高层建筑风振时地基土材料阻尼比取值范围的初探  

Preliminary Study of Material Damping Ratio Range for Foundation Soil of High Rise Building under Wind Induced Vibration

作　　者：李安勇[1,2] 陈镕[1] 薛松涛[1,3] 唐和生[1] 吕鹏[1] 

机构地区：[1]同济大学结构工程与防灾研究所,上海200092 [2]苏州科技学院土木系,苏州215011 [3]日本近畿大学理工学部,日本大阪577-8502

出　　处：《力学季刊》2008年第3期455-461,共7页Chinese Quarterly of Mechanics

摘　　要：高层建筑风振响应分析中考虑土与结构相互作用后地基土的材料阻尼比幅值是多少,这是考虑土与结构相互作用对高层建筑结构风振响应有利还是不利的关键问题。通过对无桩基桩架-剪力墙结构的顺风向风振响应分析,发现考虑土-结构相互作用时结构基础底面土体的动剪应变幅值处于弹性应变范围,根据土动力学中土的动剪应变与土的阻尼比的关系,土体的材料阻尼比较小,其值不超过0.03,据此计算出相应的结构最大层间位移和结构顶层的最大加速度比将地基视为刚性的结构有较大增长;因此,在高层结构风振响应分析中应考虑土-结构相互作用的影响。文章通过实例分析给出无桩基高层建筑土体材料阻尼比的建议值,该研究为有桩基高层建筑的土体材料阻尼比的计算提供了借鉴。After considering soil-structure interaction（SSI） effects to the along-wind vibration response of high-rise building, the range of material damping ratio of foundation Soils is the key factor whether the effect of SSI is favorable or not for the response of the structure under wind induced vibration. After ana- lyzing the response of frame-shear wall structures without piles under the along-wind induced vibration considering soil-structure interaction, it is found that the dynamic shear strain of the soil is in elastic range. According to the relationship between the damping ratio and shear strain the material damping ratio of foundation Soils is less than 0.03, and the corresponding maximum story displacement and the acceleration response is greater than that when the soil foundation is considered as rigid. For the safety of high-rise structures, the effect of SSI should be considered to analyze the response of frame-shear wall structures without piles under wind induced vibration. The suggested value of material damping ratio for the soil of this kind structure was given. The analytic approach provides useful reference for more higher structures with piles.

关 键 词：土-结构相互作用 高层建筑 风振响应 土动力学 动剪应变 材料阻尼比 

分 类 号：TU311.3[建筑科学—结构工程] TU43