A double corrugated tooth FRP plate prestressed connection node and construction method

Abstract

The present invention discloses a double-corrugated-tooth FRP plate prestressed connection node and a construction method. Two through-length corrugated-tooth plates are provided at the ends of two FRP plates. The two corrugated-tooth plates are respectively located on the upper and lower surfaces of the FRP plates. Corrugated teeth are provided at the contact points with the upper and lower surfaces of the FRP plates. Pre-pressure is applied to the corrugated-tooth plates at the ends of the two FRP plates. The corrugated-tooth plates deform the FRP plates under the action of pressure. The deformed FRP plates fit tightly with the upper and lower corrugated-tooth plates. The pre-pressure is kept unchanged, and the fastening system is installed. After the external force is subsequently removed, pre-stress is established in the FRP plates and the corrugated-tooth plates, forming a double-corrugated-tooth FRP plate prestressed connection node. The connection node of the present invention has high strength and node efficiency, is convenient to construct, and is reliable. The connection method can be used to perform one-way extension and multi-directional connection of FRP profiles, and the corrugated-tooth plates can also be externally designed to adapt to operations such as bolt connection and welding.

Description

Technical Field

[0001] The invention belongs to the field of civil engineering and transportation, and relates to a double-corrugated tooth FRP plate prestressed connection node and a construction method. Background Art

[0002] FRP has the advantages of light weight, high specific strength, excellent durability, good self-healing performance, strong designability, heat insulation, non-magnetic, small thermal expansion coefficient and low comprehensive cost over the entire life cycle. It is widely favored at home and abroad.

[0003] FRP plates are formed by mixing continuous fibers and resin matrix in a certain proportion and undergoing a certain molding process, and are widely used in building structures and bridge structures. However, for a long time in the past, in general-purpose buildings, the use of composite materials as the main load-bearing components was still rare, and the proportion in engineering construction was still relatively small. The reason is that, on the one hand, the direct cost of composite material structure buildings is high; on the other hand, and most importantly, the composite material structure is restricted by technical factors of node connection, and the lack of high-performance composite material nodes also affects the application of composite material structures in the field of civil engineering and transportation.

[0004] Therefore, a new FRP plate connection node is needed to solve the above problems. Summary of the invention

[0005] Purpose of the invention: The present invention aims at the bottleneck of FRP plate connection nodes in the prior art and provides a double-corrugated tooth FRP plate prestressed connection node and a construction method with high connection efficiency and large bearing capacity.

[0006] In order to achieve the above object, the present invention adopts the following technical solution:

[0007] A double-corrugated FRP plate prestressed connection node, comprising a first FRP plate and a second FRP plate to be connected;

[0008] The connecting ends of the FRP plate 1 and the FRP plate 2 are provided with two full-length corrugated tooth plates, the corrugated tooth plates including corrugated tooth plate 1 and corrugated tooth plate 2, which are respectively located on the upper and lower surfaces of the FRP plate 1 and the FRP plate 2;

[0009] The contact between the corrugated tooth plate and the FRP plate 1 and the FRP plate 2 is provided with corrugated teeth, the shape, size and number of the corrugated teeth of the corrugated tooth plate 1 and the corrugated tooth plate 2 are the same, and can form a bite, and the corrugated tooth plate 1 and the corrugated tooth plate 2 are provided with a plurality of internal threaded holes on both sides along the length direction, and the size, hole spacing and vertical distance to the edge of the corrugated tooth plate of each internal threaded hole are the same;

[0010] The corrugated tooth plate 1 and the corrugated tooth plate 2 are pre-stress plates. Under the action of pressure, the corrugated tooth plate 1 and the corrugated tooth plate 2 cause the FRP plate 1 and the FRP plate 2 to deform. The deformed FRP plate 1 and the FRP plate 2 fit tightly with the two corrugated tooth plates. Keeping the pre-stress unchanged, a fastening system is installed on the corrugated tooth plate 1 and the corrugated tooth plate 2. The fastening system consists of a plurality of steel bars and high-strength bolts. Two bolt holes are provided on each of the steel bars, and they correspond one to one with the internal threaded holes on the two side surfaces of the two corrugated tooth plates along the length direction. The angle between any two adjacent steel bars is 45°. After the external force is removed, prestress is established in the FRP plate 1, the FRP plate 2 and the two corrugated tooth plates to form a prestressed connection node of a double corrugated tooth FRP plate.

