FRP circular truss web member semi-open joint and manufacturing method

Abstract

The invention belongs to the technical field of bridge engineering, and discloses an FRP circular truss web member semi-open node and a manufacturing method.The FRP circular truss web member semi-open node comprises two oppositely-inclined FRP truss web members and an FRP connecting sleeve, the FRP connecting sleeve comprises an annular columnar section and a plane section, an opening is formed in one side of the annular columnar section of the FRP connecting sleeve, two parallel right-angled trapezoidal plates are arranged at the opening, and the two right-angled trapezoidal plates are arranged on the plane section of the FRP connecting sleeve; the two right trapezoid plates are arranged in the FRP connecting sleeve, the bevel edges of the two right trapezoid plates are fixedly connected with the annular columnar section of the FRP connecting sleeve, the short edge of the two parallel edges of each right trapezoid plate faces upwards, the long edge of the two parallel edges of each right trapezoid plate faces downwards, the right trapezoid plates are plane sections of the FRP connecting sleeve, and the right-angle waist portions of the right trapezoid plates of the two FRP connecting sleeves are tightly attached to each other. An FRP connecting plate is arranged at the attached position of the two FRP connecting sleeves, and the FRP connecting sleeves and the FRP truss web members are filled with concrete. According to the joint, the two FRP arc-shaped connecting sleeves are connected through the two plates, the connecting strength is improved, and the strength and stability of the whole joint are improved.

Description

Technical Field

[0001] The invention relates to the technical field of bridge engineering, and in particular to a semi-open node of an FRP circular truss web member and a manufacturing method thereof. Background Art

[0002] Composite truss belly bridges have the advantages of simple design and installation, wide applicable span range, fast construction speed, etc., and are widely used. As an important part of the bridge, the structure and performance of the composite truss belly bridge connection node will have a direct impact on the overall force of the bridge. At present, most composite truss belly bridges adopt steel trusses. Traditional steel trusses are heavy and easy to rust, which will not only have adverse effects on the stability, safety and durability of the bridge structure, but also have very high maintenance costs in the later stage. Therefore, a material with low quality, corrosion resistance and low maintenance cost is needed to solve these problems. FRP materials have the advantages of light weight, high strength, good durability and high wear resistance. Replacing steel trusses and nodes with FRP materials can give full play to the excellent performance of FRP materials and eliminate the unfavorable factors such as easy corrosion, difficult maintenance and heavy weight of steel trusses. However, the special properties of FRP materials make it impossible to be processed into various shapes like steel, and it cannot be welded, so the production of FRP nodes is more difficult. Summary of the invention

[0003] In order to solve the problems of heavy weight, easy corrosion and high maintenance cost of steel structure bridges in the above-mentioned prior art, the present invention provides a semi-open node of FRP circular truss web and a manufacturing method, which can effectively connect the FRP circular truss web, reduce the weight of the bridge truss, prevent corrosion, reduce maintenance costs, and improve the durability and wear resistance of the bridge structure.

[0004] The present invention is realized through the following technical scheme: it comprises two FRP truss web members inclined toward each other and an FRP connecting sleeve sleeved on the FRP truss web members and fixedly connected thereto, the FRP connecting sleeve comprises an annular columnar section and a plane section, one side of the annular columnar section of the FRP connecting sleeve is open, two parallel right-angled trapezoidal plates are arranged at the opening, and the oblique sides of the two right-angled trapezoidal plates are fixedly connected to the annular columnar section of the FRP connecting sleeve, the shorter side of the two parallel sides of the right-angled trapezoidal plate faces upward, and the longer side faces downward, the right-angled trapezoidal plate is the plane section of the FRP connecting sleeve, the right-angled waist parts of the right-angled trapezoidal plates of the two FRP connecting sleeves are tightly fitted, an FRP connecting plate is arranged at the fitting position of the two FRP connecting sleeves, the FRP connecting plate and the FRP connecting sleeve are fixedly connected, and concrete is poured between the right-angled trapezoidal plates of the two FRP connecting sleeves and in the FRP truss web member.

