| Discontinuous constructions such as joints, weak interlayers, and faults are prevalent in the foundation, which causes great difficulty for establishing FEM-model and conducting FEM analysis. It is therefore an important and hard problem to be solved during computation. It is actually one of the solutions to contact problems. That is the basic point from which this paper selects the theme. So establishing 3D FEM-contact-model for gravity dam and putting it into actual analysis on deep anti-sliding stability is the main topic the paper explains about.In this paper, the establishment of 3D FEM-contact model is based on elastoplasticity FEM theory and contact FEM related theory on ANSYS operating platform. The core of this model is using solid element to simulate elastoplasticity deformation of faultage and using contact element to simulate the interface of faultage and rock, and so, realizing the problems coupling of elastoplasticity and contact.In discussion on the actual application of contact analysis to ANSYS, the paper focuses its discussion on the selection of contact element, configuration of true constants, and the simplified treatment of friction matters. Besides, it also discusses what the selection of true constants for FTOLN and FKN will affect the analysis on complicated foundation system that contains weak interlayers, defines the values for FTOLN and FKN.Based on the established 3D FEM-contact-model, it is analyzed that the deep anti-sliding stability and deformation for the whole 51# and 52# sections at Yunfeng Slotted Gravity Dam. By the results of analysis and comparison, it proves sufficiently that this FEM-contact-model for gravity dam is accurate, rational and credible.Furtherly, in allusion to the absence of design standard in FEM, basing subency coefficient and reliability idea, it puts forward subentry coefficiet FEM method. This method is more rational than tradional safety factor method in the judging of degree of sagety of structure. |
PDF Full Text Request