A system and method for applying tension to a reinforcement member is provided. The system includes a gripping device, a tension device, and a tension application sub-system. The gripping device includes first and second attachments. Each attachment retains a respective end of the reinforcement member with sufficient friction force based on a predetermined tension to be applied to the reinforcement member. The tension device includes first and second tension tubes configured to removably receive and hold the first and second attachments, respectively. The tension application sub-system has first and second tension application apparatuses and first and second coupling devices. The first and second coupling devices couple the first and second tension tubes to the first and second tension application apparatuses, respectively. At least one of the first and second tension application apparatuses creates and controllably adjusts a tension load within the reinforcement member.

A process for molding prestressed slender and corrugated surface concrete bars to be used subsequently in casting concrete pieces or structures includes, placing them conveniently inside said pieces or structures, in order to also prestress said pieces or structures by gripping and relieving the tensions contained in said bar from the middle section of its longitudinal length.

A system and method for allowing components to attach to a pre-cast pre-stressed concrete structure is provided. The system includes a first attachment part and a second attachment part. The first attachment part has a first body. The first body has a first concrete structure facing side and a first plurality of attachment members extending from the concrete structure facing side. The second attachment part has a second body. The second body has a second concrete structure facing side and a second plurality of attachment members extending from the concrete structure facing side. The first and second attachment parts are spaced apart forming a compressible junction therebetween. The pre-cast, pre-stressed concrete structure is formed from uncured cement, at least of a portion of the first and second attachment members being embedded in the pre-cast, pre-stressed concrete structure.

System and method allows a component to attach to a pre-cast, pre-stressed concrete structure. The system includes a first attachment part, a pre-cast, pre-stressed concrete member and first and second reinforcing members. A first body of a first attachment part has a first concrete structure facing side and a first plurality of attachment members. The pre-cast, pre-stressed concrete member is formed from uncured cement. At least a portion of the attachment members are embedded within the pre-cast, pre-stressed concrete member. The first reinforcing member is placed under a first tension load and the second reinforcing member is placed under a second tension load. The pre-cast, pre-stressed concrete member is formed from uncured cement poured about at least a portion of the first and second reinforcing members while the first and second reinforcing members are under stress.

A self-stressing shape memory alloy (SMA)/fiber reinforced polymer (FRP) composite patch is disclosed that can be used to repair cracked steel members or other civil infrastructures. Prestressed carbon FRP (CFRP) patches have emerged as a promising alternative to traditional methods of repair. However, prestressing these patches typically requires heavy and complex fixtures, which is impractical in many applications. This disclosure describes a new approach in which the prestressing force is applied by restraining the shape memory effect of nickel titanium niobium alloy (NiTiNb) SMA wires. The wires are subsequently embedded in an FRP overlay patch. This method overcomes the practical challenges associated with conventional prestressing.

A self-stressing shape memory alloy (SMA)/fiber reinforced polymer (FRP) composite patch is disclosed that can be used to repair cracked steel members or other civil infrastructures. Prestressed carbon FRP (CFRP) patches have emerged as a promising alternative to traditional methods of repair. However, prestressing these patches typically requires heavy and complex fixtures, which is impractical in many applications. This disclosure describes a new approach in which the prestressing force is applied by restraining the shape memory effect of nickel titanium niobium alloy (NiTiNb) SMA wires. The wires are subsequently embedded in an FRP overlay patch. This method overcomes the practical challenges associated with conventional prestressing.

A system for coating reinforcing fiber of a composite component is provided, The system includes a frame including at least one contact location for contacting the reinforcing fiber and a movement mechanism including an actuator. The movement mechanism is operably coupled to the frame to induce movement of the reinforcing fiber relative to the frame. Methods are also provided for coating such a fiber.

A pre-stressed cast concrete structure comprises embedded fibrous reinforcing tendons in tension. The fibrous reinforcing tendons each comprises a plurality of continuous non-metallic fibers extending substantially the entire length of the tendon. A system for pre-stressing a cast concrete structure includes a mold for containing concrete, fibrous reinforcing tendons, chuck assemblies associated with the reinforcing tendons and a tensioning mechanism. When cured, the concrete rigidly surrounds the reinforcing tendons such that the reinforcing tendons are maintained in tension. The chuck assemblies have a plurality of jaws that contact the reinforcing tendons in a manner to resist damage to the fibers.

The continuous fiber reinforcing material tension apparatus includes a pressing body that presses a sleeve to a side of a fixed structure and contains a hollow portion, in which a wedge body is allowed to reciprocate along a continuous fiber reinforcing material, a cylindrical bracket located in an opposite side of the sleeve from the pressing body and having an inner wall surface on which a projection is formed, a columnar rotary jig that is allowed to reciprocate inside the bracket, that engages with an end face of the wedge body, that has a spiral key groove that engages with a key, and that applies rotative force around an axis of the continuous fiber reinforcing material, and a piston that presses an end face of the rotary jig to a side of the fixed structure.

In the process of the invention for producing concrete components, carbon fibers which have been prestressed by means of tensile stress or tensile-stressable fibers of at least one textile structure comprising carbon fibers are embedded in a concrete matrix. At least one textile structure comprising carbon fiber bundles is laid in a mold. The carbon fiber bundles are inserted, in each case at a distance from one another, into two accommodation elements which are arranged at two diametrical end faces of the mold and can be connected on the end walls of the mold or thereto through openings so that hollow spaces within the accommodation element are filled with a rapid-curing viscous composition having a mineral basis or a rapid-curing polymer. After curing of the composition or of the polymer, tensile forces act on one or both accommodation element(s) in the longitudinal direction of the carbon fiber bundles at at least one end face by means of a tensioning device. While the tensile forces are acting, the interior of the mold is subsequently filled completely with viscous concrete. After curing of the concrete, the tensile forces on the prestressed carbon fiber bundles are largely transferred to the cured concrete and the concrete component can then be removed from the mold.