Full-Scale Testing and Analysis for Blast-Resistant Design

Abstract

A full-scale blast test was conducted on a structure representing a mailroom, constructed with unreinforced masonry walls. The four walls were retrofitted with different quantities of glass fiber-reinforced polymers (GFRP) on the outside face to increase their resistance to the blast load. In addition, shotcrete was added to the inside face of the two long walls. The objective of this test was to validate a method of analysis that can be used to design effective retrofit techniques to contain blast loads. A blast load was produced by the detonation of a $0.91\mathrm{kg}$ $\left(2\mathrm{lb}\right)$ equivalent TNT charge placed near the center of the room. Instrumentation on individual walls monitored the blast pressure and the consequent displacement and velocity of the walls. Although the walls sustained extensive internal damage and plastic deformation, the retrofit was able to withstand the blast load. It was observed through the postmortem analysis of the test that the stiffness of the walls is completely lost at an early stage and only membrane action of the GFRP provides structural resistance.