters. The pointer of the pressure gauge can reach the starting point of 0.6MPa, and can maintain precipitation with an effective radius of about 6.0 meters. The working radius of the dewatering device is about 7 meters, which is arc-shaped. Therefore, in order to ensure the dewatering effect, the excavator should be pre-pumped for 7- 10 days.
2. In the case that the water level in the pit for monitoring the precipitation outside the pit must change, it must be ensured that the change of the water level outside the pit will not be affected, and the precipitation construction will be carried out.
On the basis of monitoring, the excavation unit must coordinate the settlement observation of surrounding buildings, roads and pipelines, generally once every 12 hours, and make settlement records. If each measurement must exceed 10mm, emergency measures should be taken to prevent settlement.
Item (d)
Filter tube construction requirements for the diameter and quantity of well point dewatering punching holes must be equipped with engineering soil; For drilling, the hole diameter shall be no less than 80mm, the sand filling weight shall be 150kg, and the grain size of yellow sand shall be no less than 1.5? 3mm connecting pipe must ensure no water leakage, and it is forbidden to use damaged main power supply and hose, and the damaged and leaking pipes should be replaced; Restart after shutdown should not exceed 48 hours to avoid the phenomenon of "dead pipe".
In the process of foundation pit excavation, the non-collision points and connecting hoses of excavators should be replaced in time if they are damaged.
During the excavation of the foundation pit at the protection well point, water should be pumped continuously, and the plug should be pulled out after the foundation slab construction is completed. In the process of foundation pit excavation of temporary dewatering well, shearing and drawing
Bottom of foundation pit. The phenomenon of sand gushing and piping is large, so the precipitation at two well points should be considered.
(5) precipitation and running notes
1, part of the precipitation system, should be closely connected, no water leakage, air leakage, water leakage phenomenon.
2. During the precipitation operation, a 24-hour on-site duty system shall be implemented, and special personnel shall be assigned to take care of all units.
3. Under the condition of open ditch drainage preparation, do a good job in foundation pit drainage in time to prevent deep foundation pit excavation.
4. During the precipitation operation stage, check the working state of the vacuum pump frequently, and adjust the pump and maintain it in time if any abnormality is found.
5. During the precipitation operation stage, it should be ensured that in the case of power failure, the relevant units should inform the precipitation construction workers two hours in advance, so as to take timely measures to ensure the precipitation effect.
Ten earthwork excavation
(1) Organizational construction
The rectangular circumference of the local garage pit is about 627 meters.
Because the retaining structure of foundation pit is supported by soil nailing wall, the main work of earthwork excavation and soil nailing wall is soil nailing wall construction until the soil nailing wall construction is completed, excavation and excavation.
1, organized and implemented the specific requirements for familiarizing with website construction and party building, specifically responsible for the coordination between construction personnel and construction, soil nailing support, familiarity with surrounding road conditions, and arrangement of construction vehicle passages;
2. Organize the matching of earthmoving equipment in this project, and arrange some excavators and loaders according to the requirements of construction progress;
3. The spoil ground should be implemented before excavation. It takes three days to prepare for unloading soil, and the cleaning staff need to realize the construction access point of unloading soil, the unloading report and the organizational view of abandoning soil.
4. External coordination of buildings. Declare the route of vehicles on the road declared by the muck disposal procedure, coordinate the relationship between traffic police and patrol officers on the construction site, and make the construction unimpeded. Manned vehicles and unified command and coordination;
5. Construction cleaning measures. General excavator drivers, under the construction load of three-sided compaction, when the floating dust on the surface of the car is scattered in the soil, should clean the side of the car in time, clean the soil with the tires of the gantry car in vehicle engineering, and wash the road in time. On Dongmen Road, a woven bag was laid at the entrance of earthwork vehicles, and it was commanded by one person.
(II) Construction scheme for medium-sized and excavators
Party A and the supervision unit shall give a written notice or oral notice three days in advance, and the excavation sequence of excavators and general contractors needs to do a good job in foundation lofting and SD pile preparation.
2, the general contractor's preparations:
① Confirmation of determining ground and underground obstacles and removing all obstacles;
(2) determine the internal distribution, pipeline excavation, pipeline protection; ?