[0005] As a further preference, the FRP truss web member is in the shape of an annular column as a whole.

[0006] As a further preference, a plurality of groups of bolt holes are arranged on the annular columnar section of the FRP connecting sleeve and the FRP truss web along the circumferential direction of the FRP truss web, each group of bolt holes is arranged in an axial array along the FRP truss web, and the FRP connecting sleeve and the FRP truss web are fixedly connected by second high-strength bolts and nuts.

[0007] As a further preference, the right-angled trapezoidal plate of the FRP connecting sleeve is provided with a plurality of bolt holes arranged in an array, the FRP connecting plate is provided with a plurality of bolt holes, and the FRP connecting sleeve and the FRP connecting plate are fixedly connected by first high-strength bolts and nuts.

[0008] As a further preferred embodiment, a plurality of FRP reinforcement frames arranged in a circumferential array are arranged in the FRP truss web, a plurality of FRP stirrups are sleeved on the outside of the FRP reinforcement frames, and prestressed steel bars are arranged at the axis of the FRP truss web.

[0009] As a further preference, the spacing between each group of bolt holes on the annular columnar section of the FRP connecting sleeve and the FRP truss web is in the range of 10-20 cm, and the distance between the two right-angled trapezoidal plates of the FRP connecting sleeve is not less than 15 cm.

[0010] As a further preference, the angle between the center lines of the two groups of bolt holes near the opening of the annular columnar section of the FRP connecting sleeve is 135 degrees, and the remaining groups of bolt holes of the annular columnar section of the FRP connecting sleeve are evenly distributed along the circumferential direction of the FRP truss web.

[0011] The present invention also provides a method for manufacturing the semi-open node of the FRP circular truss web member of the present invention, comprising the following steps:

[0012] S1. Insert two FRP truss webs into two FRP connecting sleeves respectively, keep the upper ends flush, make the FRP connecting sleeves completely wrap around the FRP truss webs, align the bolt holes of the annular columnar section of the FRP connecting sleeves with the bolt holes on the FRP truss webs, and fix the connection with the second high-strength bolts and nuts;

[0013] S2, aligning the right-angle waist parts of the right-angle trapezoidal plates of the two FRP connecting sleeves, and then aligning the FRP connecting plates with the upper and lower bottom edges of the right-angle trapezoidal plates of the FRP connecting sleeves respectively, and at the same time, aligning the bolt holes on the FRP connecting plates with the bolt holes on the plane section of the FRP connecting sleeves, and fixing the connection with the first high-strength bolts and nuts;

[0014] S3. Add FRP reinforcement frame to the FRP truss web, set FRP stirrups on the outside of the FRP reinforcement frame, add a prestressed steel bar at the longitudinal axis of the FRP truss web, and then pour concrete.

[0015] As a further preferred embodiment, before step S1, the outer surface of the FRP web member and the inner surface of the FRP connecting sleeve are respectively roughened.

[0016] As a further preferred embodiment, before step S2, the FRP connecting plate and the FRP connecting sleeve are respectively roughened on one side where they are bonded to each other.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. All components of the node of the present invention can be prefabricated, which saves time and improves work efficiency. The components are connected by high-strength bolts, which makes construction convenient.

[0019] 2. In the node of the present invention, two FRP arc-shaped connecting sleeves are connected by two plates, which improves the connection strength and enhances the strength and stability of the entire node.

[0020] 3. The present invention adopts FRP semi-open nodes, leaving a certain amount of opening and closing margin when installing the FRP circular truss web members, which can make the installation of the FRP circular truss web members more convenient and the positioning more accurate.

[0021] 4. Compared with traditional steel structure components, the nodes of the present invention have light weight, good durability, high wear resistance, lower subsequent maintenance costs, and better economy. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the overall structure of the node of the present invention.

[0023] Figure 2 for Figure 1 Top view of the .

[0024] Figure 3 for Figure 2 AA section view.

[0025] Figure 4 This is a partially enlarged schematic diagram of the FRP arc-shaped connecting sleeve.

