利用无粘结预应力技术进行超长混凝土结构的裂缝控制-道路与铁道工程专业论文.docxVIP

摘要本文立足于有关的工程背景，从解决(控制)超长结构的温度及收缩裂缝的角度 摘要 本文立足于有关的工程背景，从解决(控制)超长结构的温度及收缩裂缝的角度 出发，全面系统地论述了用无粘结预应力技术解决超长问题的基本原理、定性分析、 定量计算方法的有关问题。从一个方面解决了工程实际问题。主要内容有： (1)简述了工程结构裂缝的概念、成因，讨论了混凝土结构计算温度场的确定原则 和方法； (z)简述了温度应力的基本概念，详细讨论了各种约束条件下的温度应力计算方法， 推导了相应的计算公式： (3)讨论了混凝土收缩简化计算方法及混凝土徐变对温度及收缩应力计算的影响； (4)探讨了预应力解决超长问题的基本原理，给出相应的裂缝控制验算公式和标准， 详细讨论了各种约柬条件下的有效预压应力计算方法。推导了相应的计算公式； (5)讨论了弯曲超长结构预应力作用下的整体弯曲效应的计算方法，对洞口问题的 受力原理及解决途径进行了详细的探讨，同时讨论了与本问题相关的其它问题； (6)通过两个有代表性的工程实例的有限元分析，对本文的理论分析作了全面系统 的总结。 【关键词】超长结构无粘结预应力计算温度场混凝十收缩约束条件温度应力髹 2、 变有效预压应力整体弯曲效应渝审有限元分析 ／、 ABSTRACTFrom ABSTRACT From the point of view to solve(contr01)the shrinkage and temperature crack of extra-long concrete structures，this paper,based on relevant engineer backgrounds， comprehensively and systematically discusses the crack-resistant questions of extra--long concrete structures with unbonded prestressed technology,including basic principle， qualitative analysis，quantification calculation，and so on，and solves the practical engineering problem in this regard aspect．The main points are as follow： 1．The paper discusses the concept and cause of construction cracks，and the principle and method on the establishment of calculation temperature field． 2．After narrating the basic concept of temperature stress，the calculation methods of temperature stress under various constraint conditions are presented in detail，and the relevant calculation formulae are derived． 3．The paper studies the simplification calculation method of concrete shrinkage and the calculation of temperature and shrinkage stress that takes the effects of concrete creep into account． 4．The paper probes into basic principles of extra—long problem using unbonded prestressed technology,and gives relevant formulae and standard of crack control，and researches in detail calculation methods of effective prestress under various constraint conditions，and derives relevant calculation formulae． 5 The calculation method of overall bending effect on flexure extra-long construction is