体育馆大跨度预应力次梁楼盖竖向振动模态分析

以重庆市铜梁县新城核心区小学建设项目3#楼(体育馆)工程为背景,对其大跨度预应力次梁楼盖竖向振动模态进行模拟分析,并与实测结果相比较,评价其控制竖向振动舒适度的效果。根据建模思路精确建立的该大跨楼盖有限元模型,其模态分析结果与模态实测结果接近,相对误差约为5%;模拟分析及工程实测结果表明,该大跨楼盖前三阶振型均以竖向振动为主,结构自振基频满足我国现行相关规范的要求,竖向振动舒适度符合标准;与无底板的大跨次梁楼盖相比,增加底板后,其增幅最小的一阶频率增长了19.9%,表明增加底板可有效地控制大跨度预应力次梁楼盖的竖向振动。

Vertical vibration modal analysis of long-span prestressed secondary beams floor system in gymnasium

The construction project 3^# (gymnasium) building of Core Area Primary School in Tongliang county in Chongqing was taken as the research subject. The vertical vibration modal of long-span prestressed secondary beams floor system was analyzed on simulation. Then the analysis results were compared with the measured results to evaluate the control effect of vertical vibration comfort, and the main conclusions include:the results of the modal analysis of the established accurate finite element model of the long-span floor on the basis of the modeling method are close to the measured results, and the relative error is about 5%. The simulation analysis and engineering measurement show that the first three order vibration modes of long-span floor are dominated by vertical vibration. The fundamental frequency of the structure meets the requirements of the current relevant codes in China, and the vertical vibration comfort conforms to the standard. Compared with the long-span floor which has no bottom plate, the first-order frequency has the smallest increase and it increases by 19.9% after adding bottom plate, which shows that the increase of bottom plate can effectively control the vertical vibration of long-span prestressed secondary beams floor system.