Study On The Applied Of Pile-chemical Churning Anchor Cable In Deep Foundation Pit Support Engineering Of The Yellow River Flood Area

Along with the rapid development of urban construction In the last ten years, the problemof narrow space is growing more seriously, this makes the utilization ratio of undergroundspace becomes higher and higher, and then foundation pit engineering has been generallyaccepted. Now foundation pit engineering appears some new features, such as excavationdeeper, large scale, complex environment, requires high, set a still higher demand on theapplication of supporting theory, structure design, construction scheme. Pile-anchorsupporting as a kind of combined support system has been applied widely, it control smalldeformation, application flexible, convenient construction, mature design methods, it providea good option to the foundation pit which excavation space small, complex environment，surrounding underground pipeline densely covered.A deep foundation pit in Henan Province locate in the Yellow River Flood Area, the mainsoil are clay and silty clay, the underground water level was higher, the compressibility of soilis higher, so usual single support system cannot satisfy the deformation requirements, choicestep-slope&pile-chemical churning anchor cable&waterproof curtain combined supportsystem, obtained good result. Because spray protecting stiffness of slope is small andwaterproof curtain belongs to flexible pile, it mainly depend on pile anchor resistance load.This paper combined with the actual situation of engineering, research the applied on deepfoundation pile-anchor supporting structure, summarize theoretical result, analysis workingmechanism, the change law of foundation pit stress and strain. The main working contentsincluding:1、Analysis the anchor cable stress develop depend on the result of Calculation andmonitoring and Simulated, verification the application effect of chemical churning anchorcable.2、Based on monitoring data, comparison analysis with calculation and simulated,further study the deformation law of support structure, and the compatible deformationbetween pile and chemical churning anchor cable.3、Choice pile-chemical churning anchor cable support system, analysis some stabilityinfluencing factors in foundation pit excavation.Research based on monitoring data, obtained some conclusion of pile-chemical churninganchor cable support: 1、choice step-slope&pile-chemical churning anchor cable&waterproof curtaincombined support system in the deep foundation pit of Yellow River Flood Area, the supportapplication effect is good, provide reference for deep foundation pit support in the same soilmass conditions.2、The effect of chemical churning anchor cable application in soft silty clay is good,effective exertion of anchoring force, effectively reduce the foundation pit movement;pre-stressed Anchor interact with soil after stretch locking, at the same time pile and anchorcable coordination work, reach equilibrium stabilization condition.3、Get the support structure and deep foundation pit deformation law, because ofstep-slope, the top of pile around foundation pit load develop, the center of deep soilmovement shift down, and the max movement appear on the middle of the foundation pit.