基于舒适度的大跨度楼盖结构人致振动分析与试验研究

The long-span floor structure, characterized with low natural frequency, which closes to the dominant frequency of the crowd, as well as small damping, is prone to suffering remarkable vibration under crowd loadings and its serviceability, therefore, becomes a tough problem..The key issues of crowd-induced vibration problem of long-span floor structures are the accurate computation of the dynamic characteristic of the structure and the proper simulation of the crowd..As the structure keeps in elastic state under crowd loading, the contributions of non-structural components (e.g. decorative surface) to the dynamic characteristic of the structure cannot be neglected. However, the simplified simulation method has not been systematically reported. Moreover, people either be stationary or in motion would affect the dynamic characteristics of the structure. However, these two types of crowds are rarely considered simultaneously in crowd-induced structural analysis..In this study, a combination of theoretical analysis, numerical simulation, model test and field measurement methods will be employed to conduct the research: the simplified simulation method of nonstructural components will be developed by theoretical analysis and the results will be validated and improved by model test and field measurement methods so as to propose a refined structural analytic model. Then a random crowd - floor coupled model will be presented by considering both stationary and mobile crowd. The model will be verified and improved by results from model tests and field measurements. Finally, the dynamic analysis method of long-span floor structures under crowd loadings will be presented. The results obtained would provide references to improvement of the analysis of long-span floor structures.

大跨度楼盖结构由于自振频率低且与人行荷载的主频段较为接近、阻尼小，人群作用下结构振动响应较为显著，其舒适度问题十分突出。.大跨楼盖结构人致振动问题的核心在于结构动力特性的准确把握和人群荷载的合理模拟。人群作用下结构处于线弹性状态，非结构构件（如装饰面层等）对结构动力特性的影响不可忽略，而其简化模拟方法尚不完善。此外，静止人群和活动人群均会改变结构的动力特性，而目前的人致振动分析却较少同时考虑二者的影响。.拟采取理论分析、数值模拟、模型试验与现场测试相结合的方法开展研究：通过理论分析建立非结构构件的简化模拟方法，基于模型试验和测试结果对其进行修正和完善，进而建立结构的精细化模型；同时考虑静止人群和活动人群与结构的耦合作用，建立随机人群-楼盖竖向相互作用模型，并通过人-结构相互作用试验对其进行验证和完善，最终建立大跨楼盖结构的人致振动分析方法。研究成果可为完善大跨楼盖的振动分析提供参考。

大跨度楼盖结构的轻质、低频、小阻尼特性使得其在人行动荷载下的动力性能成为基于舒适度的结构设计和减振控制领域的研究热点和前沿。人员活动时不仅会产生动荷载，也会与结构相互作用，特别是当人/结构质量比较大时，这种相互作用会显著的改变结构动力特性。作为结构动力分析的基础，对结构动力特性的深入研究和准确把握无疑对结构设计和结构振动控制大有裨益，特别是当结构设计主要由振动舒适度指标控制时。本项目重点研究基于舒适度的结构模型构建方法和考虑人-结构相互作用的人致振动分析方法。通过理论分析建立非结构构件的简化模拟方法，基于模型试验和测试结果对其进行修正和完善，建立了结构的精细化模型；同时考虑静止人群和活动人群与结构的耦合作用，建立随机人群-楼盖竖向相互作用模型，并通过人-结构相互作用试验对其进行验证和完善，最终建立大跨楼盖结构的人致振动分析方法。