CN117248438A - Truss structure form-based assembled UHPC web plate flange arch structure and construction method thereof - Google Patents

Abstract

The present invention relates to an assembled UHPC web Meilan arch structure based on a truss structure and a construction method thereof. The assembled UHPC web Meilan arch structure based on a truss structure includes steel tube concrete chords, UHPC Butterfly web, cross-connected steel pipes and web-chord joints; the two parallel concrete-filled steel pipe chords at the upper part are connected vertically and vertically with a cross-connected steel pipe, and the two parallel concrete-filled steel pipe chords at the lower part are connected Horizontal steel pipes are vertically fixedly connected between the pipes. In the same facade, the upper concrete-filled steel pipe chords and the lower concrete-filled steel pipe chords are connected through UHPC butterfly webs. The concrete-filled steel pipe chords and The UHPC butterfly webs are connected through web and chord joints. The web and chord joints are formed by bolting the perforated steel plate welded on the steel tube concrete chord to the UHPC butterfly web; and Compared with the traditional Meilan arch structure form, this application has a novel structural structure, good mechanical properties, and relatively simple construction of an assembled UHPC web Meilan arch structure and its construction method.

Description

A kind of assembled UHPC web Meilan arch structure based on truss structure and its construction work method

Technical areas:

The invention relates to the technical field of bridges and is an assembled UHPC web Meilan arch structure based on a truss structure and a construction method thereof.

Background technique:

Arch bridge is an ancient architectural structure with the advantages of low maintenance cost and beautiful appearance. It is widely used in our country; currently, the world's largest stone arch bridge (Dan River Bridge, built in 2000, main span 146m), steel arch bridge ( Chongqing Chaotianmen Bridge, completed in 2009, main span 552), steel tube concrete arch bridge (Pingnan Third Bridge, completed in 2020, main span 575m) and Meilan Arch Bridge (Beipanjiang Super Bridge, completed in 2016, main span 445m) are all In China, the successful practice of these arch bridges has accumulated valuable experience for the construction of my country's extra-long-span arch bridges, and has made my country's arch bridge construction technology a leader in the world.

Compared with other bridge types, using Meilan arch bridge to cross valleys often saves 1/3 to 1/2 of the cost, and Meilan arch has the advantages of high load-bearing capacity, high stiffness, good durability, and low later maintenance workload. However, At present, the Meilan Arch structure still has problems such as excessive self-weight, frequent high-altitude construction operations, and long construction period, which restricts the application and development of the Meilan Arch.

In order to solve the above problems, some scholars have proposed using steel web bars (plates) to replace concrete webs. However, this method makes the cross-section stiffness of the arch ring low, and the steel components require long-term maintenance.

Contents of the invention:

The purpose of this invention is to provide an assembly with novel structural structure, good mechanical properties and relatively simple construction in order to solve the problems of large-span Meilan arch, which has a large number of web rods, a large self-weight of the arch ring and difficult web pouring. UHPC web Meilan arch structure and its construction method.

The present invention is based on the assembled UHPC web Meilan arch structure in the form of a truss structure, which is characterized by: including steel tube concrete chords, UHPC butterfly webs, transverse steel pipes and web and chord joints; two upper There are cross-connected steel pipes connected vertically and vertically between the parallel concrete-filled steel tube chords. There are cross-connected steel pipes vertically fixed between the two parallel steel-tube concrete chords located at the lower part. The upper steel pipes are located on the same facade. The concrete chord tube and the steel tube concrete chord tube located at the bottom are connected through a UHPC butterfly web, and the steel tube concrete chord tube and the UHPC butterfly web plate are connected through a web and chord joint. The web plate The joint with the chord is formed by bolting the perforated steel plate welded on the steel tube concrete chord to the UHPC butterfly web.

Further, the above-mentioned steel tube concrete chords, transverse steel pipes, webs and chord pipe joints are covered with concrete roof and bottom plates. The top and bottom plates are provided with top and bottom plate stirrups, top and bottom plate longitudinal bars and concrete. The top and bottom plates are The stirrups pass through the reserved steel holes in the UHPC butterfly web to improve the shear resistance of the interface between the UHPC butterfly web and the concrete roof and floor.

