木楼板和混凝土楼板振动舒适度的对比分析

摘要

为探讨木楼板和混凝土楼板的振动舒适度,对其进行了对比分析.通过有限元软件对楼板进行模态分析,得到其自振频率,并与理论值进行比较,两者极为接近.在此基础上,分析了木楼板和混凝土楼板在行走荷载作用下的振动响应.研究结果表明:同等条件下,木楼板的自振频率比混凝土楼板更大,从自振频率这一指标来看,木楼板的振动舒适度更好;但是木楼板在行走荷载作用下的峰值位移、速度以及加速度比混凝土楼板大得多,从振动响应这一指标来看,木楼板的振动舒适度则比混凝土楼板要差得多.在有限元分析的基础上,建议采用限制频率和限制楼板的振动响应的双重指标作为木楼板振动舒适度的评价标准,并可采用限制楼板的尺寸、优化结构体系以及使用组合楼板等方法来提高木楼板的振动舒适度.%Comparative analysis was carried out to discuss the vibration comfort of timber slab and concrete slab.Finite element modeling (FEM) was conducted to achieve the natural frequencies of slabs.The results obtained from FEM showed good agreement with theoretical results.Based on the modeling,vibration responses of slabs under human walking loads are analyzed.The research showed that natural frequency of timber slab was greater than that of concrete slab,and from the point of frequency-based index,the vibration comfort of timber slab is better.However,the peak values of displacement,velocity and acceleration of timber floor under human walking loads are much bigger than those of concrete slab respectively,and from the point of vibration response-based index,the vibration comfort of timber slab is much worse than concrete slab.Based on finite element simulation,it is recommended to apply both frequency-based index and vibration response-based index to evaluate the vibration comfort of timber slab.Meanwhile,some measures (size restrictions,structural optimization and development of composite slab) are presented to improve the vibration comfort of timber slab.