ABAQUS混凝土损伤塑性模型中损伤因子的率相关性及实现方法

ABAQUS程序中最常用的混凝土损伤塑性（concrete damage plasticity, CDP）模型无法实现损伤因子与应变率相关。为了准确描述混凝土材料在高应变率下的损伤特性，基于CDP模型定义了新的应变率场变量，编制了VUSDFLD用户子程序，开发了能够考虑损伤因子率相关性的改进的CDP（modified CDP，MCDP）模型。MCDP模型采用能量法求解混凝土拉压损伤因子，主求解程序能够随着应变率场变量的变化而自动更新不同应变率对应的损伤参数，计算得到的混凝土单轴静态加载结果与CDP模型吻合较好。MCDP模型对高应变率下动态压缩性能的模拟结果表明:混凝土材料在不同应变率下的拉压损伤对其动态力学性能有显著影响，编制的VUSDFLD子程序和MCDP模型能够有效地解决损伤应变率相关的模拟难题，可以准确地模拟爆炸荷载作用下钢筋混凝土梁的动态响应，为预测爆炸冲击等强动载作用下混凝土结构的响应和破坏提供了更可靠的技术途径。

Rate correlation of the ABAQUS damage parameter in the concrete damage plasticity model and its realization method

The concrete damage plasticity (CDP) model, as commonly adopted in ABAQUS routine, fails to correlate damage parameters with strain rate. To accurately describe the damage of concrete under high strain rate, a modified CDP (MCDP) model considering the rate correlation of damage parameters was developed by defining a new strain rate field variable and compiling VUSDFLD subroutine. In the MCDP model, the tensile and compressive damage parameters can be obtained by the energy method, and the main solver can automatically update the damage parameters under different strain rates with the change of strain rate field variables. Under static load, the results calculated by the MCDP model are in good agreement with those by the CDP model. The MCDP model was then used to calculate the dynamic compression performance of concrete under high strain rate, indicating that the tensile and compressive damage parameters of concrete under different strain rates have a significant influence on its dynamic mechanical properties. The compiled VUSDFLD subroutine and the MCDP model can solve the problem of the correlation between damage and strain rate, investigate the dynamic response of reinforced concrete beams accurately, and provide a more reliable technical way in predicting the response and destruction of the concrete structures under severe dynamic loading such as explosion and impact.