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 conduit segment casting mold system includes at least one inner mold; at least one outer mold configured as at least two outer mold sections of opposed shapes that define a cavity between the at least two outer mold sections that is sized to at least partially enclose the at least one inner mold, each of the at least two outer mold sections including a respective mating surface, each of the at least two outer mold sections including at least one hole sized to receive a cable, and the at least one hole of a particular one of the at least two outer mold sections is aligned with the at least one hole of another particular one of the at least two outer mold sections when the mating surfaces of the particular one and the another particular one of the at least two outer mold sections are mated; and a mold base.

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 conduit segment casting mold system includes at least one inner mold; at least one outer mold configured as at least two outer mold sections of opposed shapes that define a cavity between the at least two outer mold sections that is sized to at least partially enclose the at least one inner mold, each of the at least two outer mold sections including a respective mating surface, each of the at least two outer mold sections including at least one hole sized to receive a cable, and the at least one hole of a particular one of the at least two outer mold sections is aligned with the at least one hole of another particular one of the at least two outer mold sections when the mating surfaces of the particular one and the another particular one of the at least two outer mold sections are mated; and a mold base.

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.

A method of preparing a ceramic fabric for use in a ceramic matrix composite includes transforming a ceramic tow from a first tow geometry to a second tow geometry, thereby reducing a first dimension of the ceramic tow and increasing a second dimension of the ceramic tow orthogonal to the first dimension to produce a flattened tow. The method includes weaving or braiding the flattened ceramic tow to form a ceramic fabric.

A method of preparing a ceramic fabric for use in a ceramic matrix composite includes transforming a ceramic tow from a first tow geometry to a second tow geometry, thereby reducing a first dimension of the ceramic tow and increasing a second dimension of the ceramic tow orthogonal to the first dimension to produce a flattened tow. The method includes weaving or braiding the flattened ceramic tow to form a ceramic fabric.