混凝土早龄期收缩变形与应力发展规律研究

项目名称： 混凝土早龄期收缩变形与应力发展规律研究

项目编号： No.51279017

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 水利工程

项目作者： 杨华全

作者单位： 长江水利委员会长江科学院

项目金额： 79万元

中文摘要： 裂缝问题是影响工程质量和耐久性的关键因素之一。伴随水工结构型式复杂化、材料多元化以及服役环境多样化的发展趋势，混凝土早龄期裂缝日益严峻，严重的还会危及工程安全，缩短工程寿命。受传统试验方法与测试技术限制，难以对约束条件下混凝土早龄期裂缝发展演变规律进行量化表征。本项目从温度-应力的角度，围绕混凝土早龄期裂缝发生、发展及控制等方面，探明混凝土早龄期收缩变形特性、热学性能及内应力的发展规律，分析混凝土内部温升与温度应力的发展趋势，建立混凝土早龄期拉伸徐变模型；综合考虑约束程度、环境条件、材料组成等因素，研究混凝土早龄期收缩变形与温度变形产生的累积应力及对混凝土本身带来的损伤特征，建立了水工大体积混凝土开裂的风险评估机制，为我国现代大体积混凝土结构防裂和限裂处理以及设计、施工和运行提供科学依据和源头技术支持。

中文关键词： 混凝土；裂缝；早龄期；约束；变形

英文摘要： Concrete crack is one of key factors to affect engineering quality and durability. With the compliction of hydraulic structure design, and the diversification of materials and the service environment, the concrete crack at early age has become increasingly severe, which influences the security and lifetime of projects. Limited by traditional test methods and techniques,it is difficult to quantitively reflect the early-age cracking of concrete. From the angle of the correlation of temperature and stress,this item investigates the occurrence, development and control of the early-age cracks of concrete. The early-age shrinkage, thermal properties and the internal stress development of concrete are also explored. The internal temperature rise and temperature stress of concrete are studied to establish the early-age tensile and creep model of concrete. With the consideration of such factors as confinements, environmental conditions, material composition and so on, the accumulated stress caused by the early-age shrinkage and temperature deformation of concrete, as well as its effect on concrete demage, are studied to establish the risk evaluation mechanism for the cracking of hydraulic mass concrete. This item provides scientific basis and technical support for the anti-cracking treatment and related design, construct

英文关键词： concrete；crack；early age；constraint；deformation