沟后水库溃坝原因初步分析

沟后水库总库容３３０万ｍ＾３，大坝为钢筋混凝土面板砂砾石坝，坝高７１ｍ。１９９３年８月２７日晚溃坝。初步分析溃坝原因是：渗流沿坝体上部施工层面逸出造成管涌破坏，并冲刷坝坡引起坝顶局部滑动，形成初期溃口，然后库水由口门大量下泄，进一步冲刷坝体，最终溃坝，设计时采用的控制砂砾石最大粒径的办法不可能起到控制砂砾石渗透性的作用。混凝土面砂砾石坝渗流控制的成功经验是在坝体中专门设置排水体。

Preliminary Analysis of the Causes of the Dam Break of the Gouhou Reservoir

Gouhou reservoir, with a total storage capacity of 3. 3 million m3. has a sandy gravel damwith reinforced concrete decks. The dam is 71m in height. The dam collapsed at the night of August 27, 1993. It is preliminarily analyzed that the causes of the dam break are f water seeped outof the upper construction layer resulting in suffusing damage. scouring dam slope causing partialsliding of the dam top and forming initial collapsing hole, then. water from the reservoir dis.charged through the hole, further scouring the dam body and eventually causing dam break. Controlling the maximum size of sandy gravel can not prevent the seepage throuth it. The successfulexperience of sandy gravel dam with reinforced concrete deks in Controlling seepage Lies in thearrangement of discharge system in the dam body.