Attenuation effect of sand on blast wave was studied. Two spherical PMMA containers of 100 mm and 200 mm, respectively, were prepared and each filled with sand. Spherical pentolite (100 g) was ignited at the center of the each container. Three pressure transducers were placed around the container and the blast pressure was measured. The scaled distance from the charge, to each of the three transducers, were 3, 4, and 5 m·kg-1/3, respectively. The 200 mm-diameter container was the more effective for decreasing the peak pressure and the impulse. The peak pressure and the impulse decreased to 21-27 % and 37-40 %, respectively, in comparison to that without the sand. The attenuation effect of sand was larger than that of water gel and/or foam polystyrene for same volume.
爆薬を砂（相馬砂特4号）で覆った状態で点火し，周囲における爆風圧力の時間履歴を計測することにより，砂が爆風圧を低減する効果の評価を行った。外径100 mm，200 mmの2種類の大きさのアクリル製球形容器を用意し，砂を満たした。100 gの球形ペントライトを容器中心に設置し，点火した。換算距離3, 4, 5 m·kg-1/3の３点で爆風圧の計測を行った。200 mm容器の時に低減効果が大きく，ピーク圧力は，緩衝材がない場合の21-27 %であった。また，正相のインパルスは，緩衝材がない場合の37-40 %であった。緩衝材として同体積のゲル化水・発泡スチロール混合物を用いた場合に比べて，爆風圧低減効果は大きかった。
Blast wave, Attenuation, Sand