外墙外保温系统的地震作用分析

【作者】 任瑜；

【导师】 丁建国； 葛雪康；

【作者基本信息】 南京理工大学 ， 建筑与土木工程， 2010， 硕士

【摘要】 我国人均能源资源拥有量小于全世界人均水平的一半,为了实现经济可持续发展战略,在建筑节能方面,中国政府给予了足够的重视,特别是近期颁布的《节能中长期专项规划》明确规定：“十一五”期间,新建筑要严格执行节能标准,现有建筑要逐步实施节能改造。目前,我国应用较多的建筑保温技术为安装在结构墙体之外的外墙外保温系统,但对这种非结构构件在地震作用下的安全性能研究还较少,因此进行外墙外保温系统的地震作用分析具有重要的现实意义。本文通过理论分析和ANSYS有限元计算分别研究了外墙外保温结构在多遇地震作用下的弹性反应及在罕遇地震作用下的弹塑性反应,并得到如下主要成果。(1)通过建立外墙外保温结构力学模型,推导出外墙外保温结构在地震作用下的运动方程,并采用Matlab语言编制了地震作用下时程分析的计算程序。(2)通过分析保温系统对结构周期的影响发现,保温系统将使建筑结构各阶振型所对应的结构周期变大,因此在进行结构设计时,要特别注意保温系统对建筑结构周期的影响。(3)通过对外墙外保温系统进行多遇地震作用下时程分析得到,主体结构中间层在多遇地震作用下所产生的地震作用较大；各层保温系统处加速度最大值要明显大于各层主体结构处加速度最大值；主体结构和保温系统位移最大值均发生在中间层；高层处保温系统与主体结构之间相对位移较大。(4)当主体结构刚度由小变大时,各层主体结构和保温系统最大位移均逐渐减小；随着主体结构刚度的增大,保温系统加速度逐渐减小；保温系统质量的变化几乎对各层主体结构及保温系统最大位移不产生影响；保温系统质量的改变对主体结构各楼层最大加速度没有影响；随着保温系统质量的增加,对保温系统各层最大加速度有增大的趋势。(5)通过ANSYS有限元分析得到,在罕遇地震作用下,主体结构最大弹塑性位移出现在高层处,而保温系统最大弹塑性位移则发生在中间层处；在较高层时主体结构与对应的保温系统之间发生弹塑性变形所产生的最大相对位移值很大。更多还原

【Abstract】 The percapita availability of energy in China is lower than half of the average level in the world. To realize sustainable development of economic society, Chinese government has paid enough attention to the aspect of building enery conservation, especially for the’Energy saving medium-long term special planning’. It has been clearly stipulated that the energy saving standard and transformation should be strictly carried out in the new and existing bulidings, respectively. At present, exterior wall external insulation system is widely used in our country. But, there is less study on safety of exterior wall external insulation system under earthquake action. Thus, it is of great practical significant on asismic analysis of exterior wall external insulation system. Based on theoretical and FEM methods, the present paper investigates the elastic and elastic-plasic response of exterior wall external insulation structure under frequently and rare occurred earthquake. The following conclusions can be drawn:(1) Based on the proposed mechanic model of exterior wall external insulation system, the corresponding motion equation is deduced under earthquake action, and a time history program is also developed by Matlab software.(2) The insulation system can increase the vibration periods of structure modes and should be taken into serious consideration.(3) A time history analysis of exterior wall external insulation system under frequently occurred earthquake is carried out. The results show that the maximum earthquake action occurs at the mid-floor of the main structure; the maximum acceleration of insulation system at every floor is much bigger than that of the main structure; the maximum displacements of both main structure and insulation system are occur at the mid floor, and the maximum relative displacement between main structure and insulation system is on the top floor.(4) The maximum displacement and acceleration of insulation system at every floor decreases gradually with increasing the structure stiffness. There is no significant influence of the mass of insultion system on the maximum displacement of main structure and insulation system at every floor. The maximum acceleration of insulation system will increase due to the greater mass of insulation system, but mass of insulation system has no effect on the maximum acceleration of main structure.(5) A FEM analysis on the overall structure under the action of rare occurrence earthquake is finished. The results show that the top floor has the maximum elastic-plastic displacement of the main structure; however, the maximum elastic-plastic displacement of the insulation system occurs at the mid floor. In addition, the maximum relative displacement takes place at the upper floor.更多还原