Further, the above-mentioned concrete-filled steel pipe chord is formed by solidifying concrete filled inside the steel pipe.

Further, the above-mentioned concrete steel tube chord is welded with two parallel spaced perforated steel plates. The distance between the two parallel spaced perforated steel plates is smaller than the diameter of the steel tube chord. The distance between the two parallel spaced perforated steel plates is smaller than the diameter of the steel tube chord. The UHPC butterfly web is inserted in between, and the bolts inserted into the holes on the perforated steel plate and the UHPC butterfly web are locked and fixed.

Furthermore, the above-mentioned UHPC butterfly web is a prefabricated plate, and multiple holes for installing high-strength bolts are reserved on the upper and lower edges of the UHPC butterfly web, as well as reserved steel holes in the web.

Furthermore, the width dimension of the middle parts of both sides of the above-mentioned UHPC butterfly web is smaller than the width dimension of the upper and lower parts. Arc transition sections are provided in the middle parts of both sides of the UHPC butterfly web. The sides of two adjacent UHPC butterfly webs form Fusiform cutout.

Furthermore, a temporary steel web rod is provided between the upper concrete-filled steel tube chord and the lower concrete-filled steel tube chord in the same facade. The temporary steel web rod and the UHPC butterfly web are in the concrete-filled steel tube chord 1 offset in the length direction.

The present invention is based on the construction method of the assembled UHPC web Meilan arch structure in the form of a truss structure. The steps are as follows:

(1) Set up the hoisting device according to the design size and requirements. While erecting the hoisting device, process the concrete-filled steel tube chords, temporary steel web bars and cross-connected steel pipes in the prefabrication plant, and install the cross-connected steel pipes and temporary steel pipes. The web rods and perforated steel plates are welded to the concrete-filled steel tube chords to form stiff skeleton segments;

(2) While processing the rigid frame segments, the UHPC butterfly webs are prefabricated in parallel. The above work should be completed before the hoisting work begins;

(3) After the hoisting device is set up, hoist the rigid frame segments and fix them to the designed position;

(4) After the rigid frame segments are installed, the UHPC butterfly web is hoisted and slid into the designed position between the upper and lower steel tube concrete chords through the reserved installation opening formed between the two perforated steel plates. , so that the bolt holes on the UHPC butterfly web are connected to the perforated steel plates on the concrete-filled steel tube chords, and then high-strength bolts are used to connect the two. Each UHPC butterfly web is arranged discontinuously and on the UHPC butterfly web, There is a gap between the lower edge and the concrete-filled steel tube chord;

(5) After one segment of UHPC butterfly web 2 is assembled, the next segment can be installed and repeat step ④;

(6) The instant closing device is used for closing. Before closing, the line shape and position of the main arch ring must be comprehensively reviewed and adjusted. During closing, operators must be arranged to close both ribs at the same time. After the arch ribs are closed to form a complete arch ring, the steel tube concrete is poured. Concrete inside the chord;

(7) When the strength of the concrete in the pipe reaches a certain level, remove the buckles and temporary steel web bars, tie the top and bottom plate stirrups and roof and bottom plate longitudinal bars, install the formwork, and finally pour the top and bottom plate concrete.

Compared with the traditional Meilan arch structural form, this structure has a novel structure, good mechanical properties, and relatively simple construction. It can better solve the problems of a large number of web rods and difficult web pouring in the long-span Meilan arch. The use of UHPC butterfly webs effectively reduces the weight of the arch ring and can also play a supporting role during the construction of the arch ring. On the premise of ensuring the load-bearing capacity of the Meilan Arch, a large number of steel web rods are reduced and the construction period is shortened. It improves the economy of the long-span Meilan arch bridge and has very broad application prospects.

Picture description:

Figure 1 is the overall layout of the Meilan arch bridge with assembled UHPC butterfly webs;

Figure 2 is a schematic assembly diagram of the UHPC butterfly web (i.e., the K view of Figure 1);

Figure 3 is a structural cross-sectional view of the assembled UHPC web Meilan arch (i.e., the A-A cross-section in Figure 2);

Figure 4 is a detailed enlarged view of the web and chord joint of the present invention.

