Blast Load Analysis and Simulation of Unreinforced Concrete Masonry

Abstract

This study presents an innovative blast analysis tool that can be used in assessing blast performance of concrete masonry walls. The analysis tool proposes a structural model of unreinforced masonry (URM) walls, and a simplified procedure to generate load histories on structures subjected to blast loading. This study focuses on hollow concrete masonry units (CMU) walls. Three-dimensional masonry walls are modeled using discrete rigid bodies connected by nonlinear springs. Connections between two masonry blocks attached by mortar joint are modeled by treating adjoining springs as springs in series. The blast load histories are calculated using UFC 3-340-02. The proposed tool generates individual load-time histories for each discrete elements of a wall. The individual load-time histories, and the peak pressure distribution on a wall surface, are compared to experimental measurements to validate the blast-load-generating algorithm. The two modules (blast-load, and numerical model generator) are then used to simulate an actual experiment on URM wall for validation. For this study, experiments on URM wall arching is simulated. The proposed tool is able to approximate the wall response, particularly, the maximum positive and negative displacements. The good agreement proved the applicability of the proposed analysis tool to the analysis of URM walls.