关键词: 接触问题, 虚功原理, 有限元, 岩土工程, 界面

Abstract: Almost all the problems of geotechnical engineering have to deal with the interaction between geotechnical media and the structures. Therefore, the simulation of interface plays an important role in the computation. At present, usually the Goodman joint element, Desai thin-layer element etc. are employed to simulate the interface, which is convenient in use but not so reasonable. In contrast, taking as a contact problem, the principal mechanical characters of the interfaces can be reflected as follows: (1) the contact interface is of shear strength which implies that a generic pair of contact points on the interface will displace coincidentally if the tangential force at this point has not reached the limit resistance, else, relative slide between the points will occur along the tangential direction; (2) no matter the relative slide occurs or not, the contact bodies cannot penetrate each other in any wise. A finite element approach to solve deformable body-rigid body contact problems is developed. The finite element formulae are constructed on the basis of the virtual work principle. Also, the techniques to solve the elastoplastic contact problem are given. The examples concerning pressure distribution beneath rigid strip footing and the lateral earth pressure on retaining wall are solved successfully, which verifies the validity of this method.

Key words: contact problem, virtual work principle, finite element, geotechnical engineering, interface