Abstract: A shear beam-column connection includes a first beam, a first tapered bolt having a non-threaded portion and a threaded end portion, and a column including a first wedge slot block. The non-threaded portion of the first tapered bolt is fixedly secured, e.g., by welding, to the first beam. The wedge slot block includes a cavity for removably receiving the non-threaded portion of the first tapered bolt. The first wedge slot block is fixedly secured to the column, e.g., by welding. The first beam can be secured to the column by positioning the first beam adjacent the column such that the non-threaded portion of the bolt is inserted into the cavity. A nut can be threaded to the free end of the bolt to further secure the beam to the column.

Abstract: The system and method for connecting a square concrete-filled steel tubular column to a reinforced concrete footing includes a short steel pipe partially embedded in the footing, the pipe having a top end having flanges extending radially therefrom, the top end extending into a cavity in the footing having an elliptical top opening and circular base, the flanges extending above the base. An elliptical base plate is welded to the bottom of the tubular steel column, the base plate having a circular opening defined therein and a plurality of spaced flange slots depending therefrom. The bottom end of the column is lowered into the cavity, the elliptical base plate passing through the elliptical opening in the cavity, and the column is rotated 90° to interlock the flanges with the flange slots. The cavity is filled with concrete grout, and the square or rectangular steel column is filled with concrete.

Abstract: The system and method for connecting a square concrete-filled steel tubular column to a reinforced concrete footing includes a short steel pipe partially embedded in the footing, the pipe having a top end having flanges extending radially therefrom, the top end extending into a cavity in the footing having an elliptical top opening and circular base, the flanges extending above the base. An elliptical base plate is welded to the bottom of the tubular steel column, the base plate having a circular opening defined therein and a plurality of spaced flange slots depending therefrom. The bottom end of the column is lowered into the cavity, the elliptical base plate passing through the elliptical opening in the cavity, and the column is rotated 90° to interlock the flanges with the flange slots. The cavity is filled with concrete grout, and the square or rectangular steel column is filled with concrete.

Abstract: The hybrid post-installed anchor for concrete is a structural anchor for installation within a hole formed in concrete. The hybrid post-installed anchor for concrete includes an anchor rod and a plurality of anchor rings mounted on and encircling the anchor rod. Each anchor ring includes a cylindrical ring, having opposed open upper and lower ends, and a plurality of fins secured to an outer surface of the cylindrical ring. Each fin has a fixed edge, which is secured to the outer surface of the cylindrical ring, and a free edge. Each fin projects radially and upwardly, such that each fin is angled with respect to a common central axis of the anchor rod and each anchor ring when the anchor rings are mounted coaxially on the anchor rod. Alternatively, the fins may be formed integrally on the anchor rod, without separate cylindrical rings.

Abstract: The method of connecting a circular concrete-filled steel tubular column to a reinforced concrete footing provides a process for constructing a circular concrete-filled steel tubular column anchored in a reinforced concrete footing. A tubular member is partially embedded in a cavity formed in a block of reinforced concrete, such that a pair of flanges thereof is positioned adjacent to and above a base surface of the cavity. A steel tube is partially inserted into the cavity, such that rotation of the steel tube will cause the pair of flanges to interlock with a pair of slots at the lower end of the steel tube, locking the steel tube in place with respect to the tubular member and the block of reinforced concrete. The cavity is filled with concrete grout to secure the column, and the steel tube is filled with concrete to form the circular concrete-filled steel tubular column.

Abstract: The system and method for connecting a square concrete-filled steel tubular column to a reinforced concrete footing includes a short steel pipe partially embedded in the footing, the pipe having a top end having flanges extending radially therefrom, the top end extending into a cavity in the footing having an elliptical top opening and circular base, the flanges extending above the base. An elliptical base plate is welded to the bottom of the tubular steel column, the base plate having a circular opening defined therein and a plurality of spaced flange slots depending therefrom. The bottom end of the column is lowered into the cavity, the elliptical base plate passing through the elliptical opening in the cavity, and the column is rotated 90° to interlock the flanges with the flange slots. The cavity is filled with concrete grout, and the square or rectangular steel column is filled with concrete.

