爆炸荷载作用下土中爆坑形成的数值模拟

Numerical simulation of craters produced by explosion in soil

利用爆破产生能量可进行软基处理,但不同药量、不同药包埋设深度下爆坑形态和土体属性变化会存在差异。采用基于欧拉法的爆炸流体动力学数值模拟技术对土中爆破问题进行了分析,结果表明,最终爆坑形态与已有试验成果具有较好一致性;爆坑直径与药量和埋药深度存在一定的非线性关系;爆炸荷载在近域传播与冲击波类似,随着远离药包中心,则表现为应力波特征;随埋药深度增加,爆破挤密效果明显,但浅层爆破对土体挤密效果有限。

Energy produced by explosion in soil can be used to improve soft foundation. The shape of crater and variation of soil properties are different under different conditions of charge masses and buried depths. Numerical simulation technology of explosive fluid dynamics based on Euler formulation is adopted to analyze explosion problem in soil. The result shows that the final shape of crater is consistent with the obtained field results; and nonlinear relation between crater diameter and charge mass and btlried depth is obtained. The pressure wave has the similar feature of shock wave at the near field; and then as the wave propagating from the charge centre, it changes to the stress wave style with reduced amplitude. With increase of buried depth, the compaction effect is more distinct; but the compaction effect produced by explosion in shallow layer of soil is quite limited.