Abstract: Provided is a pregrouted PC steel material comprising a PC steel stranded wire composed of a plurality of steel wires, a pregrout layer disposed on the outer periphery of the PC steel stranded wire so as to accommodate the PC steel stranded wire, a sheath covering the outer periphery of the pregrout layer, and a capsule including a pregrout-hardening agent and a film with which the agent is covered, the capsule being interposed among the steel wires constituting the PC steel stranded wire. The capsule has a strength such that the capsule is not broken before tensioning the PC steel stranded wire but is broken by a tensile force during the tensioning. Also provided is a method for hardening the pregrout layer.

Abstract: A powder coating composition for PC strand coating which, when used for the coating of a PC strand, can advantageously form a coating film having an even thickness at low cost without causing uneven thickness or stringness is disclosed. The powder coating composition of this invention for PC strand coating is characterized by having a melt viscosity of 3,000-15,000 poise.

Abstract: Provided is a pregrouted PC steel material comprising a PC steel stranded wire composed of a plurality of steel wires, a pregrout layer disposed on the outer periphery of the PC steel stranded wire so as to accommodate the PC steel stranded wire, a sheath covering the outer periphery of the pregrout layer, and a capsule including a pregrout-hardening agent and a film with which the agent is covered, the capsule being interposed among the steel wires constituting the PC steel stranded wire. The capsule has a strength such that the capsule is not broken before tensioning the PC steel stranded wire but is broken by a tensile force during the tensioning. Also provided is a method for hardening the pregrout layer.

Abstract: There is provided a strand that can reduce the trouble in constructing an object to which compression force is applied by the strand and that can keep the construction cost down. A strand 1 is placed in a bore hole provided in a wall or roof surface, and is gripped by a wedge in a tensioned state so as to apply a tensile force to the wall or roof surface. The strand 1 of the present invention includes a pipe-shaped member (corrugated tube 11) made of metal, and a plurality of metal wires 12 arranged on the outer periphery of the corrugated tube 11. The metal wires 12 are arranged to surround the corrugated tube 11 on the cross section of the corrugated tube 11.

Abstract: A powder coating composition for PC strand coating which, when used for the coating of a PC strand, can advantageously form a coating film having an even thickness at low cost without causing uneven thickness or stringness is disclosed. The powder coating composition of this invention for PC strand coating is characterized by having a melt viscosity of 3,000-15,000 poise.

Abstract: There is provided a strand that can reduce the trouble in constructing an object to which compression force is applied by the strand and that can keep the construction cost down. A strand 1 is placed in a bore hole provided in a wall or roof surface, and is gripped by a wedge in a tensioned state so as to apply a tensile force to the wall or roof surface. The strand 1 of the present invention includes a pipe-shaped member (corrugated tube 11) made of metal, and a plurality of metal wires 12 arranged on the outer periphery of the corrugated tube 11. The metal wires 12 are arranged to surround the corrugated tube 11 on the cross section of the corrugated tube 11.

Abstract: A curable composition applied to the surface of a tendon for prestressed concrete contains at least an epoxy resin and a moisture-curing type curing agent. In the curable composition, the tensioning-permitting time L at 90° C. is at least 20 hours, and the number of days M required to cure at normal temperature is at most 1095 days. The curable composition for tendons for prestressed concrete according to the present invention permits complete prevention of corrosion without conducting injection of a grout into a sheath and can be used even when the curable composition is heated to a high temperature by heat generated upon hardening of concrete.

Abstract: A curable composition applied to the surface of a tendon for prestressed concrete contains at least an epoxy resin and a moisture-curing type curing agent. In the curable composition, the tensioning-permitting time L at 90° C. is at least 20 hours, and the number of days M required to cure at normal temperature is at most 1095 days. The curable composition for tendons for prestressed concrete according to the present invention permits complete prevention of corrosion without conducting injection of a grout into a sheath and can be used even when the curable composition is heated to a high temperature by heat generated upon hardening of concrete.

Abstract: A curable composition applied to the surface of a tendon for prestressed concrete contains at least an epoxy resin and a moisture-curing type curing agent. In the curable composition, the tensioning-permitting time L at 90° C. is at least 20 hours, and the number of days M required to cure at normal temperature is at most 1095 days. The curable composition for tendons for prestressed concrete according to the present invention permits complete prevention of corrosion without conducting injection of a grout into a sheath and can be used even when the curable composition is heated to a high temperature by heat generated upon hardening of concrete.