Abstract: A damped reinforced joint for a beam-column connection is provided for improving the resistance of steel-framed buildings against progressive collapse. Prestressing cables extend across each joint, and each prestressing cable is partially encased within a bent pipe. Each bent pipe may have multiple bends, forming a rippled or undulating shape. The prestressing cables strengthen the connections in the joints, and the bent pipes provide damping for dissipation of seismic energy and the like, thus improving resistance to earthquakes and other seismic, vibratory and/or shock events to the building frame.

Abstract: The fiber elements for soil stabilization include a combination of rigid and flexible fibers that are adapted to be added to soil in order to stabilize the soil to improve the geotechnical characteristics thereof. Each fiber element includes a rigid fiber having opposed first and second ends, at least the first end defining a first ring. A plurality of flexible fibers are attached to the first ring. When mixed with soil, the rigid fibers provide stiffness to the soil mass, and the flexible fibers provide deformability. For purposes of packaging, prior to addition to soil, the plurality of flexible fibers may be at least partially secured to one another by a water soluble material, such as a water soluble glue, water soluble thread or the like. A plurality of the fiber elements may be secured to one another by the water soluble material, forming a fiber module.

Abstract: The reinforced joint for a beam-column connection is provided for improving the resistance of steel-framed buildings against progressive collapse. Flange stiffening plates reinforce flanges of structural beams, with beam web stiffeners being attached to and extending between the flange stiffening plates. Additional column web stiffeners are attached to and extend between flanges of a structural column. A longitudinal cover stiffening plate is attached to the column stiffeners and the flange stiffening plates, extending across the joint and at least partially covering the beam web stiffeners. The reinforced joint between the structural beams and the structural column develops catenary action in the structural beams in the event of collapse.

Abstract: An integral dual module geopolymer building block includes an inner foam module for insulation and an outer dense tile surface on an outer side of the inner foam module for weather protection. The outer porous module comprises a geopolymer paste including sodium silicate and sodium hydroxide flakes dissolved in the sodium silicate to form an activated solution and adding calcined kaolin clay to the activated solution to form a geopolymer paste. A first relatively dense tile layer has a thickness of about 0.5 cm to 1.5 cm. A second geopolymer layer made from a second mass of paste mixed with hydrogen peroxide forms a geopolymer foam having a thickness of between 5 cm and 15 cm.

Abstract: The method of connecting a circular concrete-filled steel tubular column to a reinforced concrete footing provides a process for constructing a circular concrete-filled steel tubular column anchored in a reinforced concrete footing. A tubular member is partially embedded in a cavity formed in a block of reinforced concrete, such that a pair of flanges thereof is positioned adjacent to and above a base surface of the cavity. A steel tube is partially inserted into the cavity, such that rotation of the steel tube will cause the pair of flanges to interlock with a pair of slots at the lower end of the steel tube, locking the steel tube in place with respect to the tubular member and the block of reinforced concrete. The cavity is filled with concrete grout to secure the column, and the steel tube is filled with concrete to form the circular concrete-filled steel tubular column.

Abstract: The multi-leg fiber reinforced concrete is concrete in which fibers have been embedded to prevent the concrete from being fractured due to cracks developing therein. Each fiber has multiple legs, defining two and three dimensional structures. At least one fiber is embedded in a volume of concrete, where the at least one fiber has at least first and second legs respectively extending along first and second directions. The first and second directions are angularly oriented with respect to one another between 45° and 135°, with each of the first and second legs having a free end and a fixed end. Each free end has a substantially Z-shaped contour. The fixed ends of the first and second legs may be joined together to define a two-dimensional fiber structure. The at least one fiber may be partially coated with a polymeric material, such as polypropylene.

Abstract: The multi-leg fiber reinforced concrete is concrete in which fibers have been embedded to prevent the concrete from being fractured due to cracks developing therein. Each fiber has multiple legs, defining two and three dimensional structures. At least one fiber is embedded in a volume of concrete, where the at least one fiber has at least first and second legs respectively extending along first and second directions. The first and second directions are angularly oriented with respect to one another between 45° and 135°, with each of the first and second legs having a free end and a fixed end. Each free end has a substantially Z-shaped contour. The fixed ends of the first and second legs may be joined together to define a two-dimensional fiber structure. The at least one fiber may be partially coated with a polymeric material, such as polypropylene.

