Abstract: An expansion joint for use in constructing concrete material structures of the present invention has a plurality of sandwich type composite plates each comprising a sheet-like elastic body sandwiched by a pair of hard plates with a rib at both surfaces thereof are connected with each other through a water-swelling rubber.

Abstract: The present invention relates to a device for filling up a recess left in a concrete wall after removal of a separator terminal, the device comprising a main body including a circumferential step formed around its outer periphery at a longitudinal intermediate location so that the circumferential step defines a diameter-reduced portion and a diameter-enlarged portion of the main body, a threaded hole centrally formed and axially extending in an end surface of the diameter-reduced portion to be engaged with a threaded end of the separator, tool receiving apertures formed in an end surface of the diameter-enlarged portion and in elastic water-swollen rubber cylinder put around the diameter-reduced portion so that an outer periphery of said cylinder is tapered towards the end surface of the diameter-reduced portion and an end surface of the cylinder looking towards the end surface of the diameter-enlarged portion bears against the step of the main body while the end surface of the cylinder looking towards the en

Abstract: The present invention relates to a device for prevention of rainwater or like from penetrating into a concrete structure around each separator left embedded therein, the device comprising a hollow cylinder of synthetic resin, the latter including a female threaded cylinder made of metal or other material embedded in the interior at one end thereof and water-swollen damming-up outer rings fixed on the outer periphery so as to serve together as terminals, a threaded cylindrical portion formed at one end of each of the terminals being engaged with a male threaded portion formed around the corresponding end of the separator, and the cylinder of synthetic resin further including a plug provided with a water-swollen damming-up inner ring fixed into the interior at the other end thereof.

Abstract: Water-swellable moisture-curing one-package polyurethane sealant which includes (1) a water-swellable polyurethane prepolymer having 1.5-10% terminal NCO group content obtained by reacting polyisocyanate with polyoxyalkylenepolyol having 50-90% of oxyethylene units based on polyalkylene chain molecular weight (2) non water-swellable polyurethane prepolymer having terminal NCO groups obtained by reacting polyisocyanate with polyoxyalkylenepolyol having 3-4 carbon atom oxyalkylene units, and (3) a filler. The sealant exhibits has been improved storage stability.