A RAPIDLY ERECTED TEMPORARY STRUCTURE PROTECTING FROM POWERFUL EXPLOSIONS

A design of a rapidly erected temporary structure reducing adverse factors of a powerful explosion to the levels safe both for people and building structures is proposed. The protective structure consists of three separate metal frames with the open upper part, welded or bolted to each other and covered with metal profile. Each frame houses reservoirs of watertight cloth filled with water. Damping of an air shockwave has been numerically modeled, and a full-scale rapidly erected temporary protective structure has been tested with an explosion of a home-made 100kg-trotil equivalent explosive device installed in a car. The explosion process and its impact on the protective structure were numerically modeled in a hydrodynamic formulation, where the structure prior to the beginning of failure was regarded as a rigid non-deformable body. According to the computational results, a rectangular geometry of the frame is more effective than a trapezoidal one. The parameters of the air shockwave were measured with SPK-sensors according to the certified and registered in the State Register methodology “SVР20-VUV” providing measurement of pressure amplitudes to the accuracy of not more than ±11 %. The numerical results are compared with the results of tests of the proposed design of a protective structure. The numerical and experimental data on the peak value of pressure without the protective structure satisfactorily agree Sadovskiy's formula for a ground explosion. Times of arrival of the air shockwave and maximal pressures along its front in the control points in front of and behind the protective structure obtained numerically and experimentally agree within measuring accuracy.