短语词组短語cement purdah 帷幕截流grouting purdah 灌漿帷幕underground purdah 井下帷幕purdah grouting 基礎帷幕灌漿purdah stake 帷幕樁watertight purdah 止水帷幕purdah panel wall 帷幕板牆 返回 purdah