大体积混凝土水化热分析及温度控制措施

发布时间：2018-03-06 04:27

本文选题：大体积混凝土　切入点：水化热　出处：《长沙理工大学》2014年硕士论文　论文类型：学位论文

【摘要】：近年来,桥梁工程中的大体积混凝土结构也应用越来越广泛。大体积混凝土结构因为尺寸较大,从混凝土浇筑到混凝土凝固这段时间,水泥发生的水化反应所产生的热量不容易散发且加上混凝土的自身的特点与外界条件等情况,容易使结构内产生较大的拉应力,从而导致结构产生裂缝。本文在总结国内外学者研究成果的基础上,对大体积混凝土水化热进行分析及对温度控制措施的相关因素进行研究,以对类似工程提供参考。本文的主要工作内容有：(1)本文介绍了大体积混凝土结构的定义、特点、桥梁工程上的应用已经国内外的研究现状；并从大体积混凝土的热传导理论出发,对温度场的有限元计算进行了理论推导,同时混凝土材料各因素对于水化热的影响进行介绍,最后对于控制混凝土的绝热温升提供参考意见。(2)通过总结学者的研究成果,从精心设计、合理的方法优化混凝土的配合比、选择合适的施工方法、采取有效的控温措施以及混凝土结构的表面保温措施等方面的共同作用下才能够更好地控制大体积混凝土的内部温度,更好的预防大体积混凝土产生裂缝。(3)利用MIDAS CIVIL有限元软件对赫章特大桥混凝土承台的水化热和温度控制进行研究分析,并对其实测温度进行对比研究分析,得到结果吻合较好。这说明通过有限元建模对于模拟分析承台的效果较好。(4)本文还在此基础上对分层浇筑块法进行了研究分析,得到了其方法对防止温度裂缝的产生也是行之有效的。同时还对水管冷却方式的各个因素进行对比总结,得到水管冷却各参数对于温控的规律,并对温控合理规划设计,防止裂缝产生。
[Abstract]:In recent years, mass concrete structures in bridge engineering have been used more and more widely. The heat produced by the hydration reaction of cement is not easy to emit, and the characteristics of concrete and the external conditions, etc., which make the tensile stress in the structure easy to be produced. On the basis of summarizing the research results of domestic and foreign scholars, this paper analyzes the hydration heat of mass concrete and studies the relevant factors of temperature control measures. This paper introduces the definition and characteristics of mass concrete structure, and the application of bridge engineering has been studied at home and abroad. Based on the heat conduction theory of mass concrete, the finite element calculation of temperature field is theoretically deduced. At the same time, the influence of various factors of concrete material on hydration heat is introduced. Finally, for the control of adiabatic temperature rise of concrete to provide reference advice. 2) through summing up the research results of scholars, from careful design, reasonable method to optimize the mix ratio of concrete, select the appropriate construction method, Under the joint action of effective temperature control measures and surface insulation measures of concrete structure, the internal temperature of mass concrete can be better controlled. Using MIDAS CIVIL finite element software, the hydration heat and temperature control of concrete cap of Hezhang super bridge are studied and analyzed, and the measured temperature is compared and analyzed. The results are in good agreement with each other. This shows that the finite element modeling is better for simulating and analyzing the cap.) on this basis, the layered pouring block method is also studied and analyzed in this paper. The method is also effective to prevent temperature cracks. At the same time, the factors of water pipe cooling mode are compared and summarized, and the rules of water pipe cooling parameters for temperature control are obtained, and the reasonable planning and design of temperature control are obtained. Prevent cracks from occurring.
【学位授予单位】：长沙理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U445.57

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