Steel plate externally-rived stengthening method for reinforced concrete structure and its special-purpose rivet

[0085] Specific embodiment 1 is a typical rivet steel reinforcement method 1: using rivet steel reinforcement method to increase the main reinforcement of the beam

[0086] As shown in Figures 8 and 9, the size of the rectangular cross-section lintel is: 120mm (height) × 240mm (width), the span is 2m, the design requires the reinforcement at the bottom of the beam to be 3φ12, and the actual reinforcement is only 2φ6. Now, a 6mm strip is riveted at the bottom Reinforced by 80mm steel slats.

[0087] Steel slat design maximum tensile strength:

[0088] 6mm×(80mm-14mm)×210N / mm 2 =83.16kN, where 14mm is the hole diameter of the steel plate.

[0089] The number of rivets in the 1 / 4 length range at both ends of the steel strip:

[0090] 83.16kN / 20kN=4.15 (pieces), 5 pieces are actually selected, that is, 1 rivet is arranged in a 10cm arrangement, and the design tensile force of each rivet is 20kN.

[0091] The rivets in the middle of the steel strips are arranged according to

[0093] Example 2 is a typical reinforcement method 2: using riveted steel reinforcement method to increase the stirrups of the beam

[0094] As shown in Figures 10, 11, and 12, a beam with a rectangular cross-section has a cross-sectional size of 240mm (height) × 120mm (width) and a span of 2m. According to the design requirements, it is necessary to add stirrups within 60cm on both sides of the beam. The amount of added stirrups is 5 φ10 steel bars with a spacing of 150mm to improve the shear resistance of the beam. Now it is reinforced by riveting five 3mm×50mm parallel U-shaped hoop slats at the beam end. The maximum tensile force of the steel slats is:

[0095] 3mm×(50mm-12mm)×210N / mm 2 =23.9kN, where 12mm is the aperture size of the steel plate.

[0096] The number of rivets in the 1 / 4 length range of both ends of the steel plate: 23.9kN / 20kN=1.2 (pieces), actually choose 2, where 20kN is the tensile force of a single rivet.

[0097] The total length of the U-shaped