CN101195989A - Construction technology of prefabricated bridge based on three steel pipe truss segments - Google Patents

Abstract

The invention discloses a prefabricated bridge construction process based on three types of steel tube truss segments. First, the substructure of the bridge is constructed, and then the superstructure is constructed. First, prefabricated multiple truss segments are sequentially erected on the substructure and assembled to form a bridge load-bearing structure. Finally, the bridge deck is laid to complete the bridge construction. The upper and lower chords of the truss segments are connected as a whole through a web member. Before prefabricating multiple truss segments that form the load-bearing structure, the stress conditions of each truss segment should be analyzed first, and they are divided into three types according to the stress, namely, empty steel tube truss segments in which both the upper chord and the lower chord are not filled with concrete, steel tube truss segments in which the compressed upper chord or the lower chord is filled with concrete alone, and steel tube truss segments in which both the upper chord and the lower chord are filled with concrete. The invention has a simple construction process, reasonable stress on the constructed bridge structure, and a wide range of applications. It can effectively solve the construction, cost, and engineering quality problems in bridge construction, and has good economic benefits.

Description

Construction technology of prefabricated bridge based on three steel pipe truss segments

technical field

The invention relates to the technical field of bridge construction, in particular to an assembled bridge construction process based on three steel pipe truss segments.

Background technique

At present, the domestic bridge construction forms are mainly prestressed concrete structures, steel trusses, and steel box girder structures, and steel pipe concrete structures and steel pipe truss structures are also widely used in existing bridge construction projects. Although the above-mentioned bridge structures have many advantages and are suitable for different bridge construction environments, these structures also have some relatively large defects. For example, the specific strength of prestressed concrete box girders is small due to the specific strength of structural materials (material strength/material bulk density), the dead load accounts for a large proportion of the total load, and the utilization efficiency of bearing capacity is low, so that it cannot meet the needs of long-span bridges; therefore In practice, in order to reduce the self-weight, the web of the bridge usually needs to be equipped with a large number of prestressed steel bars, so that the construction requires a large number of complex mechanical equipment, and the construction site is large and the construction period is long. However, the steel truss girder uses a large amount of steel, the overall structure rigidity is small, and the joint structure is complex. In addition, the performance of its joints is not guaranteed, the safety factor is low, and maintenance measures such as reinforcement are required on a regular basis. The service life is limited and the steel is completely used to withstand pressure. Not economical either. For the steel box girder structure, the steel consumption is also large and the welding requirements are high, which is not convenient for on-site fabrication, assembly and erection, and is not suitable for construction in mountainous and canyon areas.

Contents of the invention

The technical problem to be solved by the present invention is to provide a prefabricated bridge construction process based on three steel pipe truss segments in view of the above-mentioned deficiencies in the prior art. , can effectively solve the construction, cost and project quality problems in bridge construction.

In order to solve the above-mentioned technical problems, the technical solution of the present invention is: a kind of prefabricated bridge construction technology based on three kinds of steel pipe truss segments, first construct the substructure of the bridge, including the abutment 7 and pier for supporting the superstructure of the bridge. 8 and the foundation used to bear the downward pressure of the two; secondly, construct the superstructure of the bridge, including the load-bearing structure and the bridge deck 16. The upper and lower chords 1 and 2 of the truss segments are fixed and connected as a whole through the webs 3, and the multi-sections of the load-bearing structure are prefabricated. Before the steel pipe truss segments, the stress of each truss segment in the entire bridge load-bearing structure should be analyzed first. According to the force analysis, the multi-segment steel pipe truss segments are divided into three types, that is, for the For truss segments with no pressure on rod 2 or less pressure, the empty steel pipe truss segment with no concrete filling in upper chord 1 and lower chord 2 shall be used. The segment adopts the steel pipe truss segment with the upper chord 1 or the lower chord 2 under pressure filled with concrete alone, and the upper chord 1 and the lower chord 2 are all filled with concrete for the truss segment with both the upper chord 1 and the lower chord 2 under greater pressure After the prefabrication is completed, the prefabricated multi-segment steel pipe truss segments are fixedly connected and assembled to form the entire truss structure, that is, the load-bearing structure of the bridge, according to the force conditions at the factory or construction site.

As a preferred solution of the present invention, the upper chord 1 and the lower chord 2 of the three types of steel pipe truss segments are welded into one body through the web 3, and the web 3 is an empty steel pipe.

As another preferred solution of the present invention, the upper chord 1 , the lower chord 2 and the web 3 are rectangular, square or circular steel pipes.

As yet another preferred solution of the present invention, the three types of steel pipe truss segments are connected by means of flanges 4 or welded to form an integral truss structure.

As a further preferred solution of the present invention, the truss structure composed of the three types of steel pipe truss segments is two, three or multiple trusses, and the truss structures of each truss are connected by transverse connecting rods 5 .

As a further preferred solution of the present invention, every two truss structure transverse links 5 formed by the three types of steel pipe truss segments form a combined truss, and one, two or more combined trusses form an overall truss structure .

