Numerical prediction of blast wall effectiveness for structural protection against air blast

Abstract

This paper presents a prediction method for the effectiveness of various blast wall configurations in providing protection against air blast. Shock wave propagation and its interaction with the blast wall were performed in LS-DYNA in order to calculate the overpressure-time histories behind the blast wall. The peak overpressures and specific impulses were determined. The influence of structural flexibility on the blast wall effectiveness was considered by including a metal sheet (“canopy”) at the top of the wall. Three experiments were conducted to measure the blast loads behind the blast wall. During the planning phase of the experiments, numerical models were developed in order to predict the main blast and response parameters. The experiments can then be used to validate the numerical models. If the numerical models are validated, they are able to predict the performance of other blast walls without further experiments. It was found that certain blast wall configurations can reduce the blast effects on buildings. However, there were also unfavorable configurations, where no reduction in the blast effects was found. These studies serve to understand the behavior of air blast interacting with blast walls and identify the principal parameters for the design of such walls.