结构消(耗)能元件芯材SN490B本构关系数值模拟

采用消(耗)能元件的结构在遭受地震作用时,元件芯材首先屈服进入塑性阶段,利用其滞回变形消耗地震输入能量,保护主体结构,元件芯材本构关系的数值模拟是对采用消(耗)能元件结构进行抗震分析与设计的基础。为更真实地模拟结构消(耗)能元件芯材在单调和循环荷载下的本构响应,更准确地对采用消(耗)能元件结构进行结构弹塑性地震响应分析,对常用作消(耗)能元件芯材的日本高延性钢材SN490B的单调、循环加载本构及循环骨架曲线进行了数值模拟,包括:采用Esmaeily-Xiao二次流塑性模型模拟材料在单调荷载作用下弹性段、屈服段、强化段和二次流塑段4个阶段;采用混合强化模型模拟材料循环荷载作用下的本构响应,运用大型通用有限元软件ABAQUS结合数值模拟参数对16种不同循环加载制度下的循环加载试验进行模拟,并与试验结果进行对比;采用Ramberg-Osgood模型、无量纲化的Ramberg-Osgood模型及两段式模型模拟循环骨架曲线。研究结果表明:所采用数学模型可以较好地模拟SN490B钢材单调、循环加载本构响应及循环骨架曲线,数值模拟与试验结果拟合较好。

Numerical simulation of constitutive relation of core material SN490B used in energy dissipation device

When structure using energy dissipating device suffers from earthquake, its core materials will first go into the plastic yield stage and consume earthquake input energy by hysteretic deformation to protect the main structure. Therefore, the numerical simulation of core materials constitutive relation is the basis of seismic analysis and design with dissipation device. Theconstitutive relation of energy dissipation device under monotonic loading and cyclic loading elastic-plastic seismic response of the structure with energy dissipation device were investigated in the numerical simulation of monotonic constitutive relation, cyclic constitutive relation and skeleton curve of SN490B steel. The simulations include the four stages which are elastic stage, collapse stage, strain-hardening stage and secondary flow plastic stage of core material using Esmaeily-Xiao secondary flow plasticity model; the constitutive response of core materials under cyclic loading using combined hardening; the skeleton curve using the Ramberg-Osgood model, dimensionless Ramberg-Osgood skeleton curve model and double-linear model. Based on finite element software ABAQUS combined with numerical simulation parameters, numerical simulation of 16 different cyclic loading tests was conducted and compared with the test results. The results show that: mathematical model can be used to simulate the monotonic constitutive response, cyclic constitutive response and cyclic skeleton curve of SN490B steel accurately. Numerical simulation and experimental results fit well.