一、从一座试验性拱坝的破坏谈起几年前,在我国沿海一条小溪出口处,建造过一座试验性的砌石薄拱坝、最大坝高22m,坝顶厚1.0m,底厚1.2m,为定圆心等半径圆筒型式。坝顶长64.35m,外半径40m中心角从顶到底变化在92°10′～32°40′之间。在坝顶中部设有长22m的溢流堰,堰顶低于坝顶0.7m,详见图1(a)。为了试验,在坝身近基岩处设有一道周边缝,缝在河床部位呈水平平面,位于坝顶下15.7m,见图1(b)。两岸斜坡部位呈弧形面,其上端终止于坝顶以下1.7m处,见图 First, from the destruction of a experimental arch dam A few years ago, in our coastal exit of a creek, built a pilot stone masonry dam, the maximum dam height 22m, the top of the dam thickness 1.0m, the bottom thickness 1.2m, such as the radius of the center of the cylinder type. The crest of the dam is 64.35m long, and the center angle of the 40m outer radius varies from top to bottom between 92 ° 10 ’and 32 ° 40’. In the middle of the crest, a weir with a length of 22m is provided. The weir crest is 0.7m below the top of the crest, as shown in Figure 1 (a). In order to test, there is a perimeter seam near the bedrock of the dam body. The seams are horizontal in the river bed and lie 15.7m below the crest of the dam, as shown in Figure 1 (b). The slopes of both sides of the Strait are arc-shaped, with the upper end terminating at 1.7m below the crest, see photo