心墙水力劈裂机理的离心模型试验研究

采用直立土柱试样进行离心模型试验的方法，对心墙发生水力劈裂的条件和过程进行了研究。试验结果表明，当土柱上游侧外水压力大于土体压力时，土柱将产生水力劈裂，并最终产生渗透破坏。因此，在心墙土石坝工程中，由于坝壳对心墙拱作用所导致的心墙土压力小于外部库水压力将是产生心墙水力劈裂的根本原因。

Centrifugal model study on mechanism of hydraulic fracturing of clay core wall in rockfill dams

The formation conditions and process of hydraulic fracturing of clay core-wall was studied by centrifugal model test. The specimen was a clay column with rectangular cross section. The result shows that the hydraulic fracturing happens to the specimen when upstream water pressure is higher than the earth pressure acting on the soil core, and seepage fracture occurs consequently. It is conclude that in engineering practice, the hydraulic fracturing will occur if the soil pressure of dam shell acting on the core-wall is less than the reservoir water pressure.