[0026] Figure 5 This is a partial enlarged schematic diagram of the FRP tendon and prestressed steel bar structure.

[0027] Indicated in the figure:

[0028] 1. FRP connecting sleeve; 2. FRP truss web; 3. FRP connecting plate; 4. First high-strength bolt; 5. Second high-strength bolt; 6. Nut; 7. FRP reinforcement frame; 8. Prestressed steel bar; 9. FRP stirrups; 10. Concrete. DETAILED DESCRIPTION

[0029] Advantages and features of the present invention will be illustrated and explained by the following non-limiting description of preferred embodiments thereof, which are given by way of example only with reference to the accompanying drawings.

[0030] like Figure 1 As shown, the present invention provides a semi-open node of FRP circular truss web, comprising two FRP truss webs 2 inclined toward each other, and a FRP connecting sleeve 1 is sleeved at the position close to the two FRP truss webs 2, and the FRP connecting sleeve 1 is fixedly connected to the FRP truss web 2. The FRP truss web 2 is in the shape of an annular column as a whole. Figure 4 As shown, the FRP connecting sleeve 1 includes an annular columnar section and a plane section. One side of the annular columnar section of the FRP connecting sleeve 1 is open, and two right-angled trapezoidal plates are arranged at the opening. The right-angled trapezoidal plates are the plane sections of the FRP connecting sleeve 1. The two right-angled trapezoidal plates are arranged in parallel, and the hypotenuses of the two right-angled trapezoidal plates are fixedly connected to the annular columnar section of the FRP connecting sleeve 1, preferably by welding. The shorter of the two parallel sides of the right-angled trapezoidal plate faces upward, and the longer side faces downward. The right-angled trapezoidal plate is provided with a plurality of bolt holes arranged in an array.

[0031] like Figure 1 and Figure 2 As shown, the right-angle waist parts of the right-angle trapezoidal plates of the two FRP connecting sleeves 1 fit tightly together, and an FRP connecting plate 3 is arranged at the fitting position of the two FRP connecting sleeves 1. The FRP connecting plate 3 is provided with a plurality of bolt holes, and the bolt holes on the FRP connecting plate 3 correspond one to one with the bolt holes on the right-angle trapezoidal plates of the FRP connecting sleeves 1. The first high-strength bolt 4 passes through the FRP connecting plate 3, the FRP connecting sleeve 1 and the FRP connecting plate 3 in sequence, and is connected by a nut 6. A plurality of bolt holes are arranged in an array on the circumferential surface of the annular columnar section of the FRP connecting sleeve 1 and the FRP truss web member 2, and the bolt holes on the annular columnar section of the FRP connecting sleeve 1 and the FRP truss web member 2 correspond one to one. The FRP connecting sleeve 1 and the FRP truss web member 2 are fixedly connected together by a second high-strength bolt 5 and a nut 6. The nut 6 is arranged on the outside of the FRP connecting sleeve 1.

[0032] like Figure 1 and Figure 3 As shown, the cavity between the two right-angle trapezoidal plates of the FRP connecting sleeves 1 and the cavity of the FRP truss web member 2 are filled with concrete 10 .

[0033] like Figure 1 , Figure 2 and Figure 4As shown, the annular columnar section and the plane section of the FRP connection sleeve 1 form a semi-open whole. Several groups of bolt holes are arranged on the annular columnar section of the FRP connection sleeve 1 along the circumferential direction of the FRP truss web member 2, and each group of bolt holes is arranged in an axial array along the FRP truss web member 2. The spacing between each group of bolt holes is between 10-20 cm, and the distance between the two right-angled trapezoidal plates of the FRP connection sleeve 1 is at least 15 cm. The angle between the center lines of the two groups of bolt holes near the opening of the annular columnar section of the FRP connection sleeve 1 is 135 degrees, and the remaining groups of bolt holes of the annular columnar section of the FRP connection sleeve 1 are evenly distributed along the circumferential direction of the FRP truss web member 2.

