High-water-content soft soil dewatering excavation integral trenching pipeline construction method

Abstract

The invention relates to a high-water-content soft soil dewatering excavation integral trenching pipeline construction method. The method comprises the following steps that 1) a cofferdam dewatering structure is constructed; 2) water in gunny bag cofferdams is pumped out, the surface of a riverbed is exposed, and temporary drainage blind ditches are constructed on the riverbed surfaces on the twosides of a trench to be excavated; 3) a steel sheet pile enclosure is inserted on the surface of the riverbed on the inner sides of the gunny bag cofferdams; 4) ramp slides are arranged on the gunny bag cofferdams on the two sides; 5) after the trench in the steel sheet pile enclosure is dug to a specified elevation, the adjustable easily-disassembled support is disassembled; 6) a material box isplaced on a filler moving and conveying frame; 7) a pipeline is placed on a pipeline moving and conveying frame; and 8) the material box slides to the top surface of the trench by using the filler moving and conveying frame. The method has the beneficial effects that the pipeline is lengthened on the pipeline moving and conveying frame, slides to the top face of the trench through the slides and then is integrally lifted through a sliding lifting support; the problem of transportation of the pipeline in the cofferdam is solved; and meanwhile, the pipeline integrally descends to the trench , and the sealing performance of a pipeline joint is improved.

Description

technical field [0001] The invention relates to the construction of high-water-content soft soil pipelines in river gushing areas, in particular to a construction method for excavating integrated trench pipelines in high-water-content soft soil for rainfall excavation. Background technique [0002] During the construction of pipelines in soft soil with high water content in river gushing areas, due to the high water level of the river, the natural water level during the construction period is higher than the elevation of the top surface of the trench, so it is often used to fill cofferdams on both sides of the trench, and then carry out Excavation and pipeline trenching construction operations; however, due to the high groundwater level, it still has a greater impact on trench excavation and pipeline trenching operations. Since the riverbed is soft soil with high water content and low bearing capacity, the filled cofferdams are deformed or collapsed. Large-scale constructio...

AI Technical Summary

Problems solved by technology

[0002] During the construction of pipelines in soft soil with high water content in river gushing areas, due to the high water level of the river, the natural water level during the construction period is higher than the elevation of the top surface of the trench, so it is often used to fill cofferdams on both sides of the trench, and then carry out Excavation and pipeline trenching construction operations; however, due to the high groundwater level, it still has a greater impact on trench excavation and pipeline trenching operations

Since the river bed is soft soil with high water content, the bearing capacity is low, resulting in deformation or collapse of the filled cofferdam

Large-scale construction machinery cannot enter the construction site, so the pipeline cannot be spliced ​​as a whole before being placed in the trench.

Due to the limited working space in the groove, the sealing performance of the joints and the axis accuracy of the pipeline cannot be effectively guaranteed, which affects the construction quality of the pipeline, and the splicing operation in the pipeline groove increases the risk of the operators and reduces the safety.

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