CN-224200306-U - Equal-strength steel truss reinforcing structure for structurally damaging PC box girder

CN224200306UCN 224200306 UCN224200306 UCN 224200306UCN-224200306-U

Abstract

The utility model relates to an equal-strength steel truss reinforcing structure for a structurally damaged PC box girder, and belongs to the technical field of building structure reinforcement. The steel truss structure comprises a steel truss with the same strength as a PC box girder, wherein the steel truss is of a cuboid space steel truss structure, a plane truss is arranged on the opposite surface of a web plate to the steel truss, and opposite-pull screw rods fix the plane truss and the steel truss on two sides of the web plate. The steel truss is located either inside or outside the web. And an anchor bolt and a steel gasket are further arranged on the opposite-pulling screw rod to strengthen and fix the steel truss and the plane truss respectively, so that the opposite-pulling screw rod is anchored. The opposite-pulling screw rods are arranged at the joint of each chord rod in the steel truss. The end part of the steel truss is provided with a steel-concrete transition connecting section which is fixed by a pair of pull screws, and the number of the pair of pull screws on the transition connecting section is determined according to the tensile force born by the steel truss chord member and the tensile force born by a single pair of pull screws. The utility model ensures smaller original structure damage and stronger reinforcement effect by arranging the equal-strength steel truss on the damaged box girder.

Inventors

YANG JIANFEI
YANG LIJUN
LIAO CHENG
DANG XUEXIN
GAO GUOFU
LUO YUHU

Assignees

甘肃省白银公路事业发展中心靖远公路段
重庆交通大学

Dates

Publication Date: 20260505
Application Date: 20250527

Claims (8)

1. A uniform-strength steel truss reinforcing structure for structurally damaging a PC box girder is characterized by being arranged on a web plate (11) of a section to be reinforced of the PC box girder (1), and comprising steel trusses (2) which are uniform in strength with the PC box girder (1), wherein the steel trusses (2) are fixed on the web plate (11) through opposite-pulling screws (3), the steel trusses (2) are of cuboid space steel trusses (2) structures, plane trusses (4) are arranged on opposite faces of the web plate (11) and the steel trusses (2), and the plane trusses (4) are connected with the steel trusses (2) through opposite-pulling screws (3) penetrating through the web plate (11) so as to fix the steel trusses (2).
2. The equal-strength steel truss reinforcing structure for structurally damaged PC box girders according to claim 1, characterized in that the steel truss (2) is located inside the web (11) of the PC box girder (1).
3. The equal-strength steel truss reinforcing structure for structurally damaged PC box girders according to claim 1, characterized in that the steel truss (2) is located outside the web (11) of the PC box girder (1).
4. The equal-strength steel truss reinforcing structure for the structurally damaged PC box girder, which is disclosed in claim 1, is characterized in that an anchor bolt (5) and a steel gasket (6) are further arranged on the opposite-pulling screw rod (3), the steel gasket (6) is positioned on one side of the steel truss (2) or the plane truss (4) close to the web plate (11) to strengthen and fix the steel truss (2) and the plane truss (4), and the anchor bolt (5) is positioned on one side of the steel truss (2) or the plane truss (4) far from the web plate (11) to anchor the opposite-pulling screw rod (3).
5. The equal-strength steel truss reinforcing structure for structurally damaged PC box girders according to claim 1, wherein the opposite-pulling screw rods (3) are arranged at the connection positions of the chord rods in the steel truss (2).
6. The equal-strength steel truss reinforcing structure for structurally damaged PC box girders according to claim 1, wherein the end part of the steel truss (2) is provided with a steel-concrete transition connection section (7), and the transition connection section (7) is fixed on the web plate (11) through the opposite-pulling screw rods (3).
7. The equal-strength steel truss reinforcing structure for structurally damaged PC box girders according to claim 6, wherein the number n=T 1 /T 2 ,T 1 of the counter-pulling screws (3) on the transition connection section (7) is the tensile force born by the chord members of the steel truss (2), and T 2 is the tensile force born by a single counter-pulling screw (3).
8. The equal-strength steel truss reinforcing structure for structurally damaged PC box girders according to claim 1, wherein the steel truss (2) is an eight-limb truss, a ten-limb truss or a twelve-limb truss.

