Simulation Analysis On The Mechanics Properties Of Super-Long Group Piles Foundation

Along with large-span bridges and high buildings getting the development in China, alarge number of super-long group piles are applicated in engineering, The stress of thesuper-long group piles foundation is complex, its mechanical properties still lag behind theengineering practice of research. Therefore, studying on mechanical properties of thesuper-long group piles foundation analysis for understanding the load-bearing mechanism hasimportant significance.Thesis is on the basis of existing pile foundation theory, mainly for the following work:simple theoretical calculation method of super-long single pile are introduced, and the sheardisplacement method is deduced in the homogeneous soil and stratified soil load-settlementformula, and compared with the existing formula for load transfer method. For soil soft andhardening effect on the pile top settlement, using Midas/GTS finite element software formodeling, along the pile length distribution is analyzed the influence of different depth soilstrength of pile foundation. Considering the elastic modulus ratio of pile to differenceinfluence on pile foundation, pile top settlement and pile axial force are analyzed.Based on the Shan Xian extra-large bridge of zheng-xi passenger line super-long grouppiles foundation, in accordance with the specifications at home and abroad, the foundationsettlement are manual calculation and GTS with finite element calculation results, this papercompares and analyzes the relevant conclusions. Considering the super-long group pilesbearing system, the caps-pile-soil stress system, thickness of pile caps on pile groupfoundation has important influence. For the super-long group pile caps of different thicknessof modeling analysis, mainly discuss the caps settlement, stress, pile top reaction, pile endresistance and side friction properties.Considering the different on the bottom of the pile caps is localized to the influence ofthe stress system, also setting model and analysis of the stress reaction with the pile top andpile caps of subsoil intensity changing rule. In order to verify the reliability and feasibility ofGTS finite element software, combining with Dong Ying Yellow River bridge of the indoormodel test and GTS finite element software is adopted to indoor has carried on the numericalcalculation model, and compared with the test results analysis, and further confirms thefeasibility of GTS finite element software. Finally in this paper, the pile group effect ofsuper-long group piles foundation are analyzed, and analyses the influence law from thequantity, to the follow-up engineering design optimization provide certain reference.