Study On Anti-sloughing And Auxiliary Trench Construction Technology Of Pre-precipitation Under Diaphragm Wall Crossing Through Silty Sand Layer With Freeble Confined Water

Based on the civil construction of TJ2108 label in N ingbo metro,for using triaxial stirring pile reinforcement the groove wall while the diaphragm wall crossing micro artesian water and sand layer, there are high costs, long construction period, relatively large impacts on the environment and other serious defects, this paper conducted a system study on the auxiliary technology research while diaphragm wall trench construction crossing the micro artesian water and sand layer.First, take a test of conventional means, The result as compara tive sample of late-stage trial.Then take a test of trench construction with Pre-precipitation,using the results to make a Comparative analysis of conventional means. O n this basis, make a on-site optimization test, improving Precipitation system deployment and operation method from the economic point of view.By the methods of combining on-site field test and numerical simulation analysis, through the relationship of tank wall stability and Pre-precipitation Forward calculus expected technical parameters a nd guiding Field test. O n the other hand, according to the experimental data, derived reasonable indicator in the opposite direction.By the research of the Diaphragm wall with Pre-precipitation before excavation to keep the groove walls stabilization, developed a new technology and methods named “Auxiliary technology with Pre-precipitation and preventing collapse of The diaphragm wall trench construction crossing the micro artesian water and sand layer”, and applied to the actual project. The core contents includes the layout of precipitation wells, beginning and ending time of precipitation, precipitation depth, layers, etc. This paper can provide reference for similar projects...