用实验方法研究了500mm×500mm×1000mm的大型天然灰岩样品从微裂到大破裂的电阻率前兆特征,对资料的初步分析表明:(1)电阻率异常的时空演化进程与岩石从受力、变形到破坏的整个过程密切相关;(2)电阻率异常的空间分布具有差异性,时间演化具有阶段性;(3)在整个加载过程中电阻率变化有明显的“趋势”异常,岩石大破裂前观测到了“短期”前兆和“临震”突变。这些实验结果为大地震前野外地电阻率法观测资料的物理解释提供了实验依据。最后,利用所观测到的电阻率前兆特征对受载条件下灰岩样品的变形破坏过程进行了初步讨论。 The resistivity precursory characteristics of a 500 mm × 500 mm × 1000 mm large natural limestone sample from micro-cracking to large-scale rupture were studied experimentally. The preliminary analysis of the data shows that: (1) the temporal and spatial evolution of resistivity anomalies is related to the evolution of the rock from the stress (2) the spatial distribution of resistivity anomaly has the difference and the time evolution has the stage; (3) there is obvious “trend” anomaly in the change of resistivity during the whole loading process, the rock is big Pre-rupture observed “short-term” precursors and “temporary” mutations. These experimental results provide experimental evidence for the physical interpretation of the field resistivity method before the earthquake. Finally, the deformation and failure processes of the limestone samples under the loading conditions are discussed with the observed precursors of resistivity.