The general distance between them is 120~ 150, with working wells in the middle and receiving wells on both sides. One-way pipe jacking of pipe jacking working well is a rectangular working well, and the receiving well is basically circular; Multi-directional pipe jacking adopts circular pipe jacking working well.
Long-distance pipe jacking can also be used, depending on the engineering needs.
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Construction scheme of pipe jacking working well and receiving well
Construction scheme of pipe jacking working well and receiving well
catalogue
1, project overview? 1
2. Preparation before construction? three
3. Compilation basis? three
4. Analysis of website construction characteristics? four
5, construction deployment and resource planning 4
6. Timetable? five
7. Construction process? five
8, the main construction methods and quality requirements 5
9. Quality assurance measures? seven
10, civilized construction measures 9
1 1, main safety technical measures 10
12, detection 14
13, emergency rescue plan 14
14 with chart
Schedule 1: mechanical equipment demand plan
Attached Figure 1: Flowchart of Manual Well Drilling
1. Project overview
1. 1 This project is the first-phase pipe network project of Huizhou Huzhen Sewage Treatment Plant, which is the main sewage pipe of Hu Yong Town, collecting the sewage from residents and road gravity along the way to the intermediate pumping station. The total length is about 7.8km, in which W01-W06 is designed with φ400 high-density polyethylene double-wall corrugated pipe, and the ring stiffness is SN8. The inner side of this section of soil is close to the retaining wall, and the outer side is the river channel, which is about 0.25km long. W06—W30 is designed with φ500 high-density polyethylene double-wall corrugated pipe (HDPE) with ring stiffness SN8. The local position of the outer river channel was buried by large excavation, and the length was about 1. 1 km. W30—W42 is designed with φ800 reinforced concrete pipe jacking (level 3) and pipe jacking construction. Part of this section passes through residential roads, and the rest are rural roads, with a length of about 0.68 km. W42—W47 is designed with φ800 high-density polyethylene double-wall corrugated pipe (HDPE), and the ring stiffness is SN8. This section of large excavation is buried in the natural slope of the river, with a length of about 0.29 km. Among them, W47- lifting pump house is designed with φ800 reinforced concrete special pipe jacking (Grade III) for pipe jacking construction. This section is located in the countryside, beside the highway, with a length of about 0.93 km and two sections *. The working well is φ 7500 round well with a wall thickness of 500mm；; The receiving well is a φ 4500 round well with a wall thickness of 350 mm, and the excavation depth of the top tube well is 8 ~ 12m. Before excavation, use φ 550 @ 400 double-row high-pressure jet grouting pile to seal around the well.
1.2 This project is designed by Guangdong Zhongtian Municipal Engineering Design Co., Ltd., and the geotechnical investigation report is provided by Shantou Yuedong Engineering Survey Institute. Shenzhen Ganquan Construction Supervision Co., Ltd. is responsible for the project supervision and Huiyang Branch of Heyuan Municipal Engineering Corporation is responsible for the construction.
1.3 geological conditions
This survey found that within the drilling control depth, the site stratum is mainly composed of plain fill, miscellaneous fill, silty clay, silty sand and medium sand. The stratum of the site and its physical and mechanical properties are described in layers as follows:
1.3. 1 artificial plain fill (Q4ml): yellowish brown, loose, slightly wet, mainly silty clay, with uneven soil quality, which is recent.
Stacked filler, containing a small amount of ore. The layer thickness is 0.8 ~ 6.5m, the buried depth of the top layer is 0.0m, and the elevation of the top layer is14.70-19.67m .. ZK1~ zk4 * * 4 borehole distribution.
1.3.2, alluvium (Qatar)
2 1)( 1) Qal(○: yellowish brown, plastic ~ hard plastic, smooth twist, medium toughness, dry strength,
Alluvial origin; The layer thickness is 2.70 ~12.50m; The buried depth of the top floor is 0.8 ~ 2. 1m, and the elevation of the top floor is12.60 ~15.62 m. ..
For the soil sample in this layer 1 group, the standard penetration test was conducted for 4 times, with 7 ~ 10 blow, and the modified blow count was 6.50 ~ 8.60 blow.
Strike. This layer is distributed in borehole ZK 1 ~ ZK2 * * *.
22)(2) Silt Qal(○: yellowish brown, wet, slightly to moderately dense, rough surface, obvious shaking response, toughness and dryness.
Low strength, uniform soil, locally mixed with silty clay; The layer thickness is 0.60 ~ 3.80m; The buried depth of the roof is 6.8 ~ 9.3m The elevation of the top is 3.82 ~ 5.30m.
Two groups of soil samples were taken from this layer, and the standard penetration test was carried out for three times, with the blow count of 7 ~ 14 and the modified blow count of 5.80 ~ 1 1.0. This layer is found in borehole ZK2 ~ ZK4 * * * distributed in three boreholes.
23)(3) Silty sand Qal(○: grayish yellow, saturated, loose to medium dense, mainly distributed in timely and feldspar, with impure sand.
Silty soil; The layer thickness is 3.00 ~ 5.30m; The buried depth of the top floor is1.70 ~10.30m. The elevation of the top floor is11.32 ~14.97m. ..
The standard penetration test of this layer was conducted twice, and the blow count was 6 ~ 18, and the revised blow count was 5.60 ~ 14.0. This layer is found in borehole ZK 1 and ZK3 ~ ZK4 * * * distribution.