[0034] like Figure 1 , Figure 2 , Figure 3 and Figure 5 As shown, in order to increase the strength of the node, a plurality of FRP reinforcement skeletons 7 arranged in a circumferential array may be provided in the FRP truss web member 2, a plurality of FRP stirrups 9 are sleeved on the outside of the FRP reinforcement skeleton 7, and a prestressed steel bar 8 is provided at the axis of the FRP truss web member 2.

[0035] The present invention also provides a method for manufacturing the semi-open node of the FRP circular truss web member of the present invention, comprising the following steps:

[0036] S1: Connecting the FRP connecting sleeve 1 with the FRP truss web member 2, specifically, two FRP truss web members 2 are respectively extended into the FRP connecting sleeve 1, and the upper ends are kept flush, so that the FRP connecting sleeve 1 completely wraps the FRP truss web member 2, the bolt holes of the annular columnar section of the FRP connecting sleeve 1 are aligned with the bolt holes on the FRP truss web member 2, and connected with the second high-strength bolts 5, and the nut 6 is installed on the outside of the FRP connecting sleeve 1;

[0037] S2: Align the right-angle waist parts of the right-angle trapezoidal plates of the two FRP connecting sleeves 1, and then align the FRP connecting plate 3 with the upper and lower bottom edges of the right-angle trapezoidal plates of the FRP connecting sleeve 1, respectively, so that the FRP connecting plate 3 is close to the plane section of the FRP connecting sleeve 1, and align the bolt holes on the FRP connecting plate 3 with the bolt holes on the plane section of the FRP connecting sleeve 1, and connect them with the first high-strength bolts 4, and install the nuts 6 on the outside of the FRP connecting plate 3, and the distance between the bolt holes is between 10-20 cm;

[0038] S3: Add the FRP reinforcement skeleton 7 to the two FRP truss web members 2, sleeve the FRP stirrups 9 on the outside of the FRP reinforcement skeleton 7, and add one prestressed steel bar 8 at the longitudinal axis position of the two FRP truss web members 2, and then pour the concrete 10 to ensure that the gap between the FRP connecting sleeve 1 and the FRP truss web member 2 is filled with concrete 10, and the entire FRP connection node is completely wrapped by the concrete 10.

[0039] The above steps also include: in the step S1, before the FRP truss web member 2 extends into the FRP connecting sleeve 1, the outer surface of the FRP truss web member 2 and the inner side of the FRP connecting sleeve 1 are respectively roughened, so that the FRP connecting sleeve 1 completely wraps the FRP truss web member 2 and is connected with the second high-strength bolt 5; in the step S2, before the FRP connecting plate 3 is tightly attached to the plane section of the FRP connecting sleeve 1, the side where the FRP connecting plate 3 and the FRP connecting sleeve 1 are respectively roughened, that is, the inner side of the FRP connecting plate 3 and the outer side of the plane section of the FRP connecting sleeve 1 are roughened, and then connected with the first high-strength bolt 4.

[0040] In addition to the above embodiments, the present invention may also have other implementation modes. Any technical solutions formed by equivalent replacement or equivalent transformation shall fall within the protection scope required by the present invention.

Claims

1. A semi-open node of FRP circular truss web, characterized by: The invention comprises two FRP truss web members (2) arranged obliquely towards each other and an FRP connecting sleeve (1) sleeved on the FRP truss web members (2) and fixedly connected thereto, wherein the FRP connecting sleeve (1) comprises an annular columnar section and a planar section, wherein one side of the annular columnar section of the FRP connecting sleeve (1) is open, and two parallel right-angled trapezoidal plates are arranged at the opening, and the oblique sides of the two right-angled trapezoidal plates are fixedly connected to the annular columnar section of the FRP connecting sleeve (1), and the shorter of the two parallel sides of the right-angled trapezoidal plate is One side faces upwards and the longer side faces downwards; the right-angled trapezoidal plate is a plane section of the FRP connecting sleeve (1); the right-angled waist parts of the right-angled trapezoidal plates of the two FRP connecting sleeves (1) are tightly fitted; an FRP connecting plate (3) is arranged at the fitting position of the two FRP connecting sleeves (1); the FRP connecting plate (3) and the FRP connecting sleeve (1) are fixedly connected; concrete (10) is poured between the right-angled trapezoidal plates of the two FRP connecting sleeves (1) and in the FRP truss web member (2).

