科技通报

爆破挤淤抛石法通过在抛石体外缘一定距离和深度的淤泥质软基中埋放炸药包群，引爆后瞬间产生巨大的压力形成空腔，同时抛石体借助自身重力在受到爆炸冲击力作用下沿着斜面滑移填充空腔形成石舌，形成泥石置换的效果，从而实现了软土地基的加固，其广泛应用于淤泥地基的处理。该方法中抛填石的落底深度是评判其加固地基效果的重要指标，本文采用探地雷达技术对滨海公路现场爆破挤淤加固的路基进行落底深度探测分析，在对爆破挤淤后的抛石层进行探测时，根据抛石的介电常数与淤泥和黏土有较大的差异，并且通过对雷达图像的解释和分析，得到回填置换层深度。结合实际工程，探讨采用地质雷达评估爆破挤淤效果，通过分析对比可知，40 MHz低频组合天线可用于探测抛石层在25 m左右的下落深度，达到了预期的探测深度和精度要求。

Explosive replacement and riprap is to bury explosive packs in the silt soft foundation at a certain distance and depth from the outer edge of the riprap. After explosion, a huge pressure is generated to form a cavity immediately; at the same time, the riprap is impacted by its own gravity, it slides along the slope and fills the cavity to form a stone tongue, which forms the effect of mudstone replacement, thus realizing the reinforcement of soft soil foundation, which is widely used in the treatment of silt foundation. In this method, the bottom depth of riprap is an important index to judge the effect of foundation reinforcement. In this paper, the ground penetrating radar technology is used to detect and analyze the bottom depth of the subgrade reinforced by the explosive replacement on the coastal road. When the riprap layer is detected, the dielectric constant of the riprap is quite different from that of silt and clay, and the depth of the backfill replacement layer is obtained through the interpretation and analysis of the radar image. Based on actual engineering, the use of geological radar to evaluate the effect of explosive replacement is discussed. Through analysis and comparison, it is known that the 40 MHz low-frequency combined antenna can be used to detect the falling depth of the rock dump at about 25 m, which meets the expected detection depth and accuracy requirements.