The Improved Contact-Interaction Force Element Model And Its Application In Geotechnical Engineering

Discontinuity is the most essential characteristics of geo-materials and interaction system of rock or/and soil and structures. Hence, a very important issue is to rationally evaluate and simulate mechanical behavior including deformation and failure process of such systems subjected to loading in a rational way.Prof. Luan Maotian and Dr. Li Yong of Dalian University of Technology advance discontinuous deformation computational mechanics model to solve the problem of discontinuity in geo-materials. The model is established based on the generalized finite elements and contact force elements and absorbs merits of numerical manifold method. It is a numerical method which is used on discontinuity. The present method can not only fulfill static and dynamic coupling analysis simultaneously, but also can gradually simulate complex nonlinear process of multi-body systems such as deformations and stresses and contact stresses and relative movements along contact interfaces.For complex multi-body interaction systems, the key problem of the systems is the problem of contact. In the discontinuous deformation computational mechanics model, the non-smooth feature will be manifested and jump of contact stresses frequently occurs since the contact stresses along the contact surface are assumed to vary linearly. In order to properly display the contact behavior of interfaces during loading, an improved contact-interaction force element is given by virtue of a nonlinear function of relative distance with high-order differential continuity. In the modified model, the nonlinear distribution of contact stresses along the contact surface is duly taken into consideration. For a given benchmark problem, numerical analysis is conducted and verification of rationality and eifectiveness of the proposed method is made by comparing the computed results with the solution given by Abaqus which is an universal finite element software for structural analysis.Finally, the presented method is successfully applied to the theoretically important and practically significant problem of interaction of soil and foundation in geotechnical engineering. Reasonable results and significant conclusions are obtained which may offer valuable references for practical engineering.In summary, based on the linear contact force element model of discontinuous deformation computational mechanics model, no-linear contact force element model is presented. Both fundamental theory and numerical procedures are given. With numerical analysis the method in the paper is rational and effective.