[0011] Furthermore, the number of steel bars of the fastening system on both sides of the corrugated tooth plate 1 and the corrugated tooth plate 2 is not less than 19.

[0012] Furthermore, in order to ensure the efficiency of the fastening system in establishing prestress in the node and reduce prestress loss, the diameter of the bolt hole on the steel bar is 0.03 mm larger than the diameter of the high-strength bolt.

[0013] Furthermore, chamfers are provided at the contact points between the plate edges of the two corrugated tooth plates and the FRP plate 1 and the FRP plate 2 in the width direction to prevent damage to the FRP plates caused by stress concentration.

[0014] Furthermore, the material of the corrugated tooth plate can be steel, aluminum alloy or other materials with plastic deformation characteristics.

[0015] The above-mentioned construction method of a double-corrugated FRP plate prestressed connection node comprises the following steps:

[0016] 1) Place the corrugated tooth plate 1 and the corrugated tooth plate 2 on the upper and lower surfaces of the FRP plate 1 and the FRP plate 2 respectively, with the corrugated tooth surfaces of the two corrugated tooth plates facing the FRP plate 1 and the FRP plate 2;

[0017] 2) Apply uniform pressure, and when the straight section of the corrugated tooth plate with corrugated tooth surface is tightly fitted with FRP plate 1 and FRP plate 2, stop applying pressure and keep the pressure constant;

[0018] 3) Install the fastening system, which is composed of a number of steel bars and high-strength bolts, and embed the high-strength bolts in the fastening system into a number of corresponding internal threaded holes provided on both sides of the corrugated tooth plate 1 and the corrugated tooth plate 2 along the length direction;

[0019] 4) The external force is removed, and prestress is established in the FRP plate 1, the FRP plate 2 and the two corrugated tooth plates to form a prestressed connection node of the double corrugated tooth FRP plates.

[0020] Beneficial effects:

[0021] 1. The present invention greatly improves the node bearing capacity and gives full play to the tensile strength of FRP by establishing prestress between the corrugated tooth plate and the FRP plate; compared with traditional FRP plate adhesive joints and bolt joints, the node bearing capacity and node efficiency of the double corrugated tooth FRP plate prestressed node are significantly improved.

[0022] 2. The advantages of adjacent steel bars arranged along ±45° in the fastening system of the present invention are: full use is made of the stability of triangular force, so that the design cross-section of the steel bar can be as small as possible; the design thickness can be as thin as possible; compared with the fastening method of arranging large-diameter steel bolts on the surface of the corrugated tooth plate, it saves more materials, realizes the lightweight design of the connection node, and reduces the prestress loss in the node.

[0023] 3. The connection node of the present invention has high strength and node efficiency, and is convenient and reliable to construct. The connection method can be used to extend FRP profiles in one direction and connect them in multiple directions, and the corrugated tooth plate can also be designed and processed externally to adapt to bolt connection, welding and other operations. Therefore, the node can be used in structures such as trusses, grids and lattice columns containing composite materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the connection between the FRP plate and the corrugated tooth plate in Example 1 of the present invention;

[0025] Figure 2 This is a schematic diagram of prestressing in Example 1 of the present invention;

[0026] Figure 3 This is a schematic diagram of the installation and fastening system in Example 1 of the present invention;

[0027] Figure 4 for Figure 3 A top view of

[0028] Figure 5 for Figure 4 1-1 cross-sectional view;

[0029] Figure 6 It is a construction method flow chart of the prestressed connection method of the double-corrugated FRP plate of the present invention;

[0030] Figure 7 This is a schematic diagram of the connection between the FRP plate, the steel plate and the corrugated tooth plate in Example 2 of the present invention;

[0031] Figure 8 This is a schematic diagram of prestressing in Example 2 of the present invention;

[0032] Fig. 9 This is a schematic diagram of the installation and fastening system in Example 2 of the present invention;

[0033] Fig.10 for Fig. 9 A top view of

[0034] Fig.11 for Fig.10 1-1 cross-sectional view. DETAILED DESCRIPTION

[0035] The technical solution of the entire invention is described in detail below in conjunction with the accompanying drawings and specific implementation methods of the present invention.