In the picture: 1-Concrete steel tube chord, 2-UHPC butterfly web, 3-Transverse steel pipe, 4-Temporary steel web rod, 5-Concrete roof and bottom plate, 6-Web and chord joint, 7-With holes Steel plate, 8-high-strength bolts, 9-top and bottom plate stirrups, 10-top and bottom plate longitudinal bars, 11-reserved steel holes in the web.

Detailed ways:

In order to make the above-mentioned features and advantages of the present invention more obvious and easy to understand, embodiments are given below and described in detail with reference to the accompanying drawings.

UHPC butterfly webs are applied to the Meilan arch bridge. The overall layout is shown in Figure 1. An assembled UHPC web Meilan arch structure based on the truss structure and its construction method are shown in Figures 2~3. The Meilan arch structure of the assembled UHPC web includes a concrete-filled steel tube chord 1, a UHPC butterfly web 2, a cross-connected steel pipe 3, and a web-chord joint 6. The concrete-filled steel tube chord 1 is formed by solidifying the steel tube filled with concrete; The two parallel concrete-filled steel tube chords 1 located at the upper part are vertically and fixedly connected to each other with cross-connected steel pipes 3 , and the two parallel-disposed steel tube concrete chords 1 located at the lower part are connected to each other with horizontally connected steel pipes 3 at intervals. In the same facade, the concrete-filled steel tube chord 1 located at the upper part and the concrete-filled steel tube chord 1 located at the lower part are connected through UHPC butterfly web 2. The concrete-filled steel tube chord 1 and the UHPC butterfly web 2 are connected. The web and chord joints 6 are connected by the perforated steel plate 7 welded on the steel tube chord 1 and the UHPC butterfly web 2 through bolts 8 to form a joint.

The periphery of the concrete-filled steel tube chord 1, the transverse steel pipe 3 and the web-chord joint 6 is covered with a concrete roof and bottom plate 5. The concrete roof and bottom plate 5 is provided with top and bottom plate stirrups 9, top and bottom plate longitudinal bars 10 and concrete , the roof and bottom plate stirrups 9 pass through the reserved web steel holes 11 of the UHPC butterfly web 2 to improve the shear resistance of the interface between the UHPC butterfly web 2 and the concrete roof and bottom plate 5.

Two parallel-spaced perforated steel plates 7 are welded on the concrete-filled steel tube chord 1. The distance between the two parallel-spaced perforated steel plates 7 is smaller than the diameter of the concrete-filled steel tube chord 1. The two parallel-spaced perforated steel plates 7 are welded to the steel tube chord 1. A reserved installation opening is formed between them, and the reserved installation opening is inserted into the UHPC butterfly web 2. The holes on the perforated steel plate 7 are locked and fixed with the bolts 8 inserted into the UHPC butterfly web 2; The UHPC butterfly web 2 is a prefabricated plate, and multiple holes for installing high-strength bolts 8 are reserved on the upper and lower edges of the UHPC butterfly web 2, as well as reserved steel holes 11 in the web.

The width of the middle parts of both sides of the UHPC butterfly web 2 is smaller than the width of the upper and lower parts. Arc transition sections are provided in the middle of both sides of the UHPC butterfly web 2 (which is helpful in preventing stress concentration). The two adjacent UHPC butterflies A fusiform hollow is formed on the side of the shaped web 2; a temporary steel web bar 4 is provided between the upper concrete-filled steel tube chord 1 and the lower concrete-filled steel tube chord 1 in the same facade. The temporary steel web bar 4 It is offset from the UHPC butterfly web 2 in the length direction of the concrete-filled steel tube chord 1.

In the above embodiment, the size of the concrete-filled steel tube chord and the concrete strength are determined according to the actual engineering stress conditions. The UHPC strength and structural dimensions of the UHPC butterfly web 2 are determined according to the actual engineering stress conditions and the arch ring structure. The temporary steel The number and arrangement spacing of web bars 4 can be determined according to the construction requirements of the arch ring; the arrangement form of the top and bottom plate stirrups 9 determines the spacing of the reserved steel bar holes 11 in the web; the perforated steel plate on the UHPC butterfly web and chord joint 6 The size and hole spacing of 7 need to be determined according to the stress condition of the node, taking into account the web installation; the size and number of bolts 8 are determined according to the stress condition of the node.

