It is very difficult, if not impossible, to obtain the exact solution for soil and structure interaction of underground R.C. structures. In this work, an approximate solution has been obtained by inserting linkage elements, which takes into account the discontinuous nonlinearity between soil and concrete.
The key points of this work are the modelling interface element to have practical properties and finding ultimate load carrying capacity by nonlinear analysis of underground R.C. structures. The behavior and failure mode of underground structures have been obtained approximately, even if an accurate solution for behavior of discontinuous elements could not be found.
