一、前言修建拱坝理想的地形是一个U型或V型的峡谷。由于提倡建筑拱坝,和比之其它坝型更具经济性,这种坝型己经在越来越宽的河谷修建。但是至今拱坝有时还会出现一些意想不到的问题——即预计的与实际观测到的情况不相符,比如在岩体中和坝体中观测到的裂缝情况,如图1所示。问题是,在设计中所用的计算方法是否 I. INTRODUCTION The ideal terrain to construct arch dam is a U-shaped or V-shaped canyon. With the advocacy of building arch dams, and more economical than other dams, the dams have been built in increasingly wide valleys. However, some unexpected problems have sometimes occurred in arch dams - that is, predicted and actual observations are not consistent with the observed fractures in rock masses and in dams, as shown in Figure 1. The question is, is the method of calculation used in the design?