岩石三轴压缩任意围压下应力–应变曲线的预测方法研究

Forecast of stress-strain curves of rock under arbitrary confining pressures in triaxial compression

岩石三轴压缩试验中通常只做有限种围压情况下的压缩试验,得到的应力–应变曲线只是岩石在具体围压下本构关系的表现,限制了通过拟合应力–应变曲线得到岩石本构的实用性。认为不同围压下的应力–应变曲线虽然形状差别较大,但都是同种岩石所表现出来的特性,曲线间蕴含着一定联系。对此进行了研究,并提出一套基于有限种围压情况下的应力–应变曲线预测任意围压下应力–应变曲线的方法。通过实例,说明所提方法的可行性。

Generally, rock triaxial compression tests were done under limited different confining pressures. The stress-strain curves obtained under certain confining pressure reflected certain constitutive relation of the rock, and the practicability of studies on the constitutive relation of rock was limited to fitting stress-strain curves. It was considered that the stress-strain curves under different confining pressures were different greatly in shapes, but there should have be some relationship because these curves were the responses of the same rock. A method was proposed to forecast the stress-strain curves under arbitrary confining pressures based on the stress-strain curves obtained under the limited confining pressures. An example was studied, and it was shown that the proposed method was feasible.