适用于优化建筑结构声振特性的多重模态减缩策略

Hybrid mode synthesis strategy for optimizing vibro-acoustic characteristics of building structures

建筑结构的声振特性是衡量建筑舒适性的重要指标之一,也是直接影响建筑使用寿命的重要因素,开展建筑结构声振特性优化的设计方法研究具有重要的工程意义。以建筑结构为研究对象,将其看作声固耦合系统——固体域为混凝土材质的楼板和墙壁板构成的长方体结构,结构内部腔体填满可压缩空气。引入分支模态发展了多重模态综合理论,建立了基于子结构固定界面模态、连接面分支模态和声学体自由子结构模态的减缩模型,极大地提升了声固耦合系统声振特性的分析效率;基于该减缩模型发展了一套建筑结构内部声压级优化方法,重点分析了建筑结构内部声压级与墙壁厚度、楼板-墙壁连接面上刚度之间的定量关系,并以腔体内部平均声压级为优化指标给出了优化策略。本文所提出方法和分析结果可为建筑结构声振特性的分析和设计提供参考。

The vibro-acoustic characteristics are very most important in evaluating the living comfort and the service life of build⁃ings.Therefore,it is of great significance to optimize the vibro-acoustic characteristics of buildings.This research has considered the building system as a coupled fluid-structural system:the structural part is a rectangular structure made of concrete material,and the fluid part is the cavity inside the rectangular structure filled with compressible air.In this work,a hybrid mode synthesis strate⁃gy has been developed to analyze the vibro-acoustic characteristics of buildings:on the one hand,the branch mode is introduced to develop the hybrid mode synthesis theory,and the corresponding reduced model has been built based on the fixed interface mode,branch mode and free interface mode,which greatly improves the analysis efficiency of the acoustic-structural system.On the other hand,based on the reduced model,an optimization strategy by minimizing the Sound Pressure Level(SPL)in the cavity is devel⁃oped,and typical focus include the quantitative relations between the SPL and the thickness of the wall along with floor-wall con⁃nection stiffness.This work aims at providing an efficient method for optimizing vibro-acoustic characteristics of buildings.