两类混凝土动力黏损伤本构模型比较研究

Comparative Studies of Two Types of Viscous Damage Models for Concrete Under Dynamic Loading

摘要:

在混凝土弹塑性损伤理论框架下，为反映材料力学行为的率相关性，对静力损伤演化进行了动力扩展。混凝土在动力加载下的损伤演化滞后于静力加载而引起强化现象，借鉴黏塑性理论，在损伤子空间建立了两类格式的动力黏损伤演化模型：Perzyna模型和Duvaut-Lions模型。分别从本构理论和数值计算结果上对两类黏损伤演化模型进行了对比研究。从理论上来看，两类模型具有不同的黏性化变量；从模拟结果上来看，两类格式的线性黏损伤模型的计算结果基本重合，而两类非线性的黏损伤模型得到的结果存在差异。另外，两类非线性的黏损伤模型预测的混凝土动力强度的提高与试验数据吻合较好，说明均可反映混凝土材料的率相关性。

Abstract:

In order to reflect the rate dependence of mechanical behavior under dynamic loading， based on the elastoplastic damage theory framework， the dynamic damage evolution is expanded from the static model. The damage evolution is delayed due to the rate effect， which leads to the strengthening phenomena. Inspired by the viscoplastic theory， two types of dynamic visco-damage evolution models are established in the damage subspace： Perzyna model and Duvaut-Lions model. The constitutive theories and the numerical results of the two kinds of viscous damage evolution models are compared respectively. In terms of constitutive theory， the two models have different viscous variables. In the simulation results， concrete dynamic behaviors simulated by the linear visco-damage models with Perzyna format and Duvaut-Lions format are nearly consistent. In contrast， those calculated by the nonlinear visco-damage models with Perzyna format and Duvaut-Lions format differ. In addition， the improvement in dynamic strength predicted by both nonlinear models agrees well with test data， indicating that both can reflect the rate sensitivity of concrete material.