建筑工程大体积混凝土裂缝控制与应用范德均.docx

1、建筑工程大体积混凝土裂缝控制与应用范德均重庆大学工程硕士学位论文建筑工程大体积混凝土裂缝控制与应用硕士研究生：范德均指 导 教 师 ：张宏胜 副教授兼 职 导 师 ：杨树永 高 工工 程 领 域 ：建筑与土木工程重庆大学土木工程学院二 OO 六年十月A Thesis Submitted to Chongqing Universityfor the Engineering Master DegreeConstruction Engineering Mass ConcreteCrack control and ApplicationCandidate: Fan DejunSupervisor: A

2、. Prof. Zhang HongshengPluralistic Supervisor: Senior Engineering Yang ShuyongSpecialty: Construction and Civil EngineeringCollege of Civil EngineeringChongqing UniversityOct. 2006重庆大学硕士学位论文 中文摘要I摘 要大体积混凝土开裂后，其性能与原状混凝土性能差异很大，尤其是对耐久性(渗透性)的影响更大；混凝土渗透反过来又会加速和促使混凝土的进一步恶化，严重影响其结构的长期安全和耐久运行。裂缝的产生大多在早期，因此，

3、探讨裂缝产生的原因以防止裂缝的出现就显得格外重要。本文首先讨论了大体积混凝土的定义，建筑工程大体积混凝土的特点，温度及产生温度应力的条件，综述了大体积混凝土裂缝控制的研究现状。其次探讨了裂缝产生的机理和大体积混凝土温度裂缝的成因及影响因素，概述了控制大体积混凝土裂缝的原理(方法)是提高混凝土的抗裂能力和控制温度应力。提高混凝土抗裂能力的一般方法是：掺膨胀剂，掺增强材料，配温度筋，提高混凝土的强度。控制温度应力的方法是：减少水泥用量，使用低热水泥，降低浇筑温度，降低混凝土的干缩(即当量温度)，强制降温,减少外部约束和减少内部约束。然后分析了大体积混凝土温度的变化过程，温度应力的发展过程及温度应力

4、的类型。给出了大体积混凝土的各种温度计算方法以及温度应力的计算方法。大体积混凝土裂缝产生是由多种因素造成的，设计的合理性，材料的优选及配合比确定，尤其是施工技术和施工方案的正确确定，是防止大体积混凝土裂缝的有效措施。具有十分重要的工程意义。本文研究的重点是如何配制高强度大体积混凝土。采用了“三掺技术”，即在大体积混凝土中掺入 U 型膨胀剂，粉煤灰和减水剂，充分利用它们各自的优点，相互补充。并采用科学的施工工艺及合理的混凝土养护措施来控制裂缝，防止渗漏。从而保证了大体积混凝土的施工质量。最后结合工程实例，拟定了合理的施工方案及技术措施。根据实际情况和试验资料，水泥采用江油产 42.5 级普通硅酸

5、盐水泥，掺入缓凝减水剂 LFS、UEA 膨胀剂、粉煤灰。为有效控制大体积混凝土开裂，在中部设置两层双向 14200 的温度筋，设置温度筋，提高配筋率，充分发挥了 UEA 的限制膨胀。同时分散应力，提高了抗裂性。采用了合理的保温、保湿养护工作，并对施工过程中做了温度全程监测。即时调整养护措施，确保了工程质量，施工完毕，混凝土的一切性状皆达到了预期效果。关键词：大体积混凝土，温度裂缝，三掺技术，实际应用重庆大学硕士学位论文 英文摘要IIABSTRACTComparing with the original, the property, especially the durability would

6、 beheavily affected when cracks appear in “Massive Volume Concrete.” On the other hand,the Seepage of the concrete would also accelerate the deterioration of the concrete, andput evil forth on the long-term safety and durability of it. It is essential to discuss thecause of the cracks in order to pr

7、event the occurrence of it in that most of the cracks inorder to prevent the occurrence of it in that most of the cracks appear in the prior stageof the construction.Firstly, this essay has discussed the definition of “Massive Volume Concrete” inarchitectural project, the temperature and condition f

8、or cawing “Temperatural Press”. Ithas also generally described the present research condition in the control of “MassiveVolume Concrete Cracks”.Secondly, it has discussed the mechanical reasons in the forming of cracks and thecause of “Temperatural cracks” in “Massive Volume Concrete”. It pointed ou

