Response of Structures to Combined Blast Effects

This paper describes methods of computing dynamic structural response, including interaction between the structure and surrounding soil. Two applications of the finite element method to the dynamic response of a small structure embedded in sand are described. One application involves a three dimensional analysis in which the soil is represented by continuum elements and the structure by plate elements. The second application involves an axisymmetric approximation of the structure, in which the effects of nonlinearity of the soil and slip between soil and structure are accounted for. Comparison is made between the analyses and measurements made during the physical experiment which was conducted at U.S. Army Waterways Experiment Station, Vicksburg, Miss. The main goal of the paper is to assess the capabilities and limitations of existing finite element methods to predict response under these conditions. Satisfactory agreement in the frequency domain between about 40 to 200 cps was obtained. A correlation at higher frequencies was not attempted.