基于扰动状态理论的大理岩三轴受压响应描述

Tri-axial Compressive Response Description of Marble Based on Disturbed State Concept Theory

应用扰动状态理论准确拟合大理岩常规三轴受压实验全过程应力应变关系曲线.实验在RMT150B岩石力学实验系统下完成,得到明显的软化段曲线.在弹性模量和扰动因子材料参数的表达式中显含围压,可以模拟材料在不同埋深情况下的响应.扰动因子的取值与本构模型无关.从压密点开始描述应力应变关系,压密点提供理论曲线的初始值.扰动状态理论的平均化思想允许把软化问题作为硬化问题处理,得到连续的包括软化段的全过程曲线,且保持在应力空间中解决应力应变关系描述问题.理论曲线与实验曲线对比体现了扰动状态理论对岩石应力应变关系的有效拟合.

Disturbed state concept theory （DSC） gives qualified fitness of stress-strain softening phase of marble under regular tri axial compressive test. Steady softening phase of the stress-strain curve shows the ability of RMT-150B rock experimental instrument. Elastic modular and disturbance factor parameters change with confining pressure of the tri-axial compressive test, so the responses of material at different setting depth can be depicted. The disturbance factor is unassociated with the constitutive model. Stressstrain relationship is described after the compaction point of rock, and the compaction point provides the initial value of the computation for the stress-strain curve. The averaging thought of disturbed state concept theory permits treatment of softening as hardening and the entire phase of the continuous stress-strain relationship curve is obtained. DSC keeps within stress space to discuss the stress-strain relationship de- scription. The comparison of theoretical computation curve and experimental curve proves the effectiveness of the fitting carried out by DSC.