Finite element method computations in unbounded domains with nonzero but uniform far field decay

The infinite elements were invented to extend the applicability of finite element method to large class of unbounded domain problems, which occur in abundance in engineering and science. The existing state of the art on infinite elements is adequate to solve unbounded problems provided the variables of analysis decay to zero at infinity. Not enough problems and computational experience are available to achieve the same when the decay to infinity is nonzero. This paper presents the problem of excavation of a circular underground opening in a medium with non-hydrostatic initial stress field. Since the stresses at infinity are not zero, the conventional infinite element implementation leads to erroneous results. This is effectively corrected by the suggested strategy.