Shearing of saturated clays in rock joints at high confining pressures
Shearing of saturated clays in rock joints at high confining pressures
复制标题
高围压下岩石节理中饱和粘土的剪切
DOI：
--
复制
发表时间：
1979
期刊：
影响因子：
--
通讯作者：
N. Mao
中科院分区：
文献类型：
--
作者：
Chi‐yuen Wang;N. Mao
饱和粘土在各种孔隙水压力和高达3kb （300 Mpa）的围压下在岩石节理之间剪切。在这些关节上滑动是稳定的。对于给定的粘土，启动滑动所需的剪应力随滑动面上的有效法向应力线性增加，饱和蒙脱土的剪应力斜率为0.08 +- 0.01，饱和绿泥石的剪应力斜率为0.12 +- 0.01，饱和高岭石的剪应力斜率为0.15 +- 0.01，饱和粉质伊利石的剪应力斜率为0.22 +- 0.02。因此，在高围压下，饱和粘土节理启动滑动所需的剪应力要比清洁岩石节理或干泥节理启动滑动所需的剪应力小得多。在地壳中，沿活动断层的泥质饱和会大大降低断层的摩擦阻力，从而稳定断层的运动。不同的断层行为，如沿某些断层的稳定蠕变和沿其他断层的间歇性但突然的滑动，可能在一定程度上反映了断裂带在深部的不同饱和程度。
Saturated clays are sheared between rock joints at various pore water pressures and at confining pressures up to 3 kb (300 Mpa). Sliding on these joints is stable. For a given clay, the shear stress required to initiate sliding increases linearly with the effective normal stress across the sliding surface, with a slope of 0.08 +- 0.01 for joints filled with saturated montmorillonite, 0.12 +- 0.01 with saturated chlorite, 0.15 +- 0.01 with saturated kaolinite, and 0.22 +- 0.02 with saturated silty illite. Thus at high confining pressures the shear stress required to initiate sliding on joints filled with saturated clays are very much smaller than that required to initiate sliding on clean rock joints or on joints filled with dry gouge materials. In the crust, saturation of gouge materials along active faults would greatly lower the frictional resistance to faulting and would stabilize fault movement. Different fault behaviors such as stable creep along some faults and intermittent but sudden slip along others may reflect in part different degrees of saturation of fault zones at depth.