冻融损伤岩石的强度准则研究

摘要

强度准则在理论研究和工程应用等方面都具有重要意义.将损伤力学和细观统计方法相结合,考虑岩石缺陷的随机性,建立了冻融岩石的损伤本构模型,并推导出模型参数的表达式;根据模型最大主应力点的极值条件,建立了冻融损伤岩石的强度准则,并通过实验结果验证其合理性.研究表明:文中所建立的冻融损伤岩石强度准则能够表征不同冻融循环次数下的极限应力状态,反映岩石强度莫尔包络线的曲线特征;模型参数的理论表达式可反映冻融损伤与岩石变形破坏的一般变化规律,增强了模型的普适性,可为寒区岩土工程材料和结构强度研究提供理论基础.%Strength criterion has important significance in theoretical research and engineering application.Considering the randomness of rock defects,the damage constitutive model of frozen rock is established and the model parameters are derived.The damage statistical strength criterion of rock is discussed according to the extreme conditions of the maximum principal points of the model,and its validity is verified by experimental results.The results of the study show that:The strength criterion of freezingthawing damage established in this paper can indicate the relationship between the internal stress and strain parameters under different freeze-thaw cycles,and reflect the characteristics of the rock strength Mohr envelope curve.The theoretical expression of model parameters can reflect the general regularity of freeze thaw damage and rock deformation and failure,which greatly enhance the adaptability of the model,and can provide theoretical basis for the research of cold geotechnical engineering materials and structure strength.