CN-121992831-A - Quick installation and reconstruction construction method for deep buried pipeline in saturated water powder sand stratum in near water area

Abstract

The invention relates to the technical field of pipeline construction, in particular to a method for quickly installing and reforming a near-water saturated water powder sand stratum deep buried pipeline, which comprises the following steps of S1, determining the size of a working pit, the size of a platform, the size of a steel sleeve box and the model of Larson steel sheet piles; the method comprises the steps of S2, carrying out square lowering treatment on shallow layer ground surface soil, S3, adopting a primary Larson steel sheet pile to carry out closed support, S4, arranging primary pipe wells around the primary Larson steel sheet pile to carry out dewatering and decompression, S5, carrying out primary working pit excavation, S6, carrying out secondary Larson steel sheet pile construction, S7, adopting C20 concrete as a hardening treatment on an operation platform, S8, carrying out dewatering by using a diode well, S9, uniformly applying a plurality of steel pipe wells in the secondary working pit, S10, lowering the secondary working pit to the bottom elevation of an accident pipe, hanging the steel sleeve box into the secondary working pit, embedding the accident pipe into a notch of the steel sleeve box, and S11 pipe hoisting and welding. The invention has the technical effects of quick excavation at the pipeline accident position and quick construction speed.

Inventors

• LI JIA
• FENG XINXUE
• ZHANG GUOZHUANG
• GAO QIANG
• JIANG XIAOBO
• DONG SHULIN

Assignees

• 中国二十二冶集团有限公司

Dates

Publication Date

20260508

Application Date

20260330

Claims (5)

1. 1. A construction method for quickly installing and reforming a near-water area saturated water powder sand stratum deep buried pipeline is characterized by comprising the following steps: S1, determining the size of a working pit, the size of a platform, the size of a steel sleeve box (3) and the type of Larson steel sheet piles step by step from inside to outside according to engineering and hydrogeology, the position, depth and working face requirements of an accident pipeline (12), and carrying out working condition simulation, stress analysis and calculation on the working pit by a computer software technology to verify the local and overall stability of a structure; s2, carrying out square-falling treatment on shallow layer ground surface soil according to soil property conditions and surrounding environments, and carrying out slope-falling excavation by adopting a backhoe excavator after determining the square-falling depth; S3, calculating and determining the excavation depth of the primary working pit according to engineering geology and hydrologic conditions, and adopting a primary Larson steel sheet pile (1) for closed support; S4, arranging primary pipe wells (5) around the primary Larson steel sheet pile (1) to carry out precipitation and decompression; S5, excavating a primary working pit, and simultaneously excavating an enclosing purlin and a steel support (4) of a steel sheet pile along with the excavation; s6, after the primary working pit is dug to a preset elevation, retracting the primary Larson steel sheet pile (1) inwards by four meters, and constructing the secondary Larson steel sheet pile (2) by taking the primary working pit as an operation platform; s7, the operation platform adopts C20 concrete for hardening treatment, the hardening belt is also used as a concrete supporting belt (9) of the primary steel sheet pile (1), and meanwhile, a shaping mould is adopted to reserve the position of the diode well (6); s8, performing dewatering by using a diode well (6), wherein the depth of the bottom of the diode well (6) exceeds the depth of a weak water permeable pink clay layer below a quicksand layer by not less than two meters; S9, after the concrete of the concrete supporting belt (9) reaches a certain strength, uniformly applying a plurality of steel pipe wells (8) in the secondary working pit, burying the bottoms of the steel pipe wells (8) into a sand flowing layer, discharging the sand layer in a suction mode at a distance of one meter from the bottoms of the sand flowing layers, and sinking an upper-layer powdery clay layer by self weight until the upper-layer powdery clay layer is lowered to the elevation of an accident pipeline (12), wherein the steel pipe shafts are disassembled along with lowering in the process, and meanwhile, building purlins and steel supports (4) of the secondary steel sheet piles (2); S10, the secondary working pit is lowered to the bottom elevation of an accident pipeline (12), a steel sleeve box (3) is lifted into the secondary working pit, the accident pipeline (12) is embedded into a notch (14) of the steel sleeve box (3), four corners of the steel sleeve box (3) are uniformly pressed by a vibrating hammer, the lower opening of the steel sleeve box (3) is cut into a weak permeable powdery clay layer to be not less than 1.5 m, the top of the accident pipeline (12) is required to prop against the notch (14), meanwhile, soil mass with the depth range of 0.5m at the bottom of the accident pipeline (12) is manually removed, a sand bag and cotton cloth are adopted to seal the notch (14), underground water is continuously pumped and discharged inside and outside an additional water pump (7), and the water level is controlled below 0.5m at the bottom of the pipe; S11, welding one end of a connecting pipeline (11) with an elbow on the ground, arranging a hanging point at the other end, vertically hanging the connecting pipeline (11) into a steel sleeve box (3) by using an automobile crane, and carrying out butt welding treatment with an accident pipeline (12), wherein the crane always keeps a transferring posture without loosening a hanging hook in the process; S12, after the pipeline welding, the test and the joint repairing are finished, the working pit is filled, after the working pit is filled into the upper end of the connecting pipeline (11), a crane hook can be used for constructing an upper bent pipe of the connecting pipeline (11).
2. 2. The construction method for quickly installing and reforming the deep buried pipeline in the saturated water powder sand stratum in the near water area according to claim 1, wherein the bottom depth of the primary pipe well (5) exceeds the weak water powder clay layer below the quicksand layer by no less than two meters.
3. 3. The construction method for quickly installing and reforming the deep buried pipeline in the saturated water powder sand stratum in the near water area is characterized in that the top finishing elevation of the secondary Larson steel sheet pile (2) exceeds the surface of an operation platform by 700mm.
4. 4. The construction method for quickly installing and reforming the near-water area saturated water powder sand stratum deep buried pipeline is characterized in that the steel sleeve box (3) is formed by welding steel plates and section steel, no bottom and no cover are arranged, and the middle part of one side of the steel sleeve box (3) embedded into an accident pipeline (12) is cut into a semicircular gate-type notch (14).
5. 5. The construction method for quickly installing and reforming the near-water area saturated water powder sand stratum deep buried pipeline according to claim 1 is characterized in that the central axes of the surrounding purlin of the primary Larson steel sheet pile (1) and the steel support (4) are coincident with the thickness central line of the concrete support belt (9).

