水–岩石相互作用力学参数的探讨  

INVESTIGATION ON MECHANICAL PARAMETERS OF WATER-ROCK INTERACTION

作　　者：卢应发[1,2] 孙慧[2] 李建林[1] 吴新星[1] 

机构地区：[1]三峡大学三峡库区地质灾害教育部重点实验室,湖北宜昌443002 [2]武汉大学土木建筑工程学院,湖北武汉430072

出　　处：《岩石力学与工程学报》2009年第10期1995-2005,共11页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(50779030);国家自然科学基金面上项目(50879044);国家科技支撑计划项目(2008BAB29B03);国防科工委资助项目(科工计[2007]838号)

摘　　要：水–岩石相互作用是一个非常复杂的过程,鉴于水对裂纹的强敏感特性,利用这种特性探讨岩石的一些基本物理力学性质。现行广泛采用的试验方法有真、假三轴试验,通过分析试验理论和加载测量技术,提出真、假三轴试验在无水压力和有水压力条件下,各自试验可以获得的力学参数个数;指出假三轴试验适合于研究各向同性材料,给出以六面体试件(5cm×5cm×10cm)实施假三轴试验可以研究孔隙介质材料各向异性力学特性的观点。利用水压力卸载对孔隙介质材料力学特性影响较小的特点,提出以水压力卸载试验确定各向异性Biot系数理论和试验方法及相应力学参数的观点。试验结果表明,各向异性Biot系数在不同方向的变化趋势也不相同;利用水–岩石相互作用特征,提出一种新的确定岩体石屈服极限应力的方法,即以偏应力与水压力关系曲线水压力最大值所对应的偏应力为屈服极限应力。试验结果显示,Skempton系数分散性较大,在注水和非排水试验中,水压力的作用机制也不尽相同。这种研究对损伤力学和土木工程实践具有重要意义。The processes are very complex for the coupling of water-rock interaction, and the sensitivity of water to porous media material cracks should be focused for the research of fundamental mechanical properties of rocks. The conventional used test methods are true and pseudo triaxial tests： and the theories and measure technologies of ture and pseudo triaxial tests are also analyzed. The mechanical parameters are obtained by ture and pseudo triaxial tests with/without water pressures. The idea that the triaxial test is only suitable for the isotropic porous media materials is proposed： and the hexahedron sample of 5 cm×5 cm× 10 cm is proposed to conduct the triaxial test to understand the anisotropic mechanical behaviors of porous media materials. The obtained testing methods of anisotropic Biot coefficient and mechanical parameters under different stress states are proposed by using the influences of unloading water pressure on porous media materials. The testing results show that variational trends of anisotropic Biot coefficient in the different directions are not the same. The testing method of limit yield stress is suggested： the limit yield stress is equal to the deviatoric stress corresponding to the maximum water pressure of curve between deviatoric stress and water pressure. The testing results also show the Skempton coefficient disperity is significant; and the mechanism of water pressure action is different under various injections and drainages. It is crucial for damage mechanics and civil engineering to research water-rock interaction.

关 键 词：岩石力学 水-岩石相互作用 真 假三轴试验 屈服极限应力 各向异性Biot系数 作用机制 

分 类 号：TU45[建筑科学—岩土工程]