基于随机等价线性化法的悬浮隧道锚索随机振动研究

为了得到悬浮隧道锚索在随机环境激励作用下的响应,建立了悬浮隧道锚索非线性随机振动方程,并在方程中考虑了锚索的垂度效应,随后采用随机等价线性化法对随机激励作用下锚索的振动响应进行了分析。研究结果表明:在零均值高斯白噪声环境激励作用下,锚索的跨中位移和速度均方根响应经过一定时间后将趋于定值,位移和速度的互相关函数趋于零;锚索的阻尼比越大,锚索跨中横向位移均方根响应越小;激励的功率谱密度强度越大,锚索跨中横向位移均方根响应越大;由于水体阻尼力的存在,悬浮隧道锚索的位移和速度均方根响应比空气中锚索的响应大幅减小。

Random vibration analysis of a submerged floating tunnel's tether based on stochastic equivalent linearization method

To study the response of submerged floating tunnel tether subjected to random ambient excitation, a non-linear random vibration equation of tether is established considering tether sag. Subsequently, the vibration response of tether is analyzed by means of stochastic equivalent linearization method. The results indicate that, the mid-span displacement and velocity root mean square response of tether subjected to zero-mean Gaussian white noise excitation tends to stable value after a certain period of time, while the cross-correlation function of mid-span displacement and velocity tends to zero; the mid-span displacement root mean square response of tether decreases as its damping ratio increases，whereas it increases as power spectral density of excitation increases; due to the existence of water damping force, the displacement and velocity root mean square response of tether decreases rapidly compared with tether in air.