轨道交通荷载下高层框架结构的动力响应

Dynamic Response of High-level Framework Under Rail Loads

为了减小轨道交通引起的环境振动对线路沿线建筑结构的影响,通过研究建筑结构在轨道交通引起的地面振动激励作用下的振动响应,以便采取相应措施降低轨道交通运行对结构的不利影响。利用ANSYS/LS-DYNA显式分析程序对轨道交通引起的地面三向、竖向和水平振动激励作用下20层框架结构的振动响应进行了分析,得到了不同振动激励作用下结构各层的振动响应,以及各层峰值速度随着结构高程的变化规律。研究指出在轨道交通振动荷载作用下,结构3个方向的振动速度峰值的最大值都出现在第1层,结构也没有出现常规所认为的那样存在随高程的放大效应,即"层数越高,质点的振动速度峰值越大"的现象,甚至在某些方向上呈现了相反的变化趋势。

In order to reduce the vibration influence caused by rail traffic to the structures along the lines,and take appropriate measures to reduce the adverse effects on the structure by studying laws of the ground vibrations caused by rail traffic.In this paper,we studied the vibration response of a twenty-floor frame structure under the three-floor,vertical and horizontal vibration excitation caused by rail traffic through ANSYS / LS-DYNA explicit analysis programs,and we know the vibration response of different structures under different vibration excitations,and the change of peak velocity with the elevation changing of the structure,pointing out that,under rail loads,the maximum of peak vibration velocities of the structure in the three directions appeared in the first layer,and the structure does not show the amplification effect with the height,that ＂the higher layers,the greater vibration peak velocity＂,even in some direction showing the opposite trend.