提堂坝(图1)的失事发生在1976年6月5日早晨,当时水库正处在第一次蓄水期间。水库是自1975年10月3日开始蓄水的,失事时,原河床以上的水深约84 m,低于最高正常库水位7 m。因此,平均蓄水率约为34 cm/天。在失事发生前10 h,没有明显的失事征兆。6月5日上午7:00时左右,在坝的右岸接头处第一次看到初始的事故性 The tomb of Tiantangba (Figure 1) occurred on the morning of June 5, 1976, when the reservoir was in its first impoundment. The reservoir started to accumulate water on October 3, 1975. At the time of the accident, the water depth above the original riverbed was about 84 m, which was below the water level of the highest normal reservoir by 7 m. Therefore, the average water storage rate is about 34 cm / day. In the 10 hours before the crash, there was no obvious sign of calamity. At about 7:00 a.m. on June 5, for the first time at the dam’s right bank junction, initial accidental