Mechanism Research About High-rise Construction Pile-raft Foundation Together Action And Optimized Design

About the near 20 years, have yielded the substantial result based on the finite element analysis superstructure and the ground foundation common fundamental research. But affects the theory achievement together in the project practice application obvious lag; "The subsidence control compound pile foundation" design theory proposing is affects the theory together in the soft soil area with the application in the actual project application, but this kind of design mentality and the method to the region, the pile, as well as superstructure aspect and so on layer all have the strict limit. As a result of the foundation soil distribution and the composition infinite variety, the earth this construction relations which proposed also has been different at present, then subsided between the predicted value and the actual value had the very big difference, like this caused this theory to be restricted in the promoted application; In recent years the domestic and foreign scholars also proposed in the cloth pile way "In Strong Outside Weak", "Outside Strong In weak" two entirely different cloths piles way, also all applies in the project practice, the practice and the theoretical analysis indicated the two all have the certain good and bad points under some kind of specific condition.This article first in the predecessor about in the pile raft foundation settlement computation foundation, proposed the consideration soil body non-linearity revision lamination method of summation subsidence computational method; Then uses the numerical analysis the method, established the pile soil, the pile raft foundation and the foundation soil separately using the ANSYS finite element analysis software, the superstructure pile raft foundation and the ground local guerillas synergy analysis model, Has analyzed the stress character and the mutual influence which each part affects together; Finally proposed in this analysis foundation proposed one pile raft foundation optimized method—"sinks controls levelling" the design method. Paper main work and research results:a. The contrast has analyzed the present pile raft foundation settlementcomputational method, the Duncan ground model introduction subsidence computation in, and the consideration foundation soil three directions stresses influence, proposed in this foundation "the revision lamination method of summation" the subsidence computational methodb. Uses large-scale finite element analysis software ANSYS to establish three dimensional single pile analysis model, the two-dimensional group pile analysis model separately and the superstructure pile raft foundation entire finite element analysis model, discussed the pile length, the pile diameter, the pile number, the cloth pile way, raft board thickness and the earth module to the influence which affected together.c. Proposed "sinks controls levelling" the pile raft foundation design method. And has produced the design procedure.