爆炸作用下淤泥质软土的热力响应试验研究

Tests for temperature and pressure response of silt soft soil under blasting load

针对宁波海相淤泥质软土开展现场模爆试验,获得了不同装药量和埋深条件下软土的孔隙水压力、冲击压力及温度的时程分布和演化规律,揭示了爆炸作用下软土中渗流、应力和温度的耦合现象。试验结果表明:随着药量增大,超静孔隙水压力峰值增大,爆炸后数分钟内孔隙水压力消散较快,随后变慢。爆炸后,软土中冲击波向弹性波转化存在一个分界压力,这个分界压力与介质性质有关系,尤其是含气量。温度在软土介质中具有一定的传导时间和上升时间,且在软土介质中的上升较空气中慢。最后,利用相关理论开展计算,并与实测结果进行了对比分析。研究结果可以为沿海软土地区地下人防工程设计及地基压密处理提供参考。

An in-situ simulated explosion test was carried out at a site with Ningbo marine silt soft soil.The time history distribution and evolution laws of pore water pressure,shock pressure and temperature under the conditions of different explosive quantities and buried depth were obtained. The test results revealed that there exist coupling phenomena of seepage,stress and temperature;the peak of super-static pore water pressure increases with increase in explosive quantity and the dissipation of pore water pressure is relatively quick within early minutes after explosion and then it decreases;there is a dividing line pressure which means a pressure for shock wave to be converted into elastic wave and it is related to soil＆#39;s character,especially,its air content;the explosion temperature has a certain conduction time and rise time in soft soil,and it rises more slowly in soft soil than it does in the air.Finally,relevant theories were used to compute the pressure and temperature.The calculated results were compared with the measured ones.The study results provided a reference for underground people air-defense engineering design and base compaction treatment in coastal soft soil area.