Study On Mechanical Characteristics Of Composite Support Structure With Curved Spaced Row Of Piles And Soil Nail Wall

Due to the continuous acceleration of the pace of urbanization in China,many high-rise buildings in many cities are also continuously being built,or some underground spaces are effectively used.Therefore,some important theories or some practical contents of the current foundation pit support technology It is becoming more and more important,and the support technology used before now does not meet the current requirements.In this context,taking the deep foundation pit support as an example,from the perspective of optimizing the structure type and improving the efficiency of the structure,a high-efficiency foundation pit support structure with arc-shaped spacing rows of piles and soil nail walls is given.In order to be able to effectively study the supporting system proposed this time,this article has effectively compared some conventional pile-soil-nailed wall supporting structures,and sorted out some important functions of piles and soil-nailed walls in the supporting system.Mechanism and the failure mode of soil arch shear under soil arching effect.This research also carried out specific testing research on the reduced-size arc-shaped spaced pile-soil-nail wall composite supporting foundation pit model,and obtained the main conclusions about the progress.In terms of finite element analysis,ABAQUS is used to carry out targeted research and discussion on the force and deformation of the original-size arc-shaped spaced pile-soil-nailed wall supporting structure corresponding to the reduced-size model test.In order to efficiently verify part of the mechanical theory of the supporting structure given in this paper,this paper carried out the test of the deep foundation pit structure model of the composite supporting structure of arc-shaped spaced piles and soil nail wall,and analyzed the stress of the soil,and analyzed the Some bending moment values,strain values,soil-nailed wall axial forces,etc.involved in the piles,during the test process,the working conditions in the loading test are carried out in stages,and the relevant stable test values ??are recorded,and then analyzed and supported.The change trend of the related internal force of the protective structure,this test can be obtained: the arc-shaped interval pile-soil nail wall composite supporting structure has good bending performance and resistance,and can produce excellent supporting effects.Using the ABAQUS finite element analysis software,through indoor scale reduction model tests,a finite element model of the arc-shaped spaced pile-soil-nail wall supporting foundation pit was established,and the foundation pit excavation conditions were simulated through the setting of analysis steps.Focusing on soil deformation,pile body strain,bending moment,and soil-nailed wall axial force,through combing the relevant forces of the supporting structure proposed this time,the following three conclusions can be obtained from the analysis:(1)During the horizontal loading test,The related deformation of the composite supporting structure of arc-shaped spaced piles-soil nail wall can show the relevant division of"bulging"in the horizontal direction,and the maximum horizontal displacement appears in the lower part of the pit wall surface layer Area.(2)For foundation pits supported by arc-shaped spaced rows of piles-soil-nailed walls,the internal force of the piles is higher than that of arc-shaped spaced rows of piles-connected beams because of the soil nailing wall bearing the load of the soil between the piles.The pits are significantly and effectively reduced;(3)The changes in the axial force of the soil-nailed wall at different locations are similar,and the force of the soil-nailed wall has a unique maximum along the length direction,and the axial force is small at both ends and large in the middle..