CN110725193A - Full-prefabricated steel pipe concrete space truss-UHPC waffle slab composite beam and construction method - Google Patents

Abstract

The invention discloses a fully prefabricated concrete-filled steel tube space truss-UHPC waffle plate composite beam and a construction method. The composite beam mainly includes three parts: a concrete-filled steel tube space truss, a prefabricated UHPC waffle bridge deck, and a shear trough connector. The construction method includes the following steps: (1) processing, manufacturing and assembling the concrete-filled steel tubular space truss; (2) prefabricating and transporting the UHPC waffle bridge deck; (3) pouring shear grooves and wet joints. Among them, the concrete-filled steel tubular space truss and the prefabricated waffle bridge deck are fixed together by shear groove connectors. The composite beam of the invention has reasonable stress, high strength, high rigidity and small height, fully meets the clearance requirements, light weight, convenient transportation, hoisting and splicing, good seismic performance and fatigue resistance, and has good economic benefits and practical value.

Description

Fully prefabricated concrete-filled steel tubular space truss-UHPC waffle slab composite beam and construction method

technical field

The invention relates to the technical field of bridge engineering, in particular to a fully prefabricated concrete-filled steel tube space truss-UHPC waffle plate composite beam and a construction method.

Background technique

Accelerated Bridge Construction (ABC) originated in the United States, mainly through the factory prefabrication of components, the use of special transportation equipment to transport components to the site and installation, to achieve a technology to speed up the construction of bridges on site. The steel-concrete composite beam has excellent mechanical properties of the upper concrete slab under compression and the lower steel girder under tension, and it is easy to assemble the steel girder and the precast concrete slab. It was first considered by engineers and applied in the rapid construction of bridges. However, because the traditional concrete slab is thick and has a large self-weight, it is not easy to meet the hoisting requirements, and the concrete in the negative bending area is prone to cracking under tension, resulting in poor durability of the composite beam.

Therefore, it is proposed to replace traditional concrete slabs with ultra-high performance concrete (UHPC) slabs, which have excellent mechanical properties and good durability, and have a lighter self-weight. Due to the higher material strength of UHPC, a smaller plate thickness can meet the force requirements, but the insufficient thickness of the plate leads to insufficient rigidity, and then a waffle plate structure with longitudinal and transverse ribs is proposed. The traditional I-beam-concrete composite beam has a single form, limited span, and poor torsional performance.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a fully prefabricated concrete-filled steel tubular space truss-UHPC waffle plate composite beam and a construction method, the composite beam has reasonable stress, high strength, high rigidity, small height, fully meets the clearance requirements, and has a relatively high self-weight. Light, easy to transport, hoist and splicing, good seismic performance and fatigue resistance.

In order to achieve the above purpose, a technical solution of the present invention is: a fully prefabricated concrete-filled steel tubular space truss-UHPC waffle plate composite beam, comprising a prefabricated concrete-filled steel tubular space truss, and the concrete-filled steel tubular space truss is connected by flange bolts and prefabricated nodes. A prefabricated UHPC waffle bridge deck is placed above the CFST space truss, and the prefabricated UHPC waffle bridge deck and the CFST space truss are connected to each other through shear groove connectors.

Further, the cross-section of the concrete-filled steel tube space truss is a single row with a single row, a single row with multiple rows, a single row with multiple racks, or multiple rows with multiple racks.

Further, the cross-sectional shape of the concrete-filled steel tube space truss is a triangle with three limbs, a rectangle with four limbs, or a trapezoid with five limbs.

Further, the concrete-filled steel tubular space truss is composed of upper chord, web and lower chord, and is divided into standard beam segment, negative bending moment segment and node segment, wherein the standard beam segment is only filled with concrete on the lower chord, and the negative bending The upper and lower chords of the moment segment are filled with concrete.

Further, the steel pipes in the concrete-filled steel tubular space trusses are round steel pipes, rectangular steel pipes, and trapezoidal steel pipes.

Further, the CFST space truss is provided with a stiffening structure composed of studs or perforated steel plates.

Further, the shear groove connector is a tenon connector or a group nail shear connector.

Further, the cross-section of the prefabricated UHPC waffle bridge deck is rectangular, trapezoidal or U-shaped.

In order to achieve the above purpose, another technical scheme of the present invention is: a construction method of a fully prefabricated concrete-filled steel tubular space truss-UHPC waffle plate composite beam, comprising the following steps:

(1) Processing, manufacturing and installation of concrete-filled steel tubular space truss: Divide the processed steel pipe into upper chord, web and lower chord, respectively carry out the steps of whether to pour concrete, and assemble the upper chord, web and lower chord into a standard Beam segments, negative bending moment segments, and node segments are pre-tightened by flange bolts and prefabricated nodes, assembled into an overall space truss or part of a space truss, and the shear trough connectors are positioned and welded to the concrete filled steel tube. on the space truss, and then transported to the site;

(2) Prefabricated and transported UHPC waffle bridge deck: According to the width and span of the bridge deck, the bridge deck is divided into several bridge deck units, and UHPC of different sizes, with shear grooves and toothed joints are poured in the designated formwork system For the waffle bridge deck, after 72 hours of room temperature curing, the mold is removed for 72 hours of steam curing, and the maintenance is completed and transported to the site;

