Study on Numerical Analysis of Cavity Subjected to Inner Step Uniform Pressure Modeled by Boundary Element Method

In this paper, cylindrical cavities under pressure located in full space and half space are separately analyzed. Boundary element method formulated in frequency domain is used to discretize the boundary of the problems. Infinite boundary included in the problems is modeled by a special boundary named enclosing boundary. The response in the time-domain is then obtained from the frequency domain solution using Fast Fourier Transform (FFT) technique. The proposed approach is applied to Selberg problem, which consists of a cylindrical cavity in a full space loaded normal to its wall as well as the one in a half space with the same loading condition. Comparison of the obtained results with the closed form and existing numerical solutions shows that the enclosing boundary of any shape can effectively be used to model radiation of the outgoing waves into infinity. It has also been shown that the Poisson's ratio of the medium is a predominant parameter, which can influence the response of the underground cavities.