脆性岩石损伤断裂机理分析与试验研究

为了探讨渗透水压力对脆性岩石损伤劣化的影响，及脆性岩石变形过程中渗透特性的变化规律，分别取三峡船闸高边坡花岗岩和山西万家寨水电站灰岩进行不同应力状态的全应力-应变过程渗透性对比试验，然后将其岩石破坏断裂断口进行微观扫描电镜试验。试验结果反映出脆性岩石破坏前后渗透特性具有明显差异，从而也表明渗透水压力对岩石裂隙张开度与扩展变形起到一定程度的加剧作用。通过不同层次的试验研究与理论分析，给出了渗透水压作用下岩石破裂产生的微观破坏力学机制，为进一步分析暴雨入渗状态下水压急剧上升与聚降对裂隙岩体高边坡失稳的机理提供了可靠的试验依据。

MECHANISM ANALYSIS AND TESTING STUDY ON DAMAGE AND FRACTURE OF BRITTLE ROCK

In order to probe into the damage and degradation influence of seepage pressure on brittle rock and the seepage characteristic law during the deformation of brittle rock,the brittle rock specimens collected from the Three Gorges shiplock slope and the site of Wanjazhai hydraulic power station are tested antithesesly under different stress levels. Then,the microtest,SEM,is carried out to study the failure surface of brittle rock. The testing result indicates that the seepage character of brittle rock is of district difference before and after failure. So,it is concluded that the seepage pressure makes the effect strongly on the fracture and dilatation of rock. Based on the theoretical analysis and testing study on the damage and fracture of brittle rock,the mechanism of crack initiation and micro failure of rock under seepage pressure is gotten clearly. And,reliable testing basis is offered to analysis on the weathered rock instability of high slope under the condition of water pressure suddenly rising or falling during the oozing of rainstorm.