【摘要】 研究了混凝土的收缩徐变对框架结构受力的影响。首先根据线性徐变的迭加原理,推导了混凝土构件截面在多级荷载作用下的徐变估算公式,该式可以考虑加载龄期、加载速度、构件厚度以及环境相对湿度对徐变的影响;然后给出了考虑施工过程和收缩徐变影响的框架结构竖向位移和位移差的计算方法。用该方法对一高层框架进行收缩徐变分析,结果表明:该方法简单实用,可以在超高层建筑结构设计中估算收缩徐变时使用,收缩徐变对框架结构的受力影响较大,在工程设计和施工中不能忽略其影响。更多还原

【Abstract】 Shrinkage and creep effects of concrete in frame structures were researched.Based on the superposition principle of linear creep,firstly,the calculation formulas of creep strain of member’s cross-sections under multi-loading were deduced.The effects of loading-age,loading-rate,member thickness and surroundings relative humidity on the creep could be taken into account in these formulas.Then,the method to determine vertical displacement and displacement difference in frame structures was presented.The shrinkage and creep effects of a tall frame structure were analyzed by using this method.The results show that this method is simple and applicable in estimating shrinkage and creep for design of high-rise building structures.It is also shown that shrinkage and creep of concrete have great effects on the mechanical performances of frame structures,and can not be neglected in engineering design and construction.更多还原