2. The FRP circular truss web member semi-open node according to claim 1, characterized in that: The FRP truss web member (2) is in the shape of an annular column as a whole.

3. The FRP circular truss web member semi-open node according to claim 2, characterized in that: A plurality of groups of bolt holes are arranged on the annular columnar section of the FRP connecting sleeve (1) and the FRP truss web member (2) along the circumferential direction of the FRP truss web member (2), and each group of bolt holes is arranged in an axial array along the FRP truss web member (2). The FRP connecting sleeve (1) and the FRP truss web member (2) are fixedly connected by a second high-strength bolt (5) and a nut (6).

4. The FRP circular truss web member semi-open node according to claim 3, characterized in that: The right-angled trapezoidal plate of the FRP connecting sleeve (1) is provided with a plurality of bolt holes arranged in an array, the FRP connecting plate (3) is provided with a plurality of bolt holes, and the FRP connecting sleeve (1) and the FRP connecting plate (3) are fixedly connected by means of a first high-strength bolt (4) and a nut (6).

5. The FRP circular truss web member semi-open node according to claim 4, characterized in that: A plurality of FRP reinforcement frames (7) arranged in a circumferential array are arranged inside the FRP truss web member (2), a plurality of FRP stirrups (9) are sleeved on the outside of the FRP reinforcement frame (7), and a prestressed steel bar (8) is arranged at the axis of the FRP truss web member (2).

6. The FRP circular truss web member semi-open node according to claim 5, characterized in that: The spacing between each group of bolt holes on the annular columnar section of the FRP connecting sleeve (1) and the FRP truss web member (2) is in the range of 10-20 cm, and the distance between the two right-angled trapezoidal plates of the FRP connecting sleeve (1) is not less than 15 cm.

7. The FRP circular truss web member semi-open node according to claim 6, characterized in that: The angle between the center lines of the two groups of bolt holes near the opening of the annular columnar section of the FRP connecting sleeve (1) is 135 degrees, and the remaining groups of bolt holes of the annular columnar section of the FRP connecting sleeve (1) are evenly distributed along the circumferential direction of the FRP truss web member (2).

8. A method for manufacturing a semi-open node of an FRP circular truss web member applicable to any one of claims 5 to 7, characterized in that: The following steps are included: S1. Insert two FRP truss web members (2) into two FRP connecting sleeves (1) respectively, keep the upper ends flush, make the FRP connecting sleeves (1) completely wrap around the FRP truss web members (2), align the bolt holes of the annular columnar section of the FRP connecting sleeves (1) with the bolt holes on the FRP truss web members (2), and fix them with the second high-strength bolts (5) and nuts (6); S2, aligning the right-angle waist parts of the right-angle trapezoidal plates of the two FRP connecting sleeves (1), and then aligning the FRP connecting plates (3) with the upper and lower bottom edges of the right-angle trapezoidal plates of the FRP connecting sleeves (1), and at the same time, aligning the bolt holes on the FRP connecting plates (3) with the bolt holes on the plane section of the FRP connecting sleeves (1), and fixing the connection with the first high-strength bolts (4) and nuts (6); S3, adding an FRP reinforcement frame (7) to the FRP truss web member (2), sleeved with FRP stirrups (9) on the outside of the FRP reinforcement frame (7), adding a prestressed steel bar (8) at the longitudinal axis position of the FRP truss web member (2), and then pouring concrete (10).

9. The method for manufacturing a semi-open node of a FRP circular truss web member according to claim 8, characterized in that: Prior to step S1, the outer surface of the FRP web member (2) and the inner surface of the FRP connecting sleeve (1) are respectively roughened.

10. The method for manufacturing a semi-open node of a FRP circular truss web member according to claim 8, characterized in that: Prior to step S2, one side of the FRP connecting plate (3) and the FRP connecting sleeve (1) that are bonded to each other is roughened.

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