The reason for this phenomenon was imperfect construction control,large settlement of the rockfill dam and deflection of facing element due to the reservoir impoundment.

• 下期面板施工前,在对上期面板进行检查时发现,面板与大坡面产生脱空,其主要原因是施工组织欠妥、大坝沉降量大及水库蓄水使面板产生挠曲变形所致。