Effect of Stratification on Underground Opening: A Numerical Approach

Due to the increase in urbanization and requirement of rapid transportation and storage purpose, the demand for various underground structures has been exponentially increased. Underground structures like tunnel, subways, and storage tank have been constructed to fulfill the requirement of the urban society. In the present paper, two-dimensional finite element analysis has been performed using finite element program, ABAQUS. The settlement and the effective stresses in the tunnel liner due to the stratification of soil have been analyzed. The geostatic stress of soil has been calculated to fix the initial condition of site which is used for simulating the other phase of construction. It has been found that stratification has not much affected the stresses on the liner. Maximum value of stresses has been observed at the Springer level and crown level. However, the vertical displacement has been reduced by 27% when the silty sand (SM) layer moves closer to the crown of opening. Lateral displacement has not much affected by the stratification. However, the maximum value of lateral displacement was reported near mid-axis of opening in each case.