PLYWOOD PANEL REINFORCING JOIST, PLYWOOD PANEL REINFOCING STRUCTURE AND CLOSING METHOD AFTER DISMANTLING OF THE PLYWOOD PANEL REINFOCING STRUCTURE

摘要

A band steel type joist for reinforcing plywood molds and reinforcing structure of the plywood molds using the joist, and a method of finishing the concrete after disassembling the reinforcing structure are provided to counter the lateral pressure exerting on the plywood molds by cutting sharp pointed coupling chips from body units of the joist which are thrust to the back side of the molds, and by integrating form ties with the molds by screwing cone nuts through the molds and joist, and by filling the concrete holes left by the cone nuts with padded caps respectively. A bad steel type joist for countering the lateral pressure of the concrete exerting on the plywood molds includes body units(110) and plural coupling units(120). The body units are longitudinal metal members having two parallel lines of support sills(111) disposed along the length of the body units. Each of the coupling units have three pieces of coupling chips(121) cut out in sharp points from plate surfaces of the body units and bended so as to point in opposite direction of the supporting sills. Each of the coupling chips are pointed in different directions. In a reinforcing structure for countering lateral pressure of the concrete exerting on plywood molds, plural plywood molds are linked together. Band steel type joists(100) are fixed across the back surface of the plywood molds by thrusting coupling chips into the plywood molds. Plural form ties are penetrated through between two lines of supporting sills and integrated to the plywood molds. The form ties include steel tie bolts having male threaded portions on two ends, cone nuts having one ends allowing insertion of the male threaded portion of the tie bolts and other ends contacting the plywood molds, and cone nut fixers penetrating through the joists and plywood molds to be inserted into the cone nuts and screwed to the tie bolts. A method of finishing the concrete after dismantling the plywood molds include pouring and curing into the plywood molds reinforced with the joist and form ties, dismantling the molds, and filling concrete holes left by cone nuts with pad caps having air ventilation holes.