This method is suitable for the strengthening of concrete or timber structures by applying prestressed Carbon FRP or Glass FRP lamella. At least one groove is cut into the concrete or timber structure along the direction in which the concrete or timber structure is to be strengthened. The grooves are filled with epoxy resin and a layer of epoxy resin is put onto the entire section to be equipped with the CRFP or GFRP lamella. The lamella is prestressed and anchored at both ends. U-shaped brackets are then being put over the two end sections of the CFRP or GFRP lamella by inserting and submerging its both U-legs into holes filled with resin as well. These holding brackets are then tightly pressed onto the CFRP or GFRP lamella to prevent cracking or fracture of the concrete or timber and bending away of the extremities of the CFRP or GFRP lamella.

Disclosed invention comprises innovations in the fabrication process and the associated design methodology for producing refined prestressed concrete elements/components. The innovations disclosed are fabrication using multiple stages, the use of ultra high strength materials for only critical subcomponents, utilizing thinner sections made of ultra high strength materials, and a unique method of inducing and controlling camber. The embodiments of this invention enable the accelerated construction of concrete structures that are both durable and cost effective. This disclosure demonstrates the significant improvements to the prior art in the areas of durability, constructability, and cost reduction for prestressed concrete components. The embodiments presented in this disclosure are for bridge superstructure applications.

There is provided a method of prestressing a beam-column joint with an appropriate ratio among the magnitudes of compression in the directions of X, Y, and Z axes. The method introduces prestress in a beam-column joint with a tensile introducing force generated by tensionally anchoring prestressing tendons that are arranged in PC beams extending along two horizontal directions (or X axis and Y axis) and PC columns extending along the vertical direction (or Z axis) and passed through the beam-column joint to bring the beam-column joint in triaxial compression, the prestress being introduced such that a diagonal tensile force T generated by an input shear force due to a seismic load of an extremely great earthquake that may occur very rarely will be cancelled completely or partially so as not to allow diagonal cracks to occur. The ratio of the prestresses introduced in the directions of the respective axes satisfies the following equation (1):
σx:σy:σz=1:1:0.3−0.9   (1)
where σx, σy, and σz are prestresses introduced in the directions of the X axis, the Y axis, and the Z axis respectively.

There is provided a method of introducing prestress into a beam-column joint of PC construction to make it into a triaxially compressed state, in which the beam-column joint is made into a triaxial compression state and reasonable prestress is introduced into cross section areas of the ends of the members forming the beam-column joint.

A tensile introducing force is generated by tensionally anchoring PC cables passed through the beam-column joint to introduce prestresses into the cross section areas of the ends of the members forming the beam-column joints in respective axial directions to make triaxial compression state, to satisfy the following conditions (1) and (2): (1) no tensile strength is generated, with respect to long term design load, in cross-section areas of the members forming the end of the beam and the end of the column, which ends are in contact with the beam-column joint; and (2) upon occurring of extremely large scale earthquake (very rarely occurred earthquake), in the beam-column joint, no generation of diagonal cracks is allowed to be generated but diagonal tensile stress intensity caused due to shear force inputted by seismic load is made less than allowable tensile stress intensity of concrete.

There is provided a method of introducing prestress into a beam-column joint of PC construction to make it into a triaxially compressed state, in which the beam-column joint is made into a triaxial compression state and reasonable prestress is introduced into cross section areas of the ends of the members forming the beam-column joint.

A tensile introducing force is generated by tensionally anchoring PC cables passed through the beam-column joint to introduce prestresses into the cross section areas of the ends of the members forming the beam-column joints in respective axial directions to make triaxial compression state, to satisfy the following conditions (1) and (2): (1) no tensile strength is generated, with respect to long term design load, in cross-section areas of the members forming the end of the beam and the end of the column, which ends are in contact with the beam-column joint; and (2) upon occurring of extremely large scale earthquake (very rarely occurred earthquake), in the beam-column joint, no generation of diagonal cracks is allowed to be generated but diagonal tensile stress intensity caused due to shear force inputted by seismic load is made less than allowable tensile stress intensity of concrete.

There is proposed a reinforced concrete structure comprising a reinforcement assembly embedded therein, the reinforcement assembly including first and second lengths of chain, wherein the first and second lengths of chain being pretensionable prior to forming the concrete structure. The reinforcement assembly includes pretensionable member/s and/or resiliently deformable member/s intermediate of at least one tetherable end of the lengths of chain and a mounting block or link member.

There is provided a method of prestressing a beam-column joint with an appropriate ratio among the magnitudes of compression in the directions of X, Y, and Z axes. The method introduces prestress in a beam-column joint with a tensile introducing force generated by tensionally anchoring prestressing tendons that are arranged in PC beams extending along two horizontal directions (or X axis and Y axis) and PC columns extending along the vertical direction (or Z axis) and passed through the beam-column joint to bring the beam-column joint in triaxial compression, the prestress being introduced such that a diagonal tensile force T generated by an input shear force due to a seismic load of an extremely great earthquake that may occur very rarely will be cancelled completely or partially so as not to allow diagonal cracks to occur. The ratio of the prestresses introduced in the directions of the respective axes satisfies the following equation (1):

x:y:z=1:1:0.30.9 (1)

where x, y, and z are prestresses introduced in the directions of the X axis, the Y axis, and the Z axis respectively.

A structural assembly utilizing a reinforced concrete support element with a flexibly-braided reinforcement sleeve and a cable system for building structures. The reinforced concrete BMASS element has an approximately cylindrical shape and includes a substantially solid concrete core. An outer reinforcement sleeve with a flexible multi-axially braided configuration is embedded on the perimeter, and an inner reinforcement sleeve is embedded within the outer sleeve. A cable tension system connected between the ends of the BMASS element transmits tensile force from the cable to the BMASS element. The structural assembly can be configured as a beam or a column. In a beam configuration, the tensioned cable can also provide beam curvature and greater strength. A multi-cable embodiment includes a second cable, providing additional strength and greater ability to control curvature. One or more of the braces may include an adjustable arm. The tension may be adjusted manually, or remotely.

A structural assembly utilizing a reinforced concrete support element with a flexibly-braided reinforcement sleeve and a cable system for building structures. The reinforced concrete BMASS element has an approximately cylindrical shape and includes a substantially solid concrete core. An outer reinforcement sleeve with a flexible multi-axially braided configuration is embedded on the perimeter, and an inner reinforcement sleeve is embedded within the outer sleeve. A cable tension system connected between the ends of the BMASS element transmits tensile force from the cable to the BMASS element. The structural assembly can be configured as a beam or a column. In a beam configuration, the tensioned cable can also provide beam curvature and greater strength. A multi-cable embodiment includes a second cable, providing additional strength and greater ability to control curvature. One or more of the braces may include an adjustable arm. The tension may be adjusted manually, or remotely.

The present disclosure relates to the technical field of assembled concrete frame structures, and discloses a prestressed assembled concrete frame-joint connecting structure and constructing method thereof. The present disclosure includes a prefabricated concrete column, a prefabricated concrete superposed beam, a composite slab, a post-tensioned prestressing tendon that connects the prefabricated concrete column and the prefabricated concrete superposed beam, a bending-resistant energy consuming steel bar and a shearing-resistant high-strength steel bar.