基于Weibull分布的石砌体单轴受压损伤本构模型

Constitutive Model of Masonry under Uniaxial Compression Based on Weibull Distribution

石砌体的本构模型是石砌体力学计算和有限元数值模拟的重要基础和前提条件。为了深入研究石砌体单轴受压下的本构关系,基于损伤力学理论,应用双参数Weibull分布函数反映损伤变量,根据石砌体单轴受压应力-应变全过程曲线的特征条件确定其参数,推导并建立了石砌体单轴受压损伤本构模型,将已有试验数据验证本构模型的正确性,并将本构模型与典型的砌体本构模型进行对比分析,最后应用本构模型对已有石砌体拱桥试验进行有限元分析以验证本构模型的适用性。结果表明:所建模型与已有石砌体单轴受压试验结果吻合良好;所建模型验证了石砌体损伤演化的一般规律,符合典型的砌体本构模型的一般趋势;所建模型可应用于石砌体结构有限元分析计算,适用性良好。

Constitutive model of stone masonry is an important foundation and prerequisite for physical calculation and finite element numerical simulation of stone masonry.In order to further study the constitutive relationship of stone masonry under uniaxial compression,based on the theory of damage mechanics,the two-parameter Weibull distribution function was applied to reflect the damage variable,and its parameters were determined according to the characteristic conditions of the whole process of the stress-strain curve of stone masonry under uniaxial compression.The uniaxial compression damage constitutive model of stone masonry was derived and established,and the correctness of the constitutive model was verified by the existing test data.The constitutive model was compared with the typical masonry constitutive model.Finally,the finite element analysis of the existing stone masonry arch bridge test was carried out to verify the applicability of the constitutive model.The results show that the model is in good agreement with the uniaxial compression test results of existing stone masonry.The established model verifies the general law of masonry damage evolution and accords with the general trend of typical masonry constitutive model.The model can be applied to the finite element analysis and calculation of masonry structure with good applicability.