Deformation Analysis And Optimization Of Pile-internally Supported Support Structure

China is now in a period of rapid development,various buildings are springing up,and every city can see places under construction,among which excavation and support of foundation pits are the foundation of building construction.Due to the development of construction machinery and construction technology,the size of foundation pit excavation is getting bigger and bigger nowadays,however,bigger and deeper foundation pits also bring bigger safety hazards.In the process of foundation excavation and support,controlling the deformation of the enclosure structure and ground settlement is a prerequisite to ensure construction safety.We use the finite element software MIDAS GTS NX to simulate the excavation and support process of the foundation pit,analyze the influence of the depth of encasement pile and the diameter of the encasement pile on the deformation and surface settlement of the encasement structure,and explore the solution of foundation pit support with lower cost under the premise of ensuring the safety.Using finite element software to simulate the excavation and support of the foundation pit,analyze the influence of the diameter of the enclosure pile,the spacing of the enclosure pile,the embedded depth of the enclosure pile,the size of the crown beam,the stiffness of the internal support and the spacing of the internal support on the deformation of the enclosure structure and the surface settlement.After the inflection point,the horizontal displacement curve of the enclosure structure and the surface settlement curve will gradually level off if the pile diameter continues to increase;the inflection point of the horizontal displacement curve of the enclosure structure and the surface settlement curve is 1.5m,and the horizontal displacement curve of the enclosure structure and the surface settlement curve will gradually"steepen" if the pile spacing continues to increase;the horizontal displacement value of the enclosure structure and the surface settlement value are in the safe range if the embedded depth is 8.6m.The size of crown beam has less influence on the deformation and surface settlement of the enclosure structure;when the spacing of steel support is 3.5m and the spacing of concrete support is 8m,it has the best effect on controlling the deformation and surface settlement of the enclosure structure;when the size of steel support is 500mm diameter steel pipe support with 16mm wall thickness and the cross-sectional size of concrete support is 0.8m X 0.8m,it has the best effect on controlling the deformation and surface settlement of the enclosure structure.m ×0.8m,it is the inflection point of the horizontal displacement curve and surface settlement curve of the enclosure structure,and when the internal support stiffness continues to increase,the horizontal displacement curve and surface settlement curve of the enclosure structure gradually tends to level off.Through the conclusion of numerical simulation analysis,the optimized support scheme was summarized,and the optimized support scheme was implemented in the engineering case,and then by calculating the stability of the foundation pit,it was concluded that the optimized support scheme was reasonable,and in terms of economy,the optimized support scheme saved about 284,000 RMB than the original support scheme.Figure[48]Table[18]Reference[58]...