摘要
针对Giuffre-Menegotto-Pinto钢筋滞回本构模型(MP模型)发生小幅卸载再加载履历(小幅循环)时存在应变和刚度突变、高估材料强度缺陷的问题,通过定义钢筋材料的弹性域半径引入新的小幅循环判别方法,将小幅循环分为2种类型,提出对小幅反转点重新赋值的修正方法,消除不合理的履历;应用修正后的MP模型和Mander混凝土模型,开发基于空间纤维梁单元理论的RC结构弹塑性分析程序;分析含小幅循环的钢筋滞回曲线、模拟RC柱的拟静力试验结果,检验修正方法的有效性.结果表明:修正的MP模型发生小幅循环时履历合理,避免了原模型刚度和应力偏大的问题;修正模型改进了RC结构中钢筋在地震作用下的滞回履历,在弹塑性分析中有较好的计算效率.
The Giuffre-Menegotto-Pinto constitutive model of reinforcement(MP model)will develop an unrealistic sudden change of the strain and stiffness,and overestimate the stress under a circumstance of reloading subsequent to a small-amplitude unloading history.The definition of the elastic range radius and the reassignment of reversal points were proposed to overcome the defect of MP model.The criterion of small strain vibration was determined and divided into two different cases based on the radius of elastic range.A nonlinear analysis program of the reinforced concrete structure was developed based on the fiber beam element,in which the modified MP model and the Mander concrete model were included.The accuracy and applicability of the improved method were verified by both the analysis of steel bar’s hysteresis characteristic under small strain vibration and the simulation of the loaddisplacement curve for a pier through pseudo-static test.Results show that the stress-strain curve predicted by the modified MP model is more rational,and the overestimation of the horizontal bearing capacity and the stiffness of structures can be successfully avoided.The accuracy of hysteretic curve of reinforcement was significantly improved by the modified model in the reinforced concrete structural elasto-plastic analysis.
作者
雷燕云
谢旭
LEI Yan-yun;XIE Xu(College of Civil Engineering and Architecture,Zhejiang University,Hangzhou 310058,China)
出处
《浙江大学学报（工学版）》
EI
CAS
CSCD
北大核心
2018年第10期1926-1934,共9页
Journal of Zhejiang University：Engineering Science
基金
国家自然科学基金资助项目(51378460)
作者简介
雷燕云(1992—),女,硕士生,从事桥梁抗震研究.orcid.org/0000-0003-2929-4869.E-mail:21512077@zju.edu.cn;通信联系人:谢旭,男,教授.orcid.org/0000-0002-4247-0487.E-mail:xiexu@zju.edu.cn。
