Blast Response of Cellular Cement Foams: An Experimental Evaluation

Abstract

뀀ഀȠ ABSTRACT Results from an experimental investigation into the dynamic response of cement foams subjected to blast pressure loading are reported in this paper. Cement foams with a cellular structure consisting of large entrained porosity in the form of uniformly distributed air cells were used in the study. The quasi-static response of such foams exhibits a distinctive concave shape associated with crushing of cell, which follows an initial linear elastic response. Experimental results from cement foam subjected to different blast pressure loadings using a shock tube are presented. Experimental results show a clear beneficial effect in reducing the amplitude of the transmitted stress. Results indicate that crushing of foam produces a continuous decrease in the amplitude of the stress wave produced in the foam. The blast pressure loading applied at one end of foam specimen is transmitted to the substrate as a stress pulse of reduced amplitude. When sufficient length of the foam is present, the transmitted stress history due to an applied blast pressure wave resembles a rectangular stress pulse of amplitude slightly higher than the crushing strength of the foam. The transmitted stress amplitude to the structure can effectively be controlled by varying the crushing strength of the foam.