回字形超长框架结构温度应力设计

在理论分析和现场长期测试的基础上,针对回字形超长框架结构的特点,研究了该类结构的温度应力设计方法.采用余弦函数模拟季节温度变化,应用CEB-FIP MC90规范中的收缩公式及JTJ023—85规范中的徐变本构关系和徐变计算的继效流动理论,结合考虑徐变应力折减系数的简化计算方法,对实际工程进行了温度应力分析,分析结果与现场测试结果吻合.分析表明,回字形框架的楼面角点、角柱、边梁、楼面中间区域为温度应力设计的关键部位,在这些关键部位配置适量通长普通钢筋即可控制温度及收缩裂缝,且对结构造价影响很小.

Temperature stress design of overlong rectangular-ambulatory-plane frame structure

Based on the theory analysis and long-term test, as well as the characters of overlong rectangular-ambulatory-plane frame structure, the design method of the temperature stress in this kind of structure is discussed. Combined with seasonal temperature changes simulated by cosine function, shrinkage equation in CEB-FIP MC90, creep equation in code JTJ023 -- 85 and aftereffect flow theory, and the method of creep stress reduction coefficient, temperature stress in the project is studied and the results gained are consistent with test results in site. Analysis indicates that the key positions of rectangular-ambulatory-plane frame in design of temperature stress are comer of floor, comer col- umns, side beams, and central field of floor. It is found that layout of proper amount of continuous bars in these key positions can control crack width caused by temperature and shrinkage, and the additional engineering cost is very low.