[0036] Example 1

[0037] See also Figure 1-5 As shown, the double corrugated tooth FRP plate prestressed connection node of the present invention, wherein two through-length corrugated tooth plates 1 and 2 are provided at the ends of FRP plates 13 and 24, and the corrugated tooth plates 1 and 2 are respectively located on the upper and lower surfaces of FRP plates 13 and 24, and corrugated teeth are provided at the contact points between the corrugated tooth plates 1 and 2 and FRP plates 13 and 24, and the shapes, sizes and numbers of the corrugated teeth of the corrugated tooth plates 1 and 2 are the same and can form a bite, and the corrugated tooth plates 1 and 2 are provided with a plurality of internal threaded holes on both sides along the length direction. The corrugated tooth plates 1 and 2 are provided with chamfers with a radius of not less than 3 mm along the width direction of the plate edges. FRP (Fiber Reinforced Polymer, referred to as FRP) is a fiber reinforced composite material, which is a high-tech material formed by mixing continuous fibers and resin matrix in a certain proportion and compounding through a certain process. Internal threaded holes refer to internal threaded holes with a depth of not less than 15 mm and a number of not less than 3, which are set on the corrugated tooth plate by a special hole-opening tool.

[0038] Pre-stress is applied to the corrugated tooth plate 1 and corrugated tooth plate 2 at the ends of the two FRP plates 13 and 24. The corrugated tooth plate 1 and corrugated tooth plate 2 cause the two FRP plates 13 and 24 to deform under the pressure. The two deformed FRP plates 13 and 24 are tightly fitted with the upper and lower corrugated tooth plates 1 and 2. The pre-stress is kept unchanged. The fastening system 5 is installed, and then the external force is removed to achieve the purpose of establishing prestress in the FRP plates and the corrugated tooth plates, and form a double corrugated tooth FRP plate prestressed node. The fastening system 5 is composed of a number of steel bars and high-strength bolts, wherein each steel bar is provided with two bolt holes, which correspond to the internal thread holes on the two sides of the two corrugated tooth plates along the length direction. The angle between any two adjacent steel bars is 45°. In order to ensure the efficiency of the fastening system in establishing prestress in the node and reduce the prestress loss, the diameter of the bolt hole on the steel bar is 0.03mm larger than the diameter of the high-strength bolt. Furthermore, the number of steel bars of the fastening system 5 on both sides of the two corrugated tooth plates 1 and 2 is not less than 19.

[0039] like Figure 6 As shown, a construction method of a double corrugated tooth FRP plate prestressed connection method comprises the following steps:

[0040] First, place the corrugated tooth plate 2 on the static platform plate surface of the press, place two FRP plates 13 and 24 on the corrugated tooth plate 2, and straighten them, and place another corrugated tooth plate 1 on the two FRP plates 13 and 24. The contact points between the two corrugated tooth plates 11 and 22 and the upper and lower surfaces of the FRP plates 13 and 24 are provided with corrugated teeth;

[0041] Secondly, a pre-pressure is applied to the corrugated tooth plates 1 and 2 at the ends of the two FRP plates 1 and 2. The two corrugated tooth plates 1 and 2 deform the FRP plates 1 and 2 under the pressure. The deformed FRP plates 1 and 2 fit closely with the upper and lower corrugated tooth plates 1 and 2, and the pre-pressure is kept unchanged.

[0042] Third, install the fastening system 5, which is composed of a plurality of steel bars and high-strength bolts, and embed the high-strength bolts in the fastening system into a plurality of corresponding internal threaded holes provided on both sides of the two corrugated tooth plates along the length direction;

[0043] Fourth, the external force is removed, and prestress is established in the two FRP plates 1 3, FRP plate 2 4 and the corrugated tooth plate 1 1, corrugated tooth plate 2 2, and the prestressed connection node of the double corrugated tooth FRP plate is completed.