The present invention is based on the construction method of the assembled UHPC web Meilan arch structure in the form of a truss structure. The steps are as follows:

(1) Set up the hoisting device according to the design size and requirements. While erecting the hoisting device, process the concrete-filled steel tube chord 1, temporary steel web rod 4 and cross-connected steel pipe 3 in the prefabrication plant, and install the cross-connected steel pipe. 3. Temporary steel web rods 4 and perforated steel plates 7 are welded to the concrete-filled steel tube chord 1 to form a stiff skeleton segment;

(2) While processing the rigid frame segments, prefabricate the UHPC butterfly web 2 in parallel. The above work should be completed before the hoisting work begins;

(3) After the hoisting device is set up, hoist the rigid frame segments and fix them to the designed position;

(4) After the installation of the rigid frame segments is completed, hoist the UHPC butterfly web 2 and slide it into the space between the upper and lower steel tube concrete chords 1 through the reserved installation opening formed between the two perforated steel plates 7 The design position is such that the bolt holes on the UHPC butterfly web 2 are docked with the perforated steel plate 7 on the concrete-filled steel tube chord 1, and then high-strength bolts 8 are used to connect the two. Each UHPC butterfly web 2 is arranged discontinuously. And there is a gap between the upper and lower edges of the UHPC butterfly web 2 and the concrete-filled steel tube chord 1;

(5) After one segment of UHPC butterfly web 2 is assembled, the next segment can be installed and repeat step ④;

(6) The instant closing device is used for closing. Before closing, the line shape and position of the main arch ring must be comprehensively reviewed and adjusted. During closing, operators must be arranged to close both ribs at the same time. After the arch ribs are closed to form a complete arch ring, the steel tube concrete is poured. Concrete inside the chord;

(7) When the strength of the concrete in the pipe reaches a certain level, remove the buckles and temporary steel web bars 4, tie the top and bottom plate stirrups 9 and top and bottom plate longitudinal bars 10 of the top and bottom plates 5 and install the formwork, and finally concrete the top and bottom plates 5 pouring work.

The above-mentioned hoisting device is an existing equipment, which includes buckle towers, anchors, buckle cables and hanging towers, etc. Its specific structure is briefly described as follows:

The buckle cable hoisting system is constructed using a diagonal-stay buckle cable hoisting system. The buckle-cable hoisting system consists of three parts: a lifting and installation cable crane, a diagonal-stay buckle system and a balance and stability system; the lifting and installation cable crane consists of the main load-bearing cable, It consists of main cable anchorage, hanging anchor, hoisting, traction, power machinery and other parts; the cable-stayed fastening system consists of the anchor point on the arch ring, the steel strand buckle cable, the front and rear balance cables of the buckle tower, the buckle anchor beam with the buckle cable tensioning end It is composed of other parts; the balance and stability system is composed of arch ring anchor points, steel wire rope wind cables, ground anchors and other parts; the buckle tower is assembled into a fully welded portal lattice column using universal rods, and the tower feet are consolidated; the buckle tower is erected on the top of the junction pier Cable anchor beams are also set up, and the segmental buckle cables and anchor cables are stretched to the ravine and both sides of the river respectively. The two are synchronized and balanced with the hoisting progress. During the tensioning process, the horizontal component of the anchor beam is always in a balanced state.

In step (5), the arch rib position (that is, the chord position of different segments) can be positioned using flange connections first, and then welded and fixed.