(3) Site roads and site entrances:
According to the actual situation of the project site, the hardened masonry door will be excavated at the construction site of Longwu Road and the earthwork approach road at the entrance of the site, and earthwork car will be arranged to wash the pipelines on both sides.
(4) Construction waste residue in road hardening pit;
(5) After positioning and lofting of earthwork excavation, release the structural axis.
⑥ When excavating, leave 20cm thick soil after excavation, organize the structural construction personnel immediately after artificial excavation, pour the cushion layer, and send out roof excavation and slope forming. Control elevation
3, earthwork excavation construction process:
Its own characteristics, when earthwork excavation, the use of independent groups, multi-level interchange assembly line, so that the project makes full use of space and time, to ensure the smooth progress of excavation and retaining support.
The construction of building envelope needs to be completed in accordance with the general principles of daily envelope construction, excavation and soil nailing wall excavation, and the limited assets and liabilities are over-excavated.
The project is long and narrow, and the excavation should be divided into two long-side plane sections, each of which should not exceed 30 meters in length.
The excavated soil nailing wall is usually the central island, which is excavated along the foundation pit, and the soil nailing wall is constructed to excavate the foundation trench.
Construction waste and other hard slag in the pit should be paved with temporary gradual evacuation passages, or with a width greater than 6m, and tamped with excavators.
The excavation began, and the soil retained by the excavation mouth began to be excavated in the pit. In the process of construction, the retaining excavator is used to excavate the soil nailing wall. The width of the construction groove of soil nailing wall of foundation pit is about 6-7 meters. According to the requirements of soil nailing wall construction, the angle of pit bottom slope should not be less than 1 13. According to the zoning requirements, the length of each excavation should not exceed 30 meters. (The excavation of the first floor can be carried out continuously, not in sections).
The excavation depth of the first layer is designed to be 20 cm, and the excavation of each layer is controlled at one meter until the end. Excavation will affect the surface soil nailing wall and steel anchor head.
During the construction of soil nailing wall.
After the completion of soil nailing wall construction, vehicles will be concentrated and excavators will be deployed to carry out 24-hour uninterrupted construction in a large area. Dig.
4, excavator control
(1), designated persons shall be responsible for the loading of the excavated earthwork, and the site shall be clean and the traffic shall be smooth. dig
(2) In the process of soil nailing wall construction, limited excavation is required to complete a lot of work, the depth of soil nailing wall can be controlled every day, and the overbreak pit bottom can be raised.
(3) Earthwork shall be excavated to the design elevation, the elevation of shares shall be manually measured and controlled, and then it shall be led to the excavator to control the piling of bamboo piles.
(4) Finally, the basement surface is excavated with earthwork with a thickness of about 200mm. ..
(3), quality and safety measures
Excavate the potential safety hazards that are easy to occur in the process, and formulate corresponding measures to protect yourself.
2. It is forbidden for anyone to enter the working scope of the excavator. The commander of the excavator, except the special forces? In this case, you should stop the operation and re-enter the internal command that is not allowed to enter the working range of the excavator. When it is necessary to enter the working range of the excavator, the operation should be stopped and re-entered.
3. Drivers and operators of all types of machinery and vehicles must be certified and tested before and after work.
4. It is inevitable that earthwork excavation will not be over-excavated, which does lead to over-excavation. The application procedure should be completed as soon as possible, and the website cannot be backfilled after completion.
5. The 200mm thick earthwork left at the bottom of the pit is excavated manually and mechanically, which lays a foundation for preventing or reducing interference.
6. The design elevation of the excavation area should be watered immediately without any interference.
7. Strengthen the monitoring in the process of soil nailing wall excavation, feedback the rebound of soil in time, and take effective measures to prevent accidents.
8, the provisions of the drainage blind ditch collecting well on the soil surface, in order to eliminate water in the pit, should be cleaned in time during the construction process, in order to prevent congestion.
9. Pay attention to avoid obstacles when digging cables and gas pipelines to prevent accidents.
Cleaning measures
Conscientiously implement the relevant provisions of the municipal party committee and municipal government, make unified planning and rational layout, and create a civilized construction environment.
