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液壓伸(shen)(shen)縮式活(huo)(huo)動(dong)模(mo)(mo)(mo)板(ban)(ban)是在井(jing)(jing)筒混合作業(ye)時(shi)，隨工(gong)作面(mian)前進自上而(er)下現澆(jiao)混凝土(tu)時(shi)使用(yong)的(de)一種(zhong)(zhong)(zhong)整(zheng)體(ti)移動(dong)模(mo)(mo)(mo)板(ban)(ban)，它是我國(guo)各種(zhong)(zhong)(zhong)活(huo)(huo)動(dong)模(mo)(mo)(mo)板(ban)(ban)中使用(yong)的(de)最多的(de)一種(zhong)(zhong)(zhong)，這種(zhong)(zhong)(zhong)模(mo)(mo)(mo)板(ban)(ban)的(de)基(ji)本構(gou)造是：在井(jing)(jing)筒全部(bu)圓周上，模(mo)(mo)(mo)板(ban)(ban)分(fen)為2~3大塊(kuai)，大塊(kuai)之間(jian)留有伸(shen)(shen)縮縫，依靠某種(zhong)(zhong)(zhong)機構(gou)使伸(shen)(shen)縮縫伸(shen)(shen)縮以達到模(mo)(mo)(mo)板(ban)(ban)的(de)撐(cheng)開和收攏。