The present invention is based on the assembled UHPC web Meilan arch structure in the form of a truss structure and its construction method. The Meilan arch structure of the assembled UHPC web mainly consists of steel tube concrete chords, UHPC butterfly webs, horizontally connected steel pipes, It is composed of temporary steel web rods, outer concrete roof and bottom plates, and web and chord pipe joints. The web and chord pipe joints are formed by bolting the perforated steel plate welded on the chord pipe and the UHPC butterfly web; the concrete-filled steel tube The chord tube is composed of a steel pipe filled with concrete. Perforated steel plates need to be welded during the production of the steel pipe. The size of the steel pipe and the strength of the concrete are determined according to the stress conditions of the actual project; the UHPC butterfly web is a prefabricated plate, and a certain amount of space is reserved on the upper and lower edges of the web. A large number of bolt holes and steel bar holes. In order to prevent stress concentration, arc transition sections are set in the middle of both sides of the web. The UHPC strength and structural dimensions of the web are determined according to the actual engineering stress conditions and the arch ring structure; the cross-connected steel pipe It is used to connect the transverse chords, and the layout can be determined according to the construction requirements of the arch ring; the temporary steel web bars are used to connect the upper and lower chords, and a small number of straight web bars are arranged at a certain distance in each rigid skeleton segment. The number and arrangement spacing can be determined according to the construction requirements of the arch ring; the stirrups of the outer concrete roof and floor need to pass through the reserved steel holes in the web to improve the shear resistance of the interface between the web and the concrete roof and floor. The layout of the stirrups determines the spacing of reserved steel holes in the web; the size and hole spacing of the perforated steel plate at the joint between the web and the chord must be determined according to the stress conditions of the node. Considering the web installation, a perforated steel plate can be taken between adjacent steel web bars to leave an installation opening slightly larger than the width of the web; the perforated steel plate and UHPC butterfly web on the web and chord joint Through bolt connection, the bolts generally use high-strength bolts, and the size and number of the bolts are determined according to the stress of the node. The structure of the invention is novel, has good mechanical properties, and is relatively simple to construct. It can better solve the problems of a large number of rigid skeleton webs and difficult web pouring during traditional Meilan arch construction. It also combines butterfly-shaped and UHPC materials. The self-weight of the arch ring can be reduced to a great extent. Therefore, while meeting the load-bearing capacity requirements of Meilan Arch, it can save a large amount of steel, reduce the structure's dead weight, improve construction efficiency and structural durability, making the long-span Meilan Arch Bridge more economical and has a very wide range of application prospects.

The above preferred embodiments further describe the purpose, technical solutions and advantages of the present invention in detail. It should be understood that the present invention is not limited to the above preferred embodiments, and anyone can do so under the inspiration of the present invention. The Meilan arch structures and construction methods of various web forms are obtained. All equivalent changes and modifications made in accordance with the patentable scope of the present invention shall be included in the protection scope of the present invention.

Claims (8)

1. An assembled UHPC web flange arch structure based on a truss type structural form is characterized in that: comprises a steel pipe concrete chord pipe (1), a UHPC butterfly web (2), a transverse steel pipe (3) and a web and chord pipe joint (6); the steel pipe concrete chord pipe comprises two steel pipe concrete chord pipes (1) which are arranged in parallel and are arranged on the upper portion, transverse steel pipes (3) are vertically and fixedly connected between the two steel pipe concrete chord pipes (1) which are arranged in parallel and are arranged on the lower portion, the steel pipe concrete chord pipes (1) which are arranged on the upper portion in the same vertical face are connected with the steel pipe concrete chord pipes (1) which are arranged on the lower portion through UHPC butterfly webs (2), the steel pipe concrete chord pipes (1) are connected with UHPC butterfly webs (2) through webs and chord pipe joints (6), and the webs are connected with the chord pipe joints (6) through perforated steel plates (7) welded on the steel pipe concrete chord pipes (1) and the UHPC butterfly webs (2) through bolts (8) to form joints.

2. The truss-based structural style assembled UHPC web metaland arch construction of claim 1, wherein: the steel tube concrete chord tube (1), the transverse steel tube (3), the web and the periphery of the chord tube joint (6) are coated with a concrete top and bottom plate (5), a top and bottom plate stirrup (9), a top and bottom plate longitudinal bar (10) and concrete are arranged in the concrete top and bottom plate (5), and the top and bottom plate stirrup (9) passes through a web reserved steel bar hole (11) reserved by the UHPC butterfly web (2) so as to improve the shearing resistance of the interface of the UHPC butterfly web (2) and the concrete top and bottom plate (5).

