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用采自现场的５００ｍｍ×５００ｍｍ×１０００ｍｍ的天然灰岩，在注水条件下模拟扩容－扩散（Ｄ－Ｄ）孕震模式，并以多种监测手段追踪受载岩石样品从变形、微裂到大破裂全过程有关的物理场的时空演化特征．分析视电阻率结果表明：①受载岩石从微裂到大破裂全过程与电阻率前兆的时空演化进程基本吻合；②电阻率前兆的时间进程具有“阶段性”，空间分布具有“差异性”；③岩石大破裂前观测到明显的“趋势”异常和“短期”前兆，并发现部分似可被确认为“临震”异常的电阻率前兆．电阻率的变化和分布特征似乎显示了与岩石样品受载过程的膨胀现象有某种内在联系．但未找到岩石膨胀的直接证据．最后，从理论上探讨了受载岩石样品电阻率变化的机理．
Using natural limestone of 500 mm × 500 mm × 1000 mm collected from the field, the D-D seismogenic mode was simulated under the condition of water injection, and the deformation of the rock specimen under load from micro-cracking to large Spatiotemporal evolvement of physics related to the whole process of rupture. The analysis of apparent resistivity shows that: (1) The time-space evolution of resistivity precursors coincides with the whole process of micro-cracking to large-scale rupture of the rock under load; (2) the time course of resistivity precursors is “staged” and the spatial distribution has “difference” ; ③ Significant “trend” anomalies and “short-term” precursors were observed prior to the large rupture of the rock and some were found to be identifiable precursors of resistivity anomalies. The variation and distribution characteristics of the resistivity seem to show some intrinsic relationship with the swelling of the rock sample during loading. But no direct evidence of rock expansion was found. Finally, the mechanism of the change of resistivity of rock samples is discussed theoretically.