摘要
对冷弯薄壁型钢梁-OSB板组合楼盖足尺模型进行改变边界条件的振动试验,研究组合楼盖在四边支撑和梁端简支、四边支撑和梁端固结、两边支撑和梁端简支、两边支撑和梁端固结四种不同边界条件时静力荷载下的挠度及人沿平行和垂直楼盖梁方向行走、脚跟冲击、沙袋从空中落下、激励锤冲击不同动力荷载工况下的自振频率。研究表明:边界条件的变化会引起组合楼盖挠度和自振频率的变化,可以通过改变边界条件来提高组合楼盖的振动性能;边界条件不同时组合楼盖在1kN集中荷载作用下跨中挠度均小于2mm,在动力荷载作用下除个别情况外自振频率均高于15Hz,建议组合楼盖在1kN集中荷载作用下跨中挠度限值设为2mm,振动舒适度要求较高时自振频率限值设为15Hz。另外,采用等效刚度法提出的理论公式能较好地预测不同边界条件时组合楼盖在静力荷载下的挠度及动力荷载下的自振频率。
A full scale cold-formed steel OSB composite floor with different boundary conditions was tested to study its vibration behavior. The center deflection of the composite floor under static loading and the fundamental frequency were tested under dynamic loading which includes walking along and transverse to a beam, heel shock, sandbags dropped from the air and hammer impact. Each load case considered four boundary conditions including four sides support and beam end simply supported, four sides support and beam end fixed, two sides support and beam end simply supported, two sides support and beam end fixed. The research showed that changes in boundary conditions would cause changes in the deflection and the fundamental frequency of the composite floor. The vibration performance of the composite floor can be improved through changing the boundary conditions. The maximum deflections were all less than 2mm under 1kN concentrated load and the fundamental frequency was generally greater than 15Hz under dynamic loadings in different boundary conditions. Thus, it is proposed the maximum deflection limit of the cold-formed steel OSB composite floor can be set to 2mm and the fundamental frequency limit can be set to 15Hz when the higher comfort requirement is demanded. The theoretical formulas proposed in this paper which adopted the equivalent stiffness method can be used to predict the deflection under static loads and the fundamental frequency under dynamic loads for the composite floor with different boundary conditions.
出处
《工程力学》
EI
CSCD
北大核心
2014年第5期211-217,共7页
Engineering Mechanics
基金
国家自然科学基金项目(51108033)
中央高校基本科研业务费专项资金项目(CHD2012ZD006)
关键词
组合楼盖
冷弯薄壁型钢
振动性能
试验研究
理论公式
composite floor
cold-formed steel
vibration performance
experimental study
theoretical formula
