软土地铁车站中柱在强震作用下的响应研究

将汶川地震时获得的地震波作为输入波，利用FLAC^3D软件对软土典型地铁车站中柱进行强震响应的三维数值模拟。土体采用D—P本构模型，车站结构采用弹性模型，并选用瑞利阻尼和Hardin／Drnevich模型的滞后阻尼来实现土在循环动荷载下的滞回和非线性。计算结果包括中柱的相对变形、轴力、剪力、弯矩及车站中柱的加速度响应规律。结果表明：下层中柱是地铁车站受地震波作用时最为薄弱的构件，并且中柱的破坏系水平向地震波和竖直向地震波共同作用的结果。

Study on Response of Centre Column of Metro Station in Soft Soils to Strong Earthquake

With the seismic wave recorded in Wenchuan earthquake as the input, the centre column of a typical metro station was simulated numerically by the software FLAC^3D for its strong seismic responses. The D-P constitutive model was assumed for the soils, the elasticity for the station structure, and Rayleigh damping and Hardin/Drnevich model of hysteretic damping were used to simulate the nonlinearity and hysteresis of the soils under cyclic dynamic loading. The computational results include the relative deformation, axial force, shearing force, bending moment in the centre column, as well as its regularity of the acceleration response. They show that the centre column on the lower floor is the weakest component of the station structure in earthquake, and its damages are due to the combined effects of horizontal and vertical ground motions.