The effect of spherical air blast on buried pipelines: a laboratory simulation study

Abstract

A new laboratory-scale experimental technique has been developed to study the blast wave effects on buried pipelines caused by an explosion at an altitude. A shock tube is used in this study to generate a blast wave in a controlled and repeatable manner, without the use of any explosives. The blast wave profile generated is characterised by peak reflected pressure and positive phase duration and is represented using tri-nitro-toluene equivalents. Shock tube experiments have been carried out on a reduced-scale pipe model in a sand deposit. The momentum transfer from the blast wave to the sand bed is indicated by the presence of compression stress waves. It is demonstrated from the experiments that the shock tube is an effective and versatile tool for investigating the interactions of blast wave with the buried structures. Using the dimensional analysis procedure, shock tube experimental results are scaled up to predict the real-scale damage imparted to the buried pipes during a spherical air-burst explosion. In addition, a three-dimensional finite-element analysis of the test condition is performed to investigate the fidelity of the scaling laws.