地铁上盖隔震建筑车致振动实测与模拟分析

Measurement and simulation analysis of vehicle-induced vibration of isolated over-track building

为研究地铁振动引起的地铁上盖隔震建筑竖向振动的影响,基于上海徐泾车辆基地试车线旁的15层隔震住宅进行了现场测试与数值模拟,对不同车速工况下建筑物的室内振动进行测试与分析。振动测试结果表明:地铁上盖建筑采用普通橡胶支座隔震技术后,虽然振动经过隔震层后减小不明显,但并未发现上部结构Z振级有明显放大现象,较传统固接结构具有一定的优越性;上盖结构受车致振动的大小不仅与运行车速有关,也会受刹车等间接增大轨道不平顺程度的行为的影响。建立了用于地铁上盖隔震建筑振动分析的数值模型,并基于现场振动测试结果验证了模型的准确性。数值分析表明,隔震装置在一定程度上可减小楼板竖向振动的幅值,其1/3倍频程振级较固接结构在20、63 Hz附近低约6 dB。

In order to study the influence of the vertical vibration of the isolated over-track building caused by the operation of the subway,field tests and numerical simulations based on a 15-story isolated structure next to the test line of Shanghai Xujing vehicle depot were conducted under different speed of the subway.The test results showed that:by using the conventional rubber bearings,although the vibration is not significantly reduced after the vibration isolation layer is adopted,the Z-vibration level of the superstructure was not significantly amplified which shows certain advantages over the traditional fixed buildings.The impact of the vehicle-induced vibration on the over-track buildings is not only related to the operating speed of the subway,but also affected by the brake,which indirectly increase the track irregularity.The numerical model was established to analyze the vibration of isolated over-track buildings.Based on the results of field tests,the accuracy of the numerical model was verified.The numerical analysis shows that the vibration isolation device can reduce the vertical vibration amplitude of the floor,and its 1/3 frequency vibration level is about 6 dB lower than that of the fixed structure corresponding to the frequency of 20 Hz and 63 Hz.