非均匀软岩蠕变机理分析

为了对工程围岩的蠕变现象进行解释，探明软岩的蠕变本质，根据岩石压缩过程中变形、弱化本构关系以及变形与承载能力的关系，采用岩石最弱断面并联微元体模型，对非均匀软岩的衰减蠕变和非衰减蠕变机理进行了分析，研究表明，非均匀性岩石内部各点承载能力不同使得变形后岩石内部各点屈服弱化不同步，又由于岩石晶体内部空位或杂质的扩散，二者共同作用导致岩石蠕变．通过对截面积相同，高径比分别为1．5和2．5的页岩岩样进行蠕变试验，验证了岩石的非均匀性是造成岩石蠕变的一个不可忽视的重要因素．

Analysis of Creeping Mechanisms of Non-Uniformity Soft Rocks

In order to explain the creep phenomenon of surrounding rock in the engineering and explore the essence of creep,based on the constitutive relations between deformation and softening and the relations between deformation and bearing capacity of rock during compressing,the creep mechanisms of soft rock of non-uniformity was investigated by using the parallel infinitesimal model in the weakest section.The results show that the creep is caused jointly by vacancy and impurity diffusing,and non synchronous plasticity deformation weakness due to different inner bearing capacities at different points in rocks because of non-uniformity.The uniaxial compressive creep experiment on shale rock samples with the same section and the height to diameter ratio of 1.5 and 2.5 was made respectively;the results show that the non-uniformity of rock is not an ignorable factor inducing rock creep.