基于三轴压缩试验确定岩石的Hoek-Brown软化参数的方法

A Way of Determining the Hoek-Brown Softening Parameters of Rocks from the Triaxial Compression Test

简要介绍岩石的Hoek-Brown应变软化模型后,以花岗岩的三轴压缩试验为背景,利用数据拟合的手段,通过假设单轴压缩试验下花岗岩软化段上偏应力与剪应变的关系与理想情况时的相同,给出了确定Hoek-Brown模型中软化参数的方法。然后根据确定出的软化参数在FLAC3D中利用Hoek-Brown软化模型对花岗岩的三轴压缩试验进行数值模拟,并与试验结果比较,两者比较吻合。这说明了所提出的软化参数确定方法的合理性,同时也表明了用Hoek-Brown软化模型来模拟岩石的应变软化现象是行之有效的。

First,the strain-softening model of rock based on the Hoek-Brown strength criterion is introduced briefly.Assuming the relationship between deviator and shear strain at the softening stage of granite under uniaxial compression is the same as idealized response,a method of obtaining the softening parameters in the Hoek-Brown model from the triaxial compression test is then given by the way of data fitting.At last the Hoek-Brown softening model in FLAC3D is used to simulate the triaxial compression test of granite by using the calculated softening parameters.It turns out that the result of numerical simulation matches the experiment well,which proves that the method put forward in this paper is reasonable and Hoek-Brown softening model can simulate the strain-softening phenomenon of rock effectively.