冻结壁发育状况的地质雷达探测研究

Research on Ground Penetrating Radar (GPR) Exploration on Artificial Frozen Wall Development

根据冻结工程中冻土和未冻土之间介电常数和电阻率的差异,研究了地质雷达探测冻结壁发育状况.采用时域有限差分法模拟冻结不同阶段的冻结壁的发育状况,获取冻结壁在雷达剖面上的反映特征,据此指导工程实测.计算结果和探测实例均表明,地质雷达可用于冻结壁发育状况的探测,查明其中的缺陷,便于及时处置冻结工程中可能出现的问题,是确保冻结工程安全的有效手段.

Based on the difference in dielectric constant and resistivity between unfrozen soil and frozen soil of artificial freezing engineering, the ground penetrating radar (GPR) method was used to explore the development of artificial frozen wall (AFW). Different development stages of frozen wall was simulated by finite difference time domain (FDTD) method with absorb boundary condition (ABC). Some engineering examples are given to illuminate the effect of GPR exploring. Both numerical simulations and engineering examples show that GPR is an effective method of monitoring AFW development and can be used to detect AFW lacunas in time.