低渗透饱和岩石加载时体积弹模与孔隙液压的关系

RELATION BETWEEN PORE LIQUID PRESSURE AND BULK ELASTIC MODULUS OF LOADED SATURATED ROCK OF LOW PERMEABILITY

低渗透率饱和岩石受单轴压力作用时,由于其本身结构的变形,使得孔隙的液体也受压。受压的孔隙液体通过与外界相通的微小管道排出,使得孔隙液体压力降低,于是外力转嫁给固体结构,通过相应调整适应这种变化。这样,通过一系列的排液变形和调整,最终达到平衡。定量给出了饱和岩石内孔隙液压的前期变化过程、岩石结构受力过程以及饱和体体积弹模的变化过程,并通过试验验证了这一现象的变化过程的合理性,展示了岩石由于结构浸水、胶质软化而在后期刚度下降。

The structure of saturated porous body with low permeability deforms under uniaxial compression load and the liquid in porous is compressed also. The part of compressed pore liquid penetrates throughout the micropipe of body. The pore liquid pressure supporting load is reduced and the load is moved to the solid structure. Thus the equilibrium takes place finally after a serious loading redistribution, reduction of pore pressure and increment of structural deformation. The variation progress of pore pressure and structural deformation in saturated weak rock, and changes of saturated bulk modulus are given, which are confirmed by the results of experiments.