1, car wash tank at vehicle entrance and exit, centralized treatment of car wash wastewater and unified discharge.
2. The car wash tank on the right hand side of the door of the earth-moving vehicle is next to the car shovel, and the wheels, wheels and body are filled with water and washed with a high-pressure water gun.
3. Make a final inspection of the vehicle to prevent the vehicle guard plate from loosening and avoid the earth pollution caused by drip irrigation.
4. The entrance road is covered with earthwork woven bags, carpets and other fabrics. When the wheels are tired, the sewage drips and leaks, and the cleaning cloth pad belt is often replaced. /& gt； 5. When the excavator is on site, there will be someone who is responsible for road cleaning and cleaning up the earth and other sundries dropped by the truck.
On the 6th, after the earthwork excavation, immediately flush the surrounding roads, so as not to pollute the environment.
XI soil nailing wall construction
(1) construction preparation
Technicians and constructors should be familiar with the requirements of design drawings and relevant regulations, the preparations for building a well-off society in an all-round way, the surrounding pipelines and buildings, and the geological reports, paying special attention to the distribution of soil, the physical and mechanical parameters of each layer of soil and the integrity of machinery and equipment. All engineering materials should be inspected, and the development and construction sequence should be coordinated with the excavator unit. Mobilize and educate in order to carry out the preliminary work of construction.
(2), soil nailing construction
In soil nailing construction, the disclosure method of construction information can determine the supporting parameters (length and density) of soil nailing in construction according to the actual situation, and can change the construction scheme. In case of an accident, contact the designer in time and make corresponding measures. When encountering an underground obstacle, we must try to adjust the hole to avoid the obstacle and ensure a safe pit. The most important thing is the excavation and earthwork of soil nailing wall construction.
Please refer to the foundation pit drawings for soil nailing parameters.
1, construction technology
After the construction of soil nailing wall is completed, please refer to the following contents when the pit line is used to repair the excavation slope, make holes, grout and spray concrete support.
/& gt； Next layer system anchor
Actinomyces. what's up Digging? Maintenance of slopes? Is the gunite placed in a fixed place? Grouting? Net? Foundation pit monitoring
The surrounding attic
Pay off and supervise the surrounding foundation? Construction can be started only after inspection. Excavate the surrounding earthwork before re-setting out for inspection.
3. Earthwork excavation and soil nailing support
In order to ensure the safety of soil nailing wall foundation construction, foundation pit excavation must be carried out in layers along the soil nailing support section, overbreak and excavator. During the excavation process,
Soil nailing wall is divided into two stages: the first stage
The progress of foundation pit excavation and soil nailing wall construction, and the coordination of earthwork excavation before the cooperation of all parties shall be held to determine the progress of earthwork excavation of all parties. During the excavation of soil nailing wall, after the completion of soil nailing wall construction within the excavation scope, the daily workload shall not exceed. The height of the excavation face shall conform to the vertical spacing between the building and the soil nailing support, and the upper mouth of the ditch shall be 6-7m wide.
The design of soil nailing support is 20 cm above sea level. 1 m, the excavation of each floor is controlled. After excavation, the whole pit plane should be divided, and the length of each excavation section is about 30 meters. From the beginning of excavation, the excavation of the second floor must be started, and each support should be supported for enough time to control the progress of earthwork excavation supported by the soil nailing wall at the bottom of the last floor of the foundation pit.
The next layer of soil nailing support can only be started after the soil nailing grouting is completed for more than 24 hours, 12 hours, and the curing strength surface concrete pouring is completed. The excavation process and the formation of soil nailing wall construction cycle. The excavation of excavator does not affect the wall and anchor head of the network.
The last layer of soil nailing wall construction completed the second stage of large-scale foundation pit excavation and earthwork transportation.
Earthwork excavation should be divided into plane areas and vertically layered, and overbreak is not allowed. The general principle is that excavators should obey the orders of soil nailing to support the soil nailing wall under construction.
For the working face formed after earthwork excavation, soil nailing should be completed within 48 hours.