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液壓伸(shen)(shen)縮式活動模板(ban)(ban)(ban)(ban)是在井筒(tong)混合作(zuo)業時，隨工作(zuo)面前進自上(shang)而(er)下(xia)現澆混凝(ning)土時使(shi)(shi)用的(de)一(yi)種(zhong)整(zheng)體移動模板(ban)(ban)(ban)(ban)，它是我國各種(zhong)活動模板(ban)(ban)(ban)(ban)中使(shi)(shi)用的(de)最多的(de)一(yi)種(zhong)，這種(zhong)模板(ban)(ban)(ban)(ban)的(de)基本構造(zao)是：在井筒(tong)全部圓周上(shang)，模板(ban)(ban)(ban)(ban)分為2~3大塊，大塊之間留有伸(shen)(shen)縮縫，依靠某種(zhong)機構使(shi)(shi)伸(shen)(shen)縮縫伸(shen)(shen)縮以達到模板(ban)(ban)(ban)(ban)的(de)撐開(kai)和收攏(long)。