短语词组短语cement purdah 帷幕截流grouting purdah 灌浆帷幕underground purdah 井下帷幕purdah grouting 基础帷幕灌浆purdah stake 帷幕桩watertight purdah 止水帷幕purdah panel wall 帷幕板墙 返回 purdah