本文旨在以理論解析的方式，探討水平雙鉸曲梁於水平地震下受串列移動質量之「面內」動力反應。由於地震對支承作用，導致吾人須面對求解具有時變性非齊性邊界條件之動力問題，針對此課題，本文將藉由擬靜態方法，透過解析的方式探討本課題。從解析計算過程，吾人將可得到水平曲梁受串列移動質量與地震作用下之動態反應。從說明例顯示， 地震之引進將會明顯地放大曲梁之反應，而曲梁之最大反應也並不一定會發生在跨度中央位置。 In this paper, in-plane vibration for a horizontally two-hinged curved beam due to horizontal ground excitations and the centrifugal force generated by successive moving masses will be presented. By using the quasi-static decomposition method to solve such a dynamic problem with time-dependent boundary conditions, the dynamic deflection response of the curved beam can be separated into two parts: quasi-static and dynamic components. Then, the closed form solution of quasi-static deflection for the curved beam shaken by horizontal support excitations is first derived using an analytical approach. Then, one can adopt Galerkin's method to solve the dynamic part of the total deflection of the curved beam. With the utilization of Newmark's j3 method to compute the dynamic response of the curved beams subjected to successive moving masses and horizontal ground excitations, the numerical results indicate the earthquake excitations may amplify the response of the curved beam due to moving masses, and that the maximum deflections on the curved beam may need not to occur at the mid-span.