Analysis On Pile-soil Interaction Of High-rise Building Considering Contact Effect

Along with the speeding up of urbanization process of our country, high buildings rapid developed. And pile is the preferred method of foundation treatment. As a result, the interaction between pile and soil is being more and more paid attention to. There are several urgent problems must to be solved in the research of the interaction between foundation and ground. Especially, the simulation of the pile-soil interface condition such as slippage and fracturation is one of the hotspot and difficulty. This paper, on the basic summarizing predecessors' researching results, does some research on the finite element calculating methods in the pile-soil interaction in the case of no thickness contact element, including the choosing of constitutive model , parameter of contact element and their influence on pile-soil interaction, etc. Tasks that this paper mainly finishes are as follow:1. Summarize the researching status of contact problems, and introduce several frequently used contact element and their constitutive models. Also conclude the mechanism and calculating methods of the contact element in finite element.2. Set up a friction pile finite element calculation model, compare the calculating result of the finite element with the actual measurement, to validate that the contact element of zero thickness can do better qualitative simulations in the condition that the breakage is on the foundation-ground interface, and prove the feasibility of simulation sliding failure between pile and soil with contact element of zero thickness.3. Taking advantage of the large-scale- finite -element -analysis software ANSYS, set up a simulation model of pile-soil interaction, and use it to research on the parameter of the contact element. Thus obtain the general rules of parameter value adopting, and the influence on the rule of load transfer, settlement and ultimate bearing capacity. At the same time, discuss the influence that the qualities of pile and soil put on settlement and ultimate bearing capacity of single pile.4. Research on the realization of the initial crustal stress field and its influence on the pile-soil interaction. Compare the result putting the initial crustal stress field into account with without in the subject of distribution of the friction on side of the pile, load transfer, settlement, and ultimate bearing capacity, etc.. Give the conclusion that the influence which the initial crustal stress field puts on the pile-soil interaction cannot be ignored. At the same time, compare the calculating result which putting the interaction between pile and soil into account with without.