Based On Upper Bound Analysis Of Bearing Capacity Of Building Foundation Includes Hole

The development of urban underground space caused many buildings must be in the hole on the foundation of construction. In the design of foundation, the most important thing is to determine the bearing capacity of foundation design value, only determine the bearing capacity of the foundation design value, can provide the basis for the design of building foundation after. The traditional method of sub grade bearing capacity, problem of hole in the ground, there are many difficulties. The maximum limit analysis method is an effective way to solve this problem.Based on the rigid block limit analysis upper bound method the research buildings contain hole of foundation bearing capacity, and combined with numerical simulation to verify the rationality of this method, the main research contents are as follows:(1)First of all, this paper expounds the basic principle of limit analysis upper bound method. Rigid slider on the limit analysis are discussed Limit method, the characteristic and applicability of failure mode and the construction of virtual displacement method are discussed in this paper, finally constructed including the failure mode of circular tunnel cavern foundation, the ultimate bearing capacity of the foundation to solve by the upper-bound method principle.(2)This paper discusses the different width, cavern buried depth, the basis of the properties of rock mass of the holes the ultimate bearing capacity of the influence.(3)Use the finite difference software, a numerical simulation of the foundation of buildings including holes contrast circular tunnel excavation before and after the foundation of the stress field of difference; after the foundation of analysis of circular tunnel excavation release stress and the plastic zone.(4)Simulation under different position of uniformly distributed load bearing capacity of foundation, and with maximum limit analysis method is used to calculate limit comparison results.