Three-dimensional Numerical Simulation Analysis On Interactive Of Superstructure And Underground Cavern

With the rapid development of economic construction in our country,andthe land resources is scare very much in the city，the problem is outstanding thatbuilting high-rise buildings on top of the underground cavern of undergroundengineering or construct the underground buildings such as the subway underthe surface buildings. If the traditional calculating method is without regard tothe interaction of foundation with caverns and superstructure, the result will beunreasonable and cause a big discrepancy between calculation and reality.Superstructure, base with underground cavern and foundation are an organicwhole which influence and connect each other. The interaction of foundationand superstructure is a key and major problem in many projects, and haspractical application value to study it. This text is on the background of realenbineering case of Outpatient Building collapse in Shanxi Province, and usingAnsys to establish The whole model of Tree-dimensional finite element, andthen use the model to study the interaction of foundation and superstructure.The main contents and conclusion are showing as following:(1) The interaction theory of base with underground cavern, superstructureand foundation has been described,meanwhile it has been expositioned thereinforcement method of underground cavern and stress mechanism. (2) For the finite element method and the software Ansys are described, atsame time it has been described the soil constitutive model.(3) The basic information of project and underground cavern are introduced,to understand the engineering properties of ground soil, and to obtain the basicparameter that computational analysis required. While making a detailedanalysis of the accident in project, and to get the basic reason for the collapse ofsuperstructure. Combined with specific examples of projects,and to use ANSYSto establish the overall three-dimensional finite element model to analyze theinteraction of foundation with caverns and superstructure.(4) With the increase of the upper load, settlement of foundation soilincreases, does not meet the requirements, but also to the unstable undergroundcavern development, and cavern foundation needs reinforcement.(5) Simulation analysis of the impact that changes the superstructurestiffness to the presence of underground cavern foundation, and drawing cavernexists for related impacts soil, the exist of a cavern to reduce the soil settlement,but also increases the range of soil settlement, and increasing the influence ofthe upper structure to the surrounding buildings. Also simulating the depth ofunderground caverns and depth changes of soil reinforcement to influencing tothe cavern foundation, and to come to a reasonable depth of soil reinforcement is7m.(6) Summarzing the main content and conclusions of this paper, andproposing the future reasearch directions.