Description

Equal-strength steel truss reinforcing structure for structurally damaging PC box girder Technical Field The utility model belongs to the technical field of building structure reinforcement, and relates to an equal-strength steel truss reinforcement structure for a structural damage PC box girder. Background Structural damage of a concrete structure means that penetrating cracks (crack width >0.3 mm) appear in the concrete, large-area peeling or layering occurs, reinforcing steel bars are exposed in a remarkable corrosion mode, the section loss rate exceeds 20%, and the bearing capacity is reduced to below 60% of a design value. The structural performance and the safety are reduced due to the damage, and huge economic loss and potential safety hazards are brought, so that attention is required to solve the structural damage problem of the prestressed concrete box girder. The reinforced concrete box girder can be integrally replaced by a single span after structural damage, but the prestressed concrete continuous girder or continuous rigid frame is difficult to be replaced by a single span due to longitudinal prestress, and only a comprehensive reinforcing method can be adopted. The traditional mode for reinforcing the structural damage of the prestressed concrete box girder mainly comprises four modes, namely a first mode for increasing the cross section, a second mode for reinforcing a bonded steel plate, wherein a layer of new concrete or prestressed concrete is added on the surface of an original girder to improve the bearing capacity and rigidity of the girder, a third mode for reinforcing the steel plate and the concrete by adopting a high-strength adhesive to bond the steel plate on the surface of the concrete girder, a third mode for reinforcing the external prestress, wherein the external prestress is applied to the girder body by arranging prestress ribs outside the girder body to generate bending moment and shearing force which are opposite to the load effect to reduce the stress in the girder body, and a fourth mode for reinforcing the bonded fiber composite material, wherein the fiber composite material is bonded on the surface of the girder body by using a special adhesive and bears a part of load to work together with the original structure. Although these reinforcement methods can reduce structural damage to the prestressed concrete box girder to some extent, there are corresponding problems. The first reinforcing method for increasing the cross section requires certain dismantling and processing of the original structure during construction, has larger damage to the original structure and can increase the dead weight of the structure, possibly has adverse effect on the foundation, the second reinforcing method for pasting the steel plate has higher requirements on pasting technology, the pasting quality is difficult to ensure, the steel plate is easy to rust and needs corresponding rust-proof processing, the third reinforcing method for external prestress has higher requirements on construction technology and needs to periodically check and maintain the corrosion prevention and anchoring conditions of external prestress ribs, and the fourth reinforcing method for pasting the fiber composite material has larger environmental influence on the bonding performance between the fiber composite material and the concrete, has long-term performance to be further researched and has relatively higher reinforcing cost. In addition, the method has common defects that prestress of the cracked concrete cannot be counted, local reinforcing effect is limited, and later disease estimation is difficult to estimate. Therefore, how to ensure that the damage to the original structure is less, the construction process is simpler, the reinforcement effect is more ensured, and the later maintenance cost and the cost are lower becomes the problem to be solved urgently by the technicians in the field. Disclosure of utility model In view of the above, the utility model aims to provide an equal-strength steel truss reinforcing structure for structurally damaging a PC box girder, and simultaneously, the equal-strength steel truss reinforcing structure ensures smaller original structural damage and stronger reinforcing effect. In order to achieve the above purpose, the present utility model provides the following technical solutions: the equal-strength steel truss reinforcing structure for the PC box girder structurally damaged is arranged on a web plate of a section to be reinforced of the PC box girder and comprises steel trusses which are equal in strength with the PC box girder, wherein the steel trusses are fixed on the web plate through opposite-pull screws, the steel trusses are of cuboid space steel truss structures, plane trusses are arranged on opposite faces of the web plate and are connected with the steel trusses through opposite-pull screws penetrating through the web plate, and accordingly fixing of the ste