基于热力学的混凝土塑性和粘塑性本构模型研究

建立了具有实用意义的基于热力学能量耗散函数的混凝土率无关和率相关塑性模型.基于热力学原理,构造了混凝土在主应力空间中的能量耗散函数,并根据此函数推导出了耗散应力空间和真实应力空间中的混凝土模型.推导过程中不需引入其他假定,所得模型能自动满足热力学定理.拟合参数后,计算了多种受力状态下混凝土试件和构件的静动态响应.计算结果符合试验结果,验证了模型的正确性和实用性.

Research on plastic and viscoplastic constitutive model of concrete based on thermodynamics

A practical rate-independent and rate-dependent plastic model of concrete is presented based on thermodynamic energy dissipation function. Starting from the principle of thermodynamics, an energy dissipation function is constructed in the principal stress space, from which concrete models in dissipative stress space and real stress space are derived. No other postulate is needed in the derivation, and the results satisfy thermodynamics theory automatically. With the identified model parameters, static and dynamic behaviors of concrete specimens and structure standing various loadings are simulated. The performance affirms the correctness and the validity of the model.