土坝的沉陷过程一般规律是:初期沉陷量大,曲线较陡;以后沉陷逐渐减小,曲线较为平缓。在某些书中采用双曲线建立其沉陷与时间两者间的回归方程,这种论述不够确切。因为双曲线表现形式如图(一)所示,开始,曲线是垂直下降,继之又急速的平缓下来,它近似 The general rule of earth dam subsidence is that the initial settlement is large and the curve is steep; afterwards, the subsidence gradually decreases and the curve is gentle. The use of hyperbola in some books to establish the regression equation between its subsidence and time is not sufficiently precise. Because hyperbolic forms as shown in Figure (a), the curve begins to decline vertically and then slows down rapidly. It approximates