9、t the wayof controlling “Massive Volume Concrete Cracks” is to improve the “anti-cracking” and“temperatural press-controlling” competence. The general way for improving theanti-cracking competence is; putting leavening agent Adding reinforcing material Matching temperatural Steel in order to enhance

10、 the strength of the Concrete. And,the way for controlling the temperatural press is; Reducing the use of cement Using low-heated cement Cutting down the pouring temperature in construction. Reducing the difference between temperature in construction and force the temperaturedown, if necessary, in o

11、rder to reduce the restriction from both the out and inner space.Then it has analyzed the changing course of the temperature in “Massive VolumeConcrete”, and the course of the development and category of the “temperatural press”.It has also suggested the way of counting different kinds of temperatur

12、e andtemperatural press in “Massive Volume Concrete”The reason of the occurrence in “Massive Volume Concrete Cracks” is complicated:the rationality of the design, the sensibility in the choose of materials, the decision ofthe matching proportion, especially the accurate choose of the constructing te

13、chnologyand plan are effective measures to prevent “Massive Volume Concrete Cracks”. All ofthem have crucial importance in architectural field.The main research point in the essay is to discuss how to make “Massive Volume重庆大学硕士学位论文 英文摘要IIIConcrete” which is high in strength. In order to achieve this

14、, “Three permeatedtechnology” is applied - that is to add coal ash in “Massive Volume Concrete” andmake full use of their advantage to compensate from each other. Whats more, it hasapplied the scientific constructing technology and proper protecting measure to controlthe cracks in order to prevent s

15、eepage so as to assure the quality in construction.In the end, connected with instances, it puts out the applicable architectural methodand measure in construction. According to the actural cases and experimental materials,it applied the ordinary cement which permeated with “Water Reducing Moderator

16、 LFS”“Leavening Agent LEA” and “Coal Ash” made in Jiangyon, Sichuan Province. In orderto control the cracks in “Massive Volume Concrete” effectively, tempratural steel whichhad double faces and directions was put in the middle of it in order to improve thematching proportion of the steel and make fu

17、ll use of the restricted expansion of theVEA. At the same time, the press was distracted so as to improve the anti-crackingcompetence of the concrete. The application of the proper wet-protecting task was alsodone. Whats more, an close examination has done during the whole course of theconstruction.

18、 The pretty adaption of the protecting measure assured the quality of theproject. All the characters reached to the expected state when the construction had beenfinished.Key words: Massive Volume Concrete, Temperatural Cracks, Three PermeatedTechnology, application重庆大学硕士学位论文 目 录IV中文摘要.I英文摘要.II1 绪论.

19、11.1 大体积混凝土的定义. 11.2 建筑工程大体积混凝土的特点. 11.3 温度及产生温度应力的条件. 21.4 裂缝与裂缝控制的概念. 31.5 研究现状. 31.6 本文研究内容. 52 裂缝产生的机理和大体积混凝土温度裂缝的成因和影响因素. 62.1 大体积混凝土结构裂缝产生的机理 . 62.2 大体积混凝土温度裂缝的特点. 102.3 控制大体积混凝土裂缝的原理(方法)分析 . 102.4 混凝土结构裂缝的限制与修补. 143 大体积混凝土的温度场与温度应力的计算 . 153.1 大体积混凝土温度的变化过程. 153.2 混凝土温度应力的发展过程及温度应力的类型 . 153.3

20、大体积混凝土的混凝土拌合物温度 . 163.4 水泥水化热与混凝土绝热温升. 173.5 大体积混凝土的温度应力计算. 183.6 控制温度应力，防止裂缝的措施. 204 大体积混凝土施工方案和施工技术研究. 224.1 大体积混凝土的设计构造要求. 224.2 混凝土配合比及其材料. 234.3 混凝土的浇筑与养护. 254.4 大体积混凝土“后浇带”的设计与施工 . 274.5 大体积混凝土的冬期施工. 295 “三掺”技术在大体积混凝土中试验研究 . 325.1 试验研究的目的. 325.2 减水剂、膨胀剂、粉煤灰的性能. 325.3 “三掺”混凝土的配合比设计及试配 . 34重庆大学硕士学位论文 目 录V5.4 试验结果 . 365.5 试验结果分析 . 395.6 小结 . 436 大体积混凝土施工实例 . 446.1 工程概况 . 446.2 施工方案及技术措施 . 446.3 本工程的温度应力预控计算 .