(3) Pouring shear grooves and wet joints: Final tightening of the flange bolts of the steel tube space truss, respectively hoisting the concrete filled steel tube space truss and the bridge deck to the designated position, pouring the shear groove, so that the truss and the bridge deck are connected through compared with the prior art, the beneficial effects brought by the technical scheme of the present invention are:

1. A novel fully prefabricated concrete-filled steel tubular space truss-UHPC waffle plate composite beam of the present invention is composed of standard beam segments, negative bending moment segments and node segments, and each segment is connected by flanges and bolts, It can achieve complete prefabrication and assembly, which is convenient for assembly and rapid construction. And compared with the traditional I-beam-concrete composite beam, it has the advantages of reasonable stress, high bearing capacity, high flexural rigidity, good stability and integrity, good seismic performance and fatigue resistance. Simple, low cost, small height, fully meet the clearance requirements.

2. A concrete-filled steel tube space truss-UHPC waffle plate composite beam construction method of the present invention, the UHPC waffle plate and the steel tube concrete space truss are fully combined by pouring shear grooves, and each UHPC waffle plate is fully combined by pouring vertical and horizontal wet joints. The board is connected as a whole. It can realize batch prefabrication, efficient and convenient construction, convenient for transportation, hoisting and splicing, environmental protection and safety, and can ensure the construction accuracy of composite beams, and has good economic benefits and practical value.

Description of drawings

Fig. 1 is the structural representation of the composite beam of the present invention;

Fig. 2 is the structural representation of the concrete-filled steel tubular space truss of the present invention;

Fig. 3-1 and Fig. 3-2 are detailed structural schematic diagrams of concrete-filled steel tubular space truss nodes of the present invention;

4 is a schematic cross-sectional view of a standard beam segment and a negative bending moment segment of a bridge pier of the composite beam of the present invention.

Figures 5-1 to 5-4 are four schematic cross-sectional views of the concrete-filled steel tubular space truss of the present invention.

Figures 6-1 to 6-8 are schematic cross-sectional views of eight steel pipes of the present invention.

FIG. 7 is a schematic flow chart of the construction method of the composite beam of the present invention.

Marked in the figure: 1- Upper chord, 2- Web, 3- Lower chord, 4- Concrete-filled steel tube space truss, 5- Shear groove connection, 6- UHPC waffle bridge deck, 7- Flange, 8- Bolt , 9- prefabricated joint, 10- stud, 11- perforated steel plate, 12- standard beam segment, 13- negative moment segment, 14- node segment.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention is further described below with reference to the accompanying drawings.

As shown in Figures 1 to 3-2, a fully prefabricated CFST space truss-UHPC waffle plate composite beam includes a prefabricated CFST space truss 4, and the CFST space truss 4 passes through flanges 7, bolts 8 and prefabricated nodes 9. For splicing, a prefabricated UHPC waffle bridge deck 6 is placed on the CFST space truss 4 , and the prefabricated UHPC waffle bridge deck 6 is connected with the CFST space truss 4 through shear groove connectors 5 .

In the embodiment of the present invention, as shown in Figures 1 and 2, the cross-sectional shape of the concrete-filled steel tubular space truss 4 can be three limbs (triangle, of course, four limbs (rectangle) or five limbs (trapezoid).

In the embodiment of the present invention, as shown in FIGS. 3-1 to 4 , the concrete-filled steel tubular space truss 4 is composed of upper chord 1, web 2, lower chord 3 and other rod systems, and is divided into standard beam segments 12, pier negative Moment segment 13, node segment 14 and other segments, of which the standard beam segment 12 is only filled with concrete on the lower chord, and the upper and lower chords of the pier negative moment segment 13 are filled with concrete. The upper chord 1, the web 2 and the lower chord 3 are all made of steel pipes.

In the embodiment of the present invention, as shown in Fig. 5-1 to Fig. 5-4, the cross section of the concrete-filled steel tubular space truss 4 can be multi-single row, of course, it can also be single-single-row, single-single multi-row, multi-row Multiple rows.

In the embodiment of the present invention, as shown in Figs. 6-1 to 6-3, the steel pipe is a round steel pipe, of course, it can also be a rectangular steel pipe or a trapezoidal steel.

In the embodiment of the present invention, as shown in FIGS. 6-1 to 6-6 , the concrete filled steel tube is a solid concrete filled steel tube, and it may also be a hollow concrete filled steel tube.

In the embodiment of the present invention, as shown in FIGS. 6-7 and 6-8 , the CFST internal stiffening structure is a stud 10 , and of course it can also be a perforated steel plate 11 .

In the embodiment of the present invention, as shown in FIGS. 1 and 2 , the shear groove connector is a tenon connector, and of course it can also be a group nail connector.

In the embodiment of the present invention, as shown in FIGS. 1 and 4 , the cross-section of the prefabricated UHPC waffle bridge deck 6 is rectangular, and of course it can also be trapezoidal or U-shaped.

