Finite Element Analysis of an Underground Structure.

Abstract : The evaluation and design of underground structures subjected to blast loads are presently based upon empirical correlations of field studies and some numerical analysis of structural components. Recently, the United States Air Force initiated an investigation of the feasibility of implementing analytical procedures and computer models to evaluate the response of these structures. This study was concerned with the evaluation of the finite element program NONSAP-C (nonlinear elasto-dynamic finite element program) as a means to predict the response of a structure subjected to different loading conditions. The evaluation was made by comparing the predicted responses with the observed responses from laboratory tests. These tests were performed on laboratory scaled structures with simple geometry. These types of tests were conducted on the scaled structures. The first two tests consisted of the application of static dynamic loads to a scaled concrete structure. The third test consisted of the application of an explosive load to a scaled concrete structure buried in dry sand and subjected to a high gravity environment. The three types of tests were simulated with the program NONSAP-C.