Field Verification of Millisecond Delay Blast Densification of Sand

实验室测试预测，毫秒级延迟的全尺寸现场爆破致密化砂的效果至少与一次重量等于延迟总和的大爆炸致密化砂的效果一样，而且产生的振动更少。在这项研究中，冲击加速度计和动态压力计将测量爆炸产生的地面运动和压力。荷兰锥贯仪和膨胀仪将记录土壤的贯入阻力和模量随时间和爆炸距离的变化。将绘制爆炸能量、地面运动、产生的压力、土壤改良程度、改良的空间范围和时间之间的关系。将评估目前现场仪器的发展是否足以应付动态事件。

Laboratory tests have predicted that full-scale field blast-densification of sand with millisecond delays will be at least as effective and generate less vibration as densification by a single large blast equal in weight to the sum of the delays. In this research, shock accelerometers and dynamic piezometers will measure the ground motions and pressures generated by the blasts. A Dutch cone penetrometer and a dilatometer will record changes in the soil's penetration resistance and modulus with time and distance from the blast. Relationships will be drawn between explosive energy, ground motion, generated pressures, the degree of soil improvement, the spatial extent of the improvement, and time. Assessments will be made as to whether current developments in situ instrumentation are adequate for dynamic events.