箍筋约束ECC力学性能及应力-应变模型研究

项目名称： 箍筋约束ECC力学性能及应力-应变模型研究

项目编号： No.51208183

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 建筑环境与结构工程学科

项目作者： 李艳

作者单位： 河南理工大学

项目金额： 25万元

中文摘要： ECC材料具有高强度、高延展性、高耐久性和可持续性，可显著改善混凝土结构的抗震性能和抗剪性能。箍筋约束ECC力学性能的研究与应力-应变模型的建立是进一步研究ECC构件、结构抗震性能的基础与前提。基于微观力学的ECC设计参数分析，研制满足高强度高延性的ECC材料，通过ECC材料基本力学性能的研究，建立ECC基本力学指标；通过箍筋约束ECC柱的轴压性能试验研究与有限元分析，揭示箍筋约束ECC柱的受力规律和破坏机理，建立箍筋横向约束应力的计算方法，构建基于配箍特征值、PVA纤维体积掺量等主要影响参数的峰值应力、峰值应变和极限应变的计算模型，提出可嵌入有限元分析程序中的ECC单轴受拉、受压本构模型及箍筋约束ECC的应力-应变计算模型，为进一步研究ECC构件、结构的抗震性能提供依据。

中文关键词： ECC；箍筋约束；力学性能；应力-应变关系；有效约束

英文摘要： ECC has high strength, high ductility, high durability and sustainability. It can significantly improve the antiseismic performance and shear behavior of concrete structure. For further studying on antiseismic performance of ECC members, it is essential to study mechanical behavior and to establish stress-strain model on ECC confined by stirrups. By analyzing the micro-mechanical model, ECC with high strength and high toughness are prepared. The mechanical parameters of ECC are established by the study on mechanical performance. According to the experimental study and finite element analysis of ECC columns confined by stirrups, mechanical behavior and failure mechanism are indicated. The calculating method of lateral constraint stress of stirrups is established. By considering the confining reinforcement characteristic value and PVA fiber volume content, the computational models of peak stress, peak strain and ultimate strains are proposed. The stress-strain models of ECC on uniaxial tension, uniaxial compression and stirrups confined are built, which can be embedded in the finite element program. This provides a basis for further study on seismic performance of ECC structure.

英文关键词： ECC；stirrups restraints；mechanical behavior；stress-strain relationship；effective restraint