Abstract: The multi-leg fiber reinforced concrete is concrete in which fibers have been embedded to prevent the concrete from being fractured due to cracks developing therein. Each fiber has multiple legs, defining two and three dimensional structures. At least one fiber is embedded in a volume of concrete, where the at least one fiber has at least first and second legs respectively extending along first and second directions. The first and second directions are angularly oriented with respect to one another between 45° and 135°, with each of the first and second legs having a free end and a fixed end. Each free end has a substantially Z-shaped contour. The fixed ends of the first and second legs may be joined together to define a two-dimensional fiber structure. The at least one fiber may be partially coated with a polymeric material, such as polypropylene.

Abstract: The method of connecting a circular concrete-filled steel tubular column to a reinforced concrete footing provides a process for constructing a circular concrete-filled steel tubular column anchored in a reinforced concrete footing. A tubular member is partially embedded in a cavity formed in a block of reinforced concrete, such that a pair of flanges thereof is positioned adjacent to and above a base surface of the cavity. A steel tube is partially inserted into the cavity, such that rotation of the steel tube will cause the pair of flanges to interlock with a pair of slots at the lower end of the steel tube, locking the steel tube in place with respect to the tubular member and the block of reinforced concrete. The cavity is filled with concrete grout to secure the column, and the steel tube is filled with concrete to form the circular concrete-filled steel tubular column.

Abstract: The multi-leg fiber reinforced concrete is concrete in which fibers have been embedded to prevent the concrete from being fractured due to cracks developing therein. Each fiber has multiple legs, defining two and three dimensional structures. At least one fiber is embedded in a volume of concrete, where the at least one fiber has at least first and second legs respectively extending along first and second directions. The first and second directions are angularly oriented with respect to one another between 45° and 135°, with each of the first and second legs having a free end and a fixed end. Each free end has a substantially Z-shaped contour. The fixed ends of the first and second legs may be joined together to define a two-dimensional fiber structure. The at least one fiber may be partially coated with a polymeric material, such as polypropylene.

Abstract: The system for constructing a retaining wall can be used to construct a segmental retaining wall for retaining earth, on either side, at two different levels. The system includes a plurality of blocks. Each block has laterally opposed first and second end portions, a central portion and a neck portion. The central portion is positioned between the first end portion and the neck portion, and the neck portion is positioned between the second end portion and the central portion. The central portion has a longitudinal length less than a longitudinal length of the first end portion, the second end portion has a longitudinal length less than the longitudinal length of the central portion, and the neck portion has a longitudinal length less than the longitudinal length of the second end portion. A plurality of pegs can vertically interlock adjacent blocks. Tie connectors can connect the blocks to an external pipe.

Abstract: The strengthening system for beam-column connections in steel frame buildings to resist progressive collapse helps to mitigate progressive collapse in the event of accidental column loss by using a system of rippled steel plates reinforcing the beam-column connection. Various configurations of rippled steel plates are provided to connect in-plane and transverse beams at a joint. In the event of severe damage caused to a column of a steel framed building, the upper joints of the damaged column undergo downward movement. The rippled plates at the joint straighten during the initial downward movement, and resist further downward movement after complete straightening of the ripples. This helps in the development of catenary action in steel beams. The proposed system is simple, fast to construct, demountable, and easy to repair/replace after damage caused by blast loads.

Abstract: An interlocking and insulated construction block includes a first pair of parallel, opposing sides and a second pair of parallel, opposing sides extending normal to the first pair of opposing sides. At least one cavity or recess extends through the construction block and includes a first volume of thermal insulation material. One or both sides of the first pair of opposing sides includes a pair of staggered engaging members or a pair of staggered receiving members configured to engage or lock with a mating pair of engaging members or receiving members of another insulated construction block. A plurality of different embodiments of the interlocking and insulated construction blocks may be provided in a set, and provide for mortar-less construction of walls due to their interlocking nature.