预应力混凝土梁徐变挠度影响因素分析与计算模式构建*
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（1 许昌学院土木工程学院， 许昌 461000； 2 郑州大学水利与环境学院， 郑州 450001）
［摘要］准确计算预应力混凝土桥梁的徐变挠度对预控其长期挠度非常重要。对当前混凝土梁的几种徐变挠度计算方法进行对比分析，并以预应力混凝土梁徐变挠度系数与徐变系数关系为研究对象，分析了预应力度、预应力产生的轴力、预应力产生的等效弯矩、构件换算截面面积及构件截面抗弯模量等因素对徐变挠度系数与徐变系数间关系的影响及规律。结果表明：在已知徐变系数的情况下，梁的预应力度对徐变挠度系数的影响较大，而其他几种因素对该系数影响较小；进一步建立了便于工程应用的、考虑预应力度和混凝土徐变共同影响的预应力混凝土梁徐变挠度计算模式，为精确预控预应力桥梁结构的长期挠度奠定基础。［关键词］预应力混凝土梁; 徐变挠度; 徐变系数; 影响因素; 计算模式中图分类号：TU378.1 文献标识码：A 文章编号：1002-848X(2016)06-0095-05
Analysis of influencing factors of creep deflection of prestressed concrete beams and construction of the calculating modelWang Jun1,2, Wang Bo2, Kong Yamei1(1 Department of Civil Engineering , Xuchang University, Xuchang 461000, China; 2 College of Water Conservancy & Environment Engineering, Zhengzhou University, Zhengzhou 450001, China)Abstract: It is important to precisely calculate the creep deflection of pre-stressed concrete bridges for pre-controlling the long-term deflection. After comparing a number of existing creep deflection models, and analyzing the numerical relationship between creep deflection coefficient and creep coefficient moreover, it is found that the influencing factors of the model such as prestress degree, axial compression and moment due to prestress, equivalent section area, and section modulus of bending, etc. The results show that: under known creep coefficient, the creep deflection coefficient is impacted mostly by prestress degree, but less by other factors. Finally, a simplified creep deflection formula is derived to better pre-control the long-term deflection of prestressed bridges and is easier to apply into practice.Keywords:prestressed concrete beam; creep deflection; creep coefficient; influencing factors; calculation model
*中国博士后科学基金资助项目（2014M562000），河南省高等学校青年骨干教师资助项目（2014GGJS-118），河南省高等学校重点项目（15A560009）。作者简介：王俊，博士，副教授，郑州大学水利工程博士后流动站博士后, Email：wangjun7512@sina.com。
