炭质板岩三轴压缩蠕变特性及其本构模型

采集兰渝铁路木寨岭隧道炭质板岩制备试样,开展了三轴蠕变试验,研究了不同层理面与轴向荷载夹角下的试样蠕变特性.根据试验结果提出了岩石横观各向同性蠕变本构模型,由于炭质板岩性质的方向性,其蠕变势函数与常规势函数相比需要更多的参数.此外,结合试验数据开展了蠕变参数反分析研究,可以减少蠕变试验数目,在工程应用中具有一定优势.研究结果为了解岩石横观各向同性和制定相关地层支护方案提供了科学依据.

Creep Characteristic of Carbonaceous Slate and Its Constitutive Model Under Triaxial Compression

Triaxial compression creep tests were performed on carbonaceous slate samples obtained from Muzhailing tunnel of Lanzhou-Chongqing railway in order to understand the creep characteristics of carbonaceous slate with different angle between bedding planes and axial load. Based on the test results， a creep model was proposed to describe the transversely isotropic creep behavior of the carbonaceous slate， which needs more parameters in the creep potential function to describe the transversely isotropic creep behavior than in the conventional potential function. A method for the determination of creep parameters was developed using back analysis， which is helpful in reducing the number of creep tests needed to determine the creep parameters and is applicable in practice. This study contributes to the understanding of the transversely isotropic behavior of rocks and to the design of the lining system in the transversely isotropic stratum.