【作者】 朱国忠；

【导师】 吴胜兴；

【作者基本信息】 河海大学 ， 结构工程， 2005， 硕士

【摘要】 砌体结构是目前我国住宅建筑的主要结构形式之一，温度裂缝问题是其常见而又亟待解决的问题，基于此，本文对砌体结构温度场进行了现场实测与仿真分析、探讨了砌体结构温度应力计算方法，并在此基础上研究了基于温度效应的砌体结构抗裂概念设计方法。 国内外专家、学者对砌体结构的温度裂缝问题进行了大量的科学研究，提出了不同观点，但基本上仅局限于砌体结构温度裂缝的定性分析，还缺乏深入系统的研究，主要体现在以下几个方面；(1)对砌体结构的温度作用缺乏必要的、足够的现场实测资料；(2)温度应力的计算理论还不完善，剪应力法、放松法等温度应力的简化计算方法均存在一定的局限性；(3)国内至今仍没有一套关于砌体结构温度裂缝计算及其构造的规范化要求，《砌体结构设计规范》(GB50003-2001)关于砌体结构的抗裂措施也存在一定的局限性。 本文主要进行了以下几个方面的工作：(1)探讨了砌体结构温度裂缝的产生机理，总结归纳了常见砌体结构温度裂缝类型；(2)对砌体结构墙体与屋面板的温度场进行了现场实测；(3)对砌体结构温度场进行了仿真分析，并与实测数据进行了对比分析；(4)研究了砌体结构温度应力的有限元计算方法；(5)针对一工程实例，计算分析了其温度应力分布规律和特点；(6)砌体结构的温度应力不仅与温度有关，还与结构的约束程度、结构的型式、尺寸等因素有关；(7)从材料、构造措施、施工等几个方面出发，研究了基于温度效应的砌体建筑的抗裂结构概念设计方法。 在上述研究工作基础上得到了一些重要成果：(1)得到了砌体结构墙体与屋面板随时间的温度场变化规律，温度场的仿真分析结果与实测结果在趋势上一致：(2)设置保温隔热层时，混凝土屋面板沿厚度方向温度变化较小，不设时较大；(3)温度裂缝的出现位置可根据结构温度应力的分布图来判断。当升温膨胀时结构顶层端部的剪应力较大，最易发生裂缝；在纵墙中部的水平正应力σ_x较大，此处时有通长裂缝产生。屋面板四周和纵墙端部两开间顶上两层、山墙或是端部开间门窗洞口角部的拉应力均较大，顶层墙体和边部内、横纵墙与圈梁的接触面上的剪应力较大，在这些部位容易产生裂缝；(4)基于温度效应的砌体建筑的抗裂结构概念设计方法可有效地控制砌体结构的开裂。本文关于砌体结构的研究成果可对砌体结构设计和分析研究提供借鉴与参考。更多还原

【Abstract】 Masonry structure is one of the most important forms of residential buildings in China. The common and urgent to be solved problem for this kind of structures is temperature cracks. The objective of this paper is to do the observation and simulation of the temperature field and to study, the calculation method of the temperature stress of masonry structure. Furthemore, the conceptualized anti-crack design method of masonry structure based on temperature effect is discussed.A lot of studies have been done on cracks of masonry structure both in and outside China. There is no systematic research in this field up to date. Different opinions have been proposed focusing on qualitative analysis of temperature cracks. The present situation in this area can be summarized as follows: (l)There are not enough observation data on temperature field.(2)Temperature stress calculation theories are premature.(3)Furthermore, methods of controlling the temperature cracks in masonry structure are incomprehensive, including those proposals in’ Masonry Structure Design Criterion ’(GB50001-2001).The main work presented in this paper includes:(l)The mechanism and types of temperature cracks in masonry structure have been studied .(2) The temperature field of the wall and roof of a masonry structure has been observed.(3)The temperature field of a masonry structure has been simulated with a computer program and the results are compared with the observation data.(4)The FEM of temperature stress has been studied.(5)The distribution rule and the characteristics of temperature stress in a masonry structure have been discussed based on a real project.(6)Temperature stress in masonry structure is influenced by many factors, such as temperature, restriction degree of the structure, structural patterns and dimension, and etc.(7)The conceptualized anti-crack design method of masonry structure has been put forward based on material, constructional measures and construction techniques.On the basis of the researches mentioned above, the following important results are obtained:(l)The rule of variation of temperature field with time in wall and roof of a masonry structure have been obtained, and the result of the temperature field simulation is consistent with test data.(2)The difference of temperature along thickness in concrete roof with heat preservation layers changes less than that without heat preservation layers. (3)The places of the temperature cracks can be forecasted on the basis of the stress charts. The draught stress is bigger at the roof circumambience, the walls of the end two rooms of the top two floors, the east and west walls, and the hole corners of the doors or windows. The shear stress is larger at the interfaces of the top walls and the end interior walls. The above conclusion is consistent with the fact and the temperature cracks may emerge there (4) The temperature cracks can be effectively controlled based on the conceptualized anti-crack design method of masonry structure. The conclusions about masonry structure drawn in this paper can provide reference for design and analysis of masonry structure.更多还原