The finite-element method is finding increasing use in the structural analysis of pavements. In pavement analysis, very deep finite-element meshes need to be used to satisfactorily model the infinitely deep subgrade layer. Programs require large amounts of computer memory and computational time. A scheme is developed in this paper to overcome the computational burden imposed by the requirement of a deep bottom boundary in the finite-element analysis of pavements. A flexible boundary, which accounts for displacements that occur beneath it, is used with finite elements above it. Through case studies it is shown that the method yields accurate solutions. The results are much better than those from a traditional finite-element approach requiring approximately the same amount of computational effort. The proposed method possesses significant advantages over the traditional approach, especially in nonlinear analysis.
Abstract