本文建立了在三维地震力作用下平板型空间网架的振动方程,采用子空间迭代法求网架自振频率和振型。并列出了电算程序的框图。利用此程序分析了十四个不同型式、不同跨度的网架的地震反应,用回归分析方法得出竖向荷载系数C_Z值的计算公式。 In this paper, the vibrational equations of the flat space grid under the action of three-dimensional seismic force are established. The subspace iteration method is used to find the free vibration frequency and mode shape of the grid. And listed the block diagram of the computer program. Using this program, the seismic responses of fourteen different grids with different spans were analyzed. The regression formula was used to calculate the value of the vertical load coefficient C_Z.