【作者】 张忠；

【导师】 陈志华；

【作者基本信息】 天津大学 ， 结构工程， 2012， 博士

【摘要】 核电站基础是反应堆厂房主要支撑结构，一方面建于沿海地区，受到海水侵蚀，另一方面也是防止核泄露，因此对其施工裂缝控制要求很严。核电站基础浇筑量大、混凝土强度高、水化热大，核电站混凝土特殊性能使得施工常规降低水化热措施无法使用，国内外一直采用分层分段小体量多次浇筑的施工方式，施工周期长并且均不可避免的出现了较多裂缝，处理裂缝对施工进度也造成了一定影响。随着核电市场的急剧扩张及减少施工层段数对总体工期缩短的明显有利作用，实施多层段合并为一次整体性浇筑，温度裂缝能否得到有效控制成为当前的一大尖锐课题。本文提出了多层段合并为整体浇筑的可行性问题并开展以有限单元法理论为基础的大体积混凝土温度及温度应力应变场分析和测试研究，试图揭示大体积混凝土温度应力发生、发展规律，为指导混凝土施工养护、裂缝控制提供基本理论依据。课题基于理论分析与测试比较，通过编制有限元分析程序，建立和优化基础整体有限单元模型，对整浇全程进行深入全面的仿真分析，研究了基础不同浇筑厚度、垫层不同滑动能力、不同养护方式及技术指标对施工温度应力的影响，验证了实施多层整体浇筑的可行性与优越性、防水层兼做滑动层的必要性、动态有差别施工养护方式和技术指标对于调整温度应力场及降低混凝土开裂风险的重要性。同时课题还对混凝土的收缩进行了较全面的研究，研制了混凝土的无约束监测装置，对核电特定配合比混凝土的收缩进行监测和分析。总之，课题提出了“动态设计养护法”，给出了大体积混凝土施工裂缝控制一类问题的一般处理思路和方法，为科学制定和优化设计施工方案提供基本依据。实践表明，本研究方法进行的理论分析及其指导下的大体积混凝土施工，开拓了设计施工技术空间，保证了混凝土浇筑质量，赢得了工期和积累了经验，为后续我国核电几十台机组基础混凝土整体浇筑成功实践和推广应用奠定了坚实基础，为国民经济建设创造了相当可观的经济和社会效益。更多还原

【Abstract】 The base slab of the reactor building is one of the main support parts， which iscorroded by seawater in the coastal areas and is needed to prevent nuclear leakage，so it’s extremely strict about crack for the durability and tightness. Bulky pouring，high concrete strength and large heat of hydration make it difficult to controlconstruction cracks. At the foreign and domestic nuclear plants delamination orsubregion had been adopted normally for mass concrete construction， but theconstruction period extended and still had more serious cracks appeared， which hadpaid great costs to deal with them. With the rapid expansion of the nuclear powermarket and shorten the overall period， the merge concreting which can bring muchhigh benefit should be studied.This paper presents it is feasible to the merge concreting with multi-layersegment， and carry out the theoretical analysis and testing of mass concretetemperature and temperature stress-strain field under the guidance of the finiteelement method. Through compiling the finite element software and establishingmodel， the simulation analysis about the impact of different pouring thickness，different sliding ability， different conservation methods and technical indicators toconstruction temperature stress has been done. The results proved that the mergeconcreting is superior， waterproof layer acting as sliding layer is necessary，dynamic and differential construction curing methods are important to adjust thetemperature stress field and reduce the risk of cracking. At the same time， the papercarries out a comprehensive study of the shrinkage， and a unconstrained device forconcrete is developed for monitoring the free deformation in different curing methods.In short，the subject puts forward the dynamic design curing methods which givethe general ideas for construction crack control of mass concrete and can provide thehelp for optimizing and designing construction program. Practice has proved thatunder the theoretical system the base slab merge concreting of dozens China’s nuclearplant reach success. All these have created considerable economic and social benefitsfor our National economy.更多还原