24)(4)Qal medium sand (○: grayish white, saturated, slightly dense, mainly distributed in timely and feldspar, with impure sand and mixed with silty sand.
Thin layer; Poor grading; Layer thickness1.50m; ; The buried depth of the top floor is14.0m. The elevation of the top floor is 0.7m
1.4 groundwater situation
There is groundwater in all boreholes within the depth controlled by the survey, and groundwater is mainly groundwater, supplemented by atmospheric precipitation.
There are abundant groundwater in the 22nd floor, silty soil ○ 23rd floor and medium sand ○ 24th floor, which are the main influences. Fill ① layer, silt ○
Aquifer. Fill, silt and sand layers have good water permeability and strong water-abundance, which are strongly permeable layers; Silty clay is a weakly permeable layer.
2. Preparation before construction
2. 1 Jointly with relevant departments, the blue prints.the design was conducted, and various technical requirements in the construction process were defined.
2.2 Before the commencement of construction, the construction unit is required to provide relevant information about underground pipelines of buildings (structures) within 30 meters outside the building line, so that the construction unit can have a deeper understanding of the surrounding buildings. According to the site conditions, the construction unit should send people to inspect the surrounding underground pipelines, structures, building foundations and superstructure, and record them for future reference.
2.3 Before construction, the construction unit should do a good job of three links and one leveling, and the construction unit should do a good job in the layout and installation of drainage and construction electricity plane lines in the site. Pay-off accurately according to the construction drawings, release the center line of the well location and the well diameter, carefully check the technology, and go through the visa formalities with the relevant departments before excavating the earthwork of the shaft.
2.4 Before construction, do a good job of testing steel, cement, sand and stone to determine the mix proportion of construction concrete. All kinds of main materials should have factory certificate and test report.
2.5 Carry out physical examination for all construction personnel, and carry out three-level safety education, safety technology and sub-project implementation after passing the physical examination.
Work quality and technical disclosure, and do a good job in visa procedures. Safety technology management should be implemented ideologically, organizationally and by measures.
2.6 Before construction, installation inspection and acceptance shall be carried out for the equipment and all electrical and wiring that enter the site. Equipment and electrical appliances that do not meet the requirements of safety regulations must be rectified, and can be put into use only after they meet the requirements through inspection.
2.7 Reasonable arrangement of on-site living and production facilities, clear division of labor and management personnel, and implementation of post responsibilities.
2.8 Drainage construction should be done well before the top tube well construction to ensure normal well digging.
3. Compilation basis
3. 1 construction drawing of sewage treatment plant in Hu Yong Town, Huiyang District, Huizhou City (20 10. 1 1)
3.2 Geotechnical investigation report of the whole pipe network (Shantou Yuedong Engineering Investigation Institute)
3.3 Technical Specification for Building Pile Foundation (JGJ 94-2008)
3.4 Unified Standard for Acceptance of Construction Quality of Building Engineering (GB50300-200 1)
3.5 Code for Construction and Acceptance of Building Foundation (GB50202-2002)
3.6 Code for Acceptance of Construction Quality of Concrete Structure Engineering (GB50204-2002)
3.7 Code for Welding and Acceptance of Reinforcement (JGJ18-2003);
3.8 Standard for Test Methods of Welded Joints of Reinforcement (JGJ/T27-2001);
3.9 Standard for Inspection and Evaluation of Concrete Strength (GB/T 50107-2010);
3. 10 building construction safety inspection standard (JGJ 59-99)
3. 1 1 Technical Specification for Safety of Temporary Electricity Use in Construction Site (JGJ46-2005)
3. 12 Relevant documents of provinces and cities
4, site construction characteristics analysis
4. 1 The construction site is narrow, so it must be carefully organized, reasonably arranged and strictly managed to complete the task with a high sense of responsibility.
4.2 The proposed top tube well is close to adjacent houses and shops, and corresponding measures must be taken during construction to ensure that the normal operation of shops is not affected.
4.3 The groundwater in the site belongs to phreatic water, and the aquifer within the excavation scope is mainly silty sand.
5. Construction deployment and resource planning
5. 1 construction deployment
5. 1. 1 plan 12 people dig holes in three teams, with 4 people in each group. Full excavation, a section of shaft wall should be completed every day, the normal soil layer is 0.95m, and the bad soil layer (silt or quicksand layer) is 0.30~0.45m m.
5. 1.2 3 people will be cleared and transported. In the process of construction, each type of work should adjust or increase manpower at any time according to the progress needs.
5.2 Resource Plan
5.2. 1 human resources
Site management personnel: 5 persons.
operator
Monitor: 3 people
Skilled workers: 12
Welder: 3 persons
Electrician: 1 person
infrastructure
In order to ensure the construction quality of this project, the project department will allocate temporary offices, install temporary power supply and water supply and drainage systems for construction, and equip suitable mechanical equipment (see attached table 1 mechanical equipment demand plan).
6. Schedule
The planned construction period of this project is 50 days.
7. Construction process flow
See attached figure 1 for the construction process of the reverse digging well in this project.
8. Main engineering construction methods and quality requirements
8. 1 high pressure jet grouting pile construction
8. 1. 1 jet grouting pile construction sequence:
1), the pilot hole drilling rig is in place to pilot the hole.
2) Unscrew the nozzle to the designed pile bottom elevation, and put the jet grouting pile machine in place.
3), while lifting, jet grouting to the designed pile top elevation.
4) Lift and clean the drilling tool.
5) Move the machine to the next hole position.