3. The truss-based structural style assembled UHPC web metaland arch construction of claim 1, wherein: the steel pipe concrete chord pipe (1) is formed by curing steel pipe filled concrete.

4. The truss-based structural style assembled UHPC web metaland arch construction of claim 1, wherein: the steel pipe concrete chord tube is characterized in that two parallel and spaced perforated steel plates (7) are welded on the steel pipe concrete chord tube (1), the distance between the two parallel and spaced perforated steel plates (7) is smaller than the diameter of the steel pipe concrete chord tube (1), the UHPC butterfly web (2) is inserted between the two parallel and spaced perforated steel plates (7), and the bolts (8) are fixedly locked through holes in the perforated steel plates (7) and the UHPC butterfly web (2).

5. The truss-based structural style assembled UHPC web metaland arch construction of claim 1, wherein: the UHPC butterfly web (2) is a precast slab, and a plurality of holes for installing high-strength bolts (8) and web reserved steel bar holes (11) are reserved at the upper edge and the lower edge of the UHPC butterfly web (2).

6. The truss-based structural style assembled UHPC web metaland arch construction of claim 1, wherein: the width dimension of the middle parts of two sides of the UHPC butterfly web plates (2) is smaller than the width dimension of the upper part and the lower part, the middle parts of two sides of the UHPC butterfly web plates (2) are provided with arc transition sections, and the side parts of two adjacent UHPC butterfly web plates (2) form a fusiform hollow.

7. The truss-based structural style assembled UHPC web metaland arch construction of claim 1, wherein: a temporary steel web member (4) is further arranged between the steel tube concrete chord tube (1) positioned at the upper part and the steel tube concrete chord tube (1) positioned at the lower part in the same vertical face, and the temporary steel web member (4) and the UHPC butterfly web plate (2) are arranged in a staggered mode in the length direction of the steel tube concrete chord tube (1).

8. A construction method of an assembled UHPC web plate flange arch structure based on a truss type structural form comprises the following steps:

(1) The method comprises the steps of building a hoisting device according to the design size and the requirement, and processing a steel pipe concrete string pipe (1), a temporary steel web member (4) and a transverse steel pipe (3) in a prefabrication factory while building the hoisting device, and welding the transverse steel pipe (3), the temporary steel web member (4) and a steel plate with holes (7) on the steel pipe concrete string pipe (1) to form a stiff skeleton section;

(2) The UHPC butterfly web (2) is prefabricated in parallel while the stiff skeleton segment is processed, and the work is completed before the hoisting work begins;

(3) After the hoisting device is erected, hoisting the rigid skeleton segment and fixing the rigid skeleton segment to a design position;

(4) After the stiff skeleton segment is installed, hoisting the UHPC butterfly web plates (2), sliding a reserved installation opening formed between two perforated steel plates (7) into a design position between an upper steel pipe concrete chord tube (1) and a lower steel pipe concrete chord tube (1), enabling bolt holes on the UHPC butterfly web plates (2) to be in butt joint with the perforated steel plates (7) on the steel pipe concrete chord tube (1), connecting the two plates by using high-strength bolts (8), wherein the UHPC butterfly web plates (2) are discontinuously arranged, and gaps are reserved between the upper edges and the lower edges of the UHPC butterfly web plates (2) and the steel pipe concrete chord tube (1);

(5) After the UHPC butterfly web 2 of one section is assembled, the installation work of the next section can be carried out, and the work of the step (4) is repeated;

(6) The instantaneous closure device is adopted for closure, the line shape and the position of the main arch ring are comprehensively checked and adjusted before closure, an operator is required to perform double-rib simultaneous closure during closure, and after the arch ribs are closed to form a complete arch ring, concrete in the steel pipe concrete chord pipe is poured;

(7) And when the strength of the concrete in the pipe reaches a certain degree, removing the buckling ropes and the temporary steel web members (4), binding the top and bottom plate stirrups (9) and the top and bottom plate longitudinal ribs (10) of the top and bottom plate (5) and installing the templates, and finally pouring the concrete of the top and bottom plates (5).