Description

Quick installation and reconstruction construction method for deep buried pipeline in saturated water powder sand stratum in near water area Technical Field The invention relates to the technical field of pipeline construction, in particular to a method for quickly installing and reforming a pipeline deeply buried in a saturated water powder sand stratum in a near water area. Background Along with the acceleration of urban progress in China, the energy source conveying demand continuously grows, a large number of long-distance pipelines shuttle in complicated sections such as cities, villages, mountainous areas and rivers, directional drilling is favored as a common construction method for traversing construction, but when geological and hydrologic conditions are poor, disturbance by external factors or construction operation is improper, accidents such as hole collapse, unhooking, pipeline or drill rod fracture and the like are often caused by pipeline back-towing, particularly in saturated water powder sand stratum in a near-water area, wide and thick powder and fine sand layers are buried underground, and the water powder sand stratum is often clamped between watertight layers and contains a large amount of saturated groundwater, so that a flowing sand layer is formed, the stratum has very strong thixotropic property and water permeability, and pipeline burial depths are tens of meters or even tens of meters, so that pipeline excavation repairing possibility is basically zero, and great difficulties and challenges are brought to pipeline reconstruction and repairing work. The conventional method has two methods, namely, abandoning an accident section, carrying out secondary punching and towing pipe construction again at an alternative position, and modifying a pipeline route to carry out open cut construction, so that huge economic cost is required. In summary, the existing method has the problems of single method, high manufacturing cost, high cost, slow speed and long period. Disclosure of Invention In order to solve the problems in the prior art, the invention provides a construction method for rapidly digging, reconstructing and repairing a pipeline accident position. The invention provides a construction method for quickly installing and reforming a near-water area saturated water powder sand stratum deep buried pipeline, which adopts the following technical scheme: a construction method for quickly installing and reforming a near-water area saturated water powder sand stratum deep buried pipeline comprises the following steps: S1, determining the size of a working pit, the size of a platform, the size of a steel sleeve box and the type of Larson steel sheet piles step by step from inside to outside according to engineering and hydrogeology, accident pipeline positions, depths and working face requirements, and performing working pit working condition simulation, stress analysis and calculation through a computer software technology to verify the local and overall stability of a structure; s2, carrying out square-falling treatment on shallow layer ground surface soil according to soil property conditions and surrounding environments, and carrying out slope-falling excavation by adopting a backhoe excavator after determining the square-falling depth; S3, calculating and determining the excavation depth of the primary working pit according to engineering geology and hydrologic conditions, and adopting a primary Larson steel sheet pile for closed support; S4, setting primary pipe wells around the primary Larson steel sheet piles to carry out precipitation and decompression; S5, excavating a primary working pit, and simultaneously excavating an enclosing purlin and a steel support of a steel sheet pile along with the excavation; s6, after the primary working pit is dug to a preset elevation, retracting the primary Larson steel sheet pile inwards by four meters, and performing secondary Larson steel sheet pile construction by taking the primary Larson steel sheet pile as an operation platform; S7, the operation platform adopts C20 concrete for hardening treatment, the hardening belt is also used as a concrete supporting belt of the primary steel sheet pile, and meanwhile, a shaping mould is adopted to reserve the position of the diode well; s8, a diode well is manufactured for dewatering, and the depth of the bottom of the diode well exceeds the depth of a weak permeable silty clay layer below a quicksand layer by not less than two meters; S9, after the concrete supporting belt reaches a certain strength, uniformly manufacturing a plurality of steel pipe wells in the secondary working pit, burying the bottom of the steel pipe wells into a sand flowing layer, discharging the sand layer by pumping from the bottom of the sand flowing layer, and sinking an upper powdery clay layer by self weight until the concrete supporting belt reaches the elevation of an accident pipeline, wherein the steel pipe shafts ar