[0044] Example 2

[0045] See also Figure 7-11 As shown;

[0046] Except for the following differences from Example 1, the other parts are the same; the connection node includes the FRP plate 3 6 and the steel plate 7 to be connected; the corrugated tooth plate 1, the corrugated tooth plate 2 and the FRP plate 3 6 are provided with corrugated teeth at the contact point, and the contact point with the steel plate 7 is a straight section and is provided with Figure 8 The bolt holes shown in the figure, wherein the corresponding positions of the steel plate 7 are also provided with bolt holes. After the fastening system 5 is installed, the high-strength bolts 8 are embedded in the bolt holes corresponding to the corrugated tooth plate 1, the corrugated tooth plate 2 and the steel plate 7. The external force is removed, and prestress is established in the FRP plate 3 6, the steel plate 7 and the corrugated tooth plate 1, the corrugated tooth plate 2, and the double corrugated tooth FRP-steel prestressed connection node is completed.

[0047] It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention, and these improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A double corrugated tooth FRP plate prestressed connection node, characterized in that: It includes a first FRP plate and a second FRP plate to be connected; The connecting ends of the FRP plate 1 and the FRP plate 2 are provided with two full-length corrugated tooth plates, the corrugated tooth plates including corrugated tooth plate 1 and corrugated tooth plate 2, which are respectively located on the upper and lower surfaces of the FRP plate 1 and the FRP plate 2; The contact between the corrugated tooth plate and the FRP plate 1 and the FRP plate 2 is provided with corrugated teeth, the shape, size and number of the corrugated teeth of the corrugated tooth plate 1 and the corrugated tooth plate 2 are the same, and can form a bite, and the corrugated tooth plate 1 and the corrugated tooth plate 2 are provided with a plurality of internal threaded holes on both sides along the length direction, and the size, hole spacing and vertical distance to the edge of the corrugated tooth plate of each internal threaded hole are the same; The corrugated tooth plate 1 and the corrugated tooth plate 2 are pre-stress plates. Under the action of pressure, the corrugated tooth plate 1 and the corrugated tooth plate 2 cause the FRP plate 1 and the FRP plate 2 to deform. The deformed FRP plate 1 and the FRP plate 2 fit tightly with the two corrugated tooth plates. Keeping the pre-stress unchanged, a fastening system is installed on the corrugated tooth plate 1 and the corrugated tooth plate 2. The fastening system consists of a plurality of steel bars and high-strength bolts. Two bolt holes are provided on each of the steel bars, and they correspond one to one with the internal threaded holes on the two side surfaces of the two corrugated tooth plates along the length direction. The angle between any two adjacent steel bars is 45°. After the external force is removed, prestress is established in the FRP plate 1, the FRP plate 2 and the two corrugated tooth plates to form a prestressed connection node of a double corrugated tooth FRP plate.

2. A double corrugated tooth FRP plate prestressed connection node according to claim 1, characterized in that: The number of steel bars of the fastening system on both sides of the corrugated tooth plate 1 and the corrugated tooth plate 2 is not less than 19.

3. A double corrugated tooth FRP plate prestressed connection node according to claim 1, characterized in that: The diameter of the bolt hole on the steel bar is 0.03 mm larger than the diameter of the high-strength bolt.

4. A double corrugated tooth FRP plate prestressed connection node according to claim 1, characterized in that: Chamfers are arranged at the positions where the two corrugated tooth plates are in contact with the first FRP plate and the second FRP plate along the plate edges in the width direction.

5. A double corrugated tooth FRP plate prestressed connection node according to claim 1, characterized in that: The material of the corrugated tooth plate is steel or aluminum alloy.

6. A construction method for a double-corrugated FRP plate prestressed connection node according to claim 1, 2, 3, 4 or 5, characterized in that: The steps include: 1) Place the corrugated tooth plate 1 and the corrugated tooth plate 2 on the upper and lower surfaces of the FRP plate 1 and the FRP plate 2 respectively, with the corrugated tooth surfaces of the two corrugated tooth plates facing the FRP plate 1 and the FRP plate 2; 2) Apply uniform pressure, and when the straight section of the corrugated tooth plate with corrugated tooth surface is tightly fitted with FRP plate 1 and FRP plate 2, stop applying pressure and keep the pressure constant; 3) Install the fastening system, which is composed of a number of steel bars and high-strength bolts, and embed the high-strength bolts in the fastening system into a number of corresponding internal threaded holes provided on both sides of the corrugated tooth plate 1 and the corrugated tooth plate 2 along the length direction; 4) The external force is removed, and prestress is established in the FRP plate 1, the FRP plate 2 and the two corrugated tooth plates to form a prestressed connection node of the double corrugated tooth FRP plates.

Images