环形阻尼结构设计及其阻尼层厚度的优化研究  

Research on Annular Damping Structure Design and Optimization of Damping Layer Thickness

作　　者：吕平[1] 陈凯华[1] 黄微波[1] 何鑫[1] 何筱姗 

机构地区：[1]青岛理工大学蓝色经济区工程建设与安全协同创新中心,山东青岛266033

出　　处：《防灾减灾工程学报》2016年第2期290-294,共5页Journal of Disaster Prevention and Mitigation Engineering

摘　　要：模拟地铁盾构隧道结构,设计了环形自由阻尼结构和环形约束阻尼结构。通过自由梁单点激振实验,探讨了阻尼层厚度对两种结构的复合损耗因子、振动加速度级等阻尼性能的影响规律,继而优化阻尼层厚度。环形自由阻尼结构实验结果显示：当阻尼层厚度在1~7 mm范围增加时,结构振动加速度幅值比无阻尼结构分别降低了1.1%~65.6%;同时,各阶复合损耗因子及增幅均逐渐增加,振动加速度级逐渐降低。环形约束阻尼结构实验结果显示：当结构无阻尼、阻尼层厚度为1、3mm时,后者的复合损耗因子相对前者分别增加了18.75%、8.91%,而当阻尼层厚度增至3mm以上时,结构复合损耗因子变化不大。研究结果显示：环形自由阻尼结构的阻尼性能随阻尼层厚度的增加而增强,环形约束阻尼结构在阻尼层厚度为3mm时具有较好的阻尼性能。Two kinds of damping structures,annular free damping structure and annular constrained damping structure,were designed to simulate the structure used in the damping system of subway shield tunnel.Through the free beam single-point excitation experiment,the effect law of the thickness of the damping layers on the damping performance,such as composite loss factor and vibration acceleration level,was discussed.Then,the optimal thicknesses of the damping layers of the two kinds of structures were found.The experiment results of annular free damping structure show that when the thickness of damping layer ranges from 1mm to 7mm,the vibration acceleration amplitude is reduced by 1.1%~65.6% respectively than the undamped structure.Meanwhile,the composite loss factor and its amplification increase,but the vibration acceleration level reduces gradually.The experiment results of annular constrained damping structure show that when the structure is undamped and the damping layer thickness of the damped structure are1 mm and 3mm,the composite loss factor of the latter are increased by 18.75%,8.91%respectively than the former.On the other hand,when the thickness increases to over 3mm,the composite loss factor changes little.Results of this research indicate that the damping performance of annular free damping structure increases with the increase of damping layer thickness.The annular constrained damping structure has better damping performance when its damping layer thickness is 3mm.

关 键 词：环形阻尼结构 自由梁激振实验 阻尼层厚度 复合损耗因子 振动加速度级 

分 类 号：O328[理学—一般力学与力学基础] TB535.1[理学—力学]