As shown in Figure 7, a construction method of a fully prefabricated concrete-filled steel tubular space truss-UHPC waffle plate composite beam includes the following steps:

(1) Processing, manufacturing and installation of concrete-filled steel tubular space truss: Divide the processed steel pipe into upper chord, web and lower chord, respectively carry out the steps of whether to pour concrete, and assemble the upper chord, web and lower chord into a standard Beam segments, pier negative moment segments, and node segments are pre-tightened by flange bolts and prefabricated nodes, assembled into an overall space truss or part of a space truss, and the shear groove connectors are positioned and welded to the steel pipe. on concrete space trusses and then transported to the site;

(2) Prefabricated and transported UHPC waffle bridge deck: According to the width and span of the bridge deck, the bridge deck is divided into several bridge deck units, and UHPC of different sizes, with shear grooves and toothed joints are poured in the designated formwork system For the waffle bridge deck, after 72 hours of room temperature curing, the mold is removed for 72 hours of steam curing, and the maintenance is completed and transported to the site;

(3) Pouring shear grooves and wet joints: Final tightening of the flange bolts of the steel tube space truss, respectively hoisting the concrete filled steel tube space truss and the bridge deck to the designated position, pouring the shear groove, so that the truss and the bridge deck are connected through The parts are connected, and the vertical and horizontal wet joints are poured, so that the different bridge deck units are connected as a whole. The basic principles and main features of the present invention and the advantages of the present invention have been shown and described above. Those skilled in the art should understand that the present invention is not limited by the above-mentioned embodiments, and the descriptions in the above-mentioned embodiments and the description are only to illustrate the principle of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have Various changes and modifications fall within the scope of the claimed invention. The claimed scope of the present invention is defined by the appended claims and their equivalents.

Claims (9)

1. A fully prefabricated CFST space truss-UHPC waffle plate composite beam, comprising a prefab CFST space truss, the CFST space truss is formed by splicing flange bolts and prefabricated nodes, and the CFST space truss is placed above the CFST space truss There are prefabricated UHPC waffle bridge decks, and the prefabricated UHPC waffle bridge decks and the concrete-filled steel tubular space trusses are connected to each other through shear groove connectors. 2. The fully prefabricated concrete-filled steel tubular space truss-UHPC waffle plate composite beam according to claim 1, wherein the cross-section of the concrete filled steel tubular space truss is a single row, a single row, a single row, and a single row. Or more and more rows. 3 . The fully prefabricated CFST space truss-UHPC waffle plate composite beam according to claim 1 , wherein the cross-sectional shape of the CFST space truss is a triangle with three limbs, a rectangle with four limbs, or a trapezoid with five limbs. 4 . 4. The fully prefabricated CFST space truss-UHPC waffle plate composite beam according to claim 1, wherein the CFST space truss is composed of an upper chord, a web member, and a lower chord, and is divided into standard beam segments , Negative moment segment and node segment, in which the standard beam segment is only filled with concrete on the lower chord, and the upper and lower chords of the negative moment segment are filled with concrete. 5 . The fully prefabricated CFST space truss-UHPC waffle plate composite beam according to claim 1 , wherein the steel pipes in the CFST space truss are round steel pipes, rectangular steel pipes, and trapezoidal steel pipes. 6 . 6 . The fully prefabricated CFST space truss-UHPC waffle plate composite beam according to claim 1 , wherein the CFST space truss is provided with a stiffening structure composed of studs or perforated steel plates. 7 . 7 . The fully prefabricated concrete-filled steel tubular space truss-UHPC waffle plate composite beam according to claim 1 , wherein the shear groove connector is a tenon connector or a group nail shear connector. 8 . 8 . The fully prefabricated CFST space truss-UHPC waffle slab composite beam according to claim 1 , wherein the prefabricated UHPC waffle slab has a rectangular, trapezoidal or U-shaped section. 9 . 9. the construction method of full prefabricated concrete-filled steel tubular space truss-UHPC waffle plate composite beam according to claim 1, comprising the following steps: (1) Processing, manufacturing and installation of concrete-filled steel tube space truss: Divide the processed steel tubes into upper chord, web and lower chord, and assemble the upper chord, web and lower chord into a standard according to the requirements of whether to pour concrete or not. Beam segments, pier negative moment segments and node segments are pre-tightened by flange bolts and prefabricated nodes, assembled into an overall space truss or part of a space truss, and the shear trough connectors are positioned and welded to the steel pipe. on concrete space trusses and then transported to the site; (2) Prefabricated and transported UHPC waffle bridge deck: According to the width and span of the bridge deck, the bridge deck is divided into several bridge deck units, and UHPC of different sizes, with shear grooves and toothed joints are poured in the designated formwork system For the waffle bridge deck, after 72 hours of room temperature curing, the mold is removed for 72 hours of steam curing, and the maintenance is completed and transported to the site; (3) Pouring shear grooves and wet joints: Final tightening of the flange bolts of the CFST space truss, respectively hoisting the CFST space truss and the UHPC waffle deck to the designated positions, and pouring the shear grooves so that the trusses and The bridge decks are connected through shear groove connectors, and longitudinal and horizontal wet joints are poured to connect different UHPC waffle deck units as a whole.

Images