Selection of a Material Model for Simulating Concrete Masonry Walls Subjected to Blast

One of the most common methods of construction is the use of concrete masonry units (CMU) in the walls of buildings. However, they are vulnerable to blast, and result in collapse, fragmentation, and severe injury to occupants. An understanding of the behavior of CMU walls during blast is key to developing mitigation techniques. Research has been conducted using the finite element method to simulate structural failure due to blast. A common problem faced by model developers is the selection of constitutive relationships that appropriately simulate the behavior of materials subjected to shock loading. This project examined the effect of blast impulse loading on CMU blocks. Finite element models were used to perform direct transient analysis using various material cards available in LS-DYNA, and the results were compared to the results of full-scale blast tests conducted by AFRL. The material card that best agreed with the test results was recommended for use in the models of polymer reinforced masonry walls. The original document contains color images. Prepared in cooperation with Alabama Univ. at Birmingham. Dept. of Civil and Environmental Engineering, contract F08637-02-C-7027.