文档介绍：华中科技大学
硕士学位论文
某超长预应力混凝土框架结构裂缝成因分析
姓名:孟凌
申请学位级别:硕士
专业:结构工程
指导教师:张耀庭
20080604
摘要
随着国民建设的发展我国大型公用建筑基于功能和外观上的需要,建筑师往往希
望在建筑设计中不设或者少设伸缩缝,致使整个结构长 100m 以上、平面面积 10000m2
以上,我们称这类结构为超长框架结构。这类结构在荷载、环境温度变化、基础不
均匀沉降等外在变形因素,混凝土收缩等内在变形因素共同作用下常常会出现裂缝。
一般来说对于“表面性”裂缝,采用适当的修补和装修措施是可以妥善解决的;而“结
构性”裂缝既是一个古老的工程质量难题,又是一个值得深入研究的新问题,有必要
对其产生机理、影响因素和数值仿真进行系统研究。
本文的主要研究目的是通过研究北京首都国际机场 2 号航站楼前停车楼主体结
构中出现的裂缝问题,参考武汉港湾工程质量检测中心对该停车楼结构裂缝检测报
告和安全性评估报告,并利用常用有限元软件对该超长框架结构进行数值模拟,研
究该类结构在不同效应共同作用下裂缝产生的机理。
以结构裂缝检测和安全性评估报告为基础对该楼在正常使用期季节温差和混凝
土收缩及停车楼地上一层在车辆荷载作用下进行了有限元分析,计算结果表明造成
该停车楼裂缝开展的主要原因为季节温差下的温度应力和混凝土的收缩,局部楼层
的裂缝开展严重的原因则是设计时选取楼板活荷载设计值与实际受力不符而导致结
构构件承载力不足。
关键词:超长框架,裂缝,温度应力,混凝土收缩,有限元分析
I
Abstract
The ultra-long reinforced concrete frame structure often cracks when it is applied by
the external factors of loads, temperature changes, the basis of uneven settlement in the
deformation and the internal factor of concrete shrinkage. So it is necessary for us to study
the cause and affecting for crack in these structures.
In this thesis the cause of crack in a parking floor which is a ultra-long concrete
frame structure built in Beijing has been analyzed. And a reference is made to the crack
test report and safety evaluation report for this building, then FEM analysis method is used
to simulate the load on the structure and its response to discuss the cause of cracks
occurred by all loads for this kind of structure. In the FEM analysis seasonal temperature,
concrete shrinkage and vehicle load are applied to the FEM.
On the basis of the work mentioned above,some crucial conclusions are acquired as
follows. The FEM calculating result shows that the stress in seasonal temperature and
concrete shrinkage is the primary cause of cracks in this parking floor, while the stress in
vehicle loads cause the first floor of this parking floor cracking. It is doubltless that the
work done in this paper is beneficial to the application of linear analysis in