水-岩化学作用之岩石断裂力学效应的试验研究

在常温常压，不断循环上，对不同化学性质的水溶液上的两种花岗岩和两种砂岩进行了断裂力学指标KIC和δc的三点弯曲试验。结果表明：（1）水－岩化学作用对岩石裂纹的断裂指标有显著的影响，并且具有时间效应。不同岩性，不同浸泡方式及不同水溶液流动速率对岩石断裂力学指标的影响存在着较大差异。总体上，水化学作用对断裂力学指标的影响程度与水－岩化学反应的强度成正比。（2）岩石中的含铁离子或钙离子的矿物及胶结物成分是水－岩化学作用力学效应的关键物质成分，其中含铁离子物质对水－岩反应的断裂力学效应具有正反两方面的水学效应。

TESTING STUDY ON EFFECTS OF CHEMICAL ACTION OF AQUEOUS SOLUTION ON CRACK PROPAGATION IN ROCK

The fracture mechanics effects of chemical action of water-rock and their time-dependent and chemical environment-dependent behaviors in grey granite,green granite,grey sandstone and red sandstone are analyzed by test of KIc and COD for rock under different conditions. The fracture mechanics effect of chemical action of water-rock is evident and time-dependent. The big differences exist for the influence of different aqueous solution,different rocks,different immersion ways and different velocity of cycle flow on the fracture mechanics effects of rock. The mechanical effect of water-rock interaction on propagation of fracture is consistent with the mechanical effect on the peak strength of rock. The intensity of the fracture mechanics effect increases with the intensity of chemical action of water-rock. Iron and calcium ion-bearing mineral or cement in rock are some key ion or chemical composition,and especially iron ion-bearing mineral resulting in chemical action of water-rock is provided with both positive and negative mechanical effects on rock.