岩石脆延特性转化条件确定的统计损伤方法研究

Study on decision of conversion condition for brittle-ductile property of rock by statistical damage method

针对Lemaitre应变等价性假说的局限性与不足,通过引进统计损伤理论,基于岩石三轴试验曲线,建立了能够反映脆延特性及其相互转化特征的岩石损伤统计本构模型。在此基础上,通过探讨岩石脆延特性及其相互转化的力学机理与特点,利用多元函数求全微分的分析方法,建立了岩石脆延特性相互转化条件的确定方法,它能同时反映岩石所受荷载情况与本身力学性质对岩石脆延特性及其相互转化特征的综合影响,试验结果与理论分析结果表明了本文研究成果的合理性与可靠性,进一步完善了岩石本构关系的研究内容。

Aiming at some restricts and deficiencies of strain-equivalence hypothesis of Lemaitre and through introducing a statistical damage theory, a new statistical damage constitutive model was established based on the curves obtained from tri-axial tests, which could reflect mutual conversion for brittle and ductile properties of rock. On such a basis, through deep discussion of the mechanical mechanism of brittle or ductile properties and their mutual conversion, a new way to determine the conversion condition for brittle-ductile properties was developed by solving differential of pluralistic function. It could simultaneously reflect the combining effects of load condition and mechanical properties of rock itself on brittle or ductile properties and their conversion. The comparison between results of tests and theoretical analysis shows that the method is reasonable and reliable, and it will improve the studies on the constitutive relation of rock.