As yet another preferred solution of the present invention, the three steel pipe truss segments are generally in the shape of a straight line or an arc.

To sum up, the adoption of a prefabricated bridge construction process based on three steel pipe truss segments of the present invention has the following advantages: 1. The construction process is simple, the processing and construction are convenient, and there are few restrictions on the external construction environment, so it is suitable for various bridges The construction environment; 2. The scope of application is wide, and it is suitable for the construction of bridges with various structural forms; 3. The bridges built are of good quality and low cost. The bridge structure has light weight and strong spanning ability. Compared with traditional steel trusses, this The structure is simple, the steel consumption is low, the overall structure rigidity is large, the joint performance is good, and it is easy to apply prestress; 4. The three steel pipe truss segments used are easy to standardize in the factory, and it is easy to assemble and erect on site, especially in mountainous canyons 5. The structural performance of the bridge constructed with three steel pipe truss sections is stable. The arch bridge of this structure can use empty steel pipe sections in the vault area, which is beneficial to improve the stability of the bridge structure. Compared with the traditional CFST arch bridge, its structure is simple, the construction is convenient, and the concrete filling quality is good; 6. It is applied to external prestressed bridge structure systems such as cable-stayed bridges and self-anchored suspension bridges. By making full use of the compressive properties of CFST , thereby greatly reducing the amount of steel used.

The technical solutions of the present invention will be described in further detail below with reference to the accompanying drawings and embodiments.

Description of drawings

Fig. 1 is a schematic diagram of a girder bridge structure based on three straight steel pipe truss segments according to the first preferred embodiment of the present invention.

Fig. 2 is a schematic diagram of the structure of an arch bridge based on three arc-shaped steel pipe truss segments according to the second preferred embodiment of the present invention.

Fig. 3 is an enlarged structural schematic diagram of the combined joint P of steel pipe truss segments in Fig. 1 or Fig. 2 .

Fig. 4 is an enlarged structural schematic diagram of the combined joint Q of steel pipe truss segments in Fig. 1 or Fig. 2 .

Fig. 5 is a structural schematic diagram of a mid-through arch bridge based on three steel pipe truss segments according to the third preferred embodiment of the present invention.

Fig. 6 is a schematic structural diagram of a cable-stayed bridge based on three steel pipe truss segments according to a third preferred embodiment of the present invention.

Fig. 7 is a schematic structural diagram of a suspension bridge based on three steel pipe truss segments according to the third preferred embodiment of the present invention.

Fig. 8 is a schematic diagram of the longitudinal structure of the eight-girder bridge based on three steel pipe truss segments according to the present invention.

Explanation of reference signs:

1-top chord; 2-bottom chord; 3-web bar;

4-flange; 5-horizontal connecting rod; 6-support;

7-Abutment; 8-Pier; 9-Main arch;

10-column; 11-suspension rod; 12-main beam;

13-cable; 14-tower; 15-anchor;

16-deck; 17-foundation; 18-bolt.

Detailed ways

The first preferred embodiment, as shown in Figure 1, in the construction of the girder bridge based on three straight steel pipe truss sections, first construct the substructure of the bridge, that is, three supports 6 for supporting the superstructure of the bridge Secondly, construct the upper structure of the bridge, including load-bearing structure and bridge deck 16, prefabricate the multi-section truss segments that form the bridge load-bearing structure earlier, then erect it on the lower structure in turn and connect and assemble to form the bridge load-bearing structure, and finally lay the bridge Surface 16 completes the construction of the entire bridge. The upper chord 1 and the lower chord 2 of the truss segment are welded together through the web 3, and all three are rectangular steel pipes. Before prefabricating the multi-segment steel pipe truss segments that make up the load-bearing structure, the stress situation of each truss segment in the entire bridge load-bearing structure should be analyzed first, and the multi-segment steel pipe truss segments are divided into three types according to the force analysis , that is, for the truss segments with no pressure on the upper chord 1 and the lower chord 2 or with less pressure, the empty steel pipe truss segments with no concrete filling in the upper chord 1 and the lower chord 2 are used. For the truss segment under high pressure alone, the steel pipe truss segment with the upper chord 1 or the lower chord 2 filled with concrete alone is used. 2 Steel pipe truss segments filled with concrete; after prefabrication is completed, the prefabricated multi-segment steel pipe truss segments are fixedly connected and assembled to form the load-bearing structure of the bridge according to the force conditions during the factory or on-site construction.

In the load-bearing structure of the entire girder bridge shown in Figure 1, the stress of each part is that the upper chord 1 is under a greater pressure alone or the lower chord 2 is under a greater pressure alone, so only one type of steel pipe truss section is simply selected. Section, that is, the steel pipe truss segment in which the upper chord 1 or the lower chord 2 under compression is filled with concrete alone, and the web 3 is an empty steel pipe. Combined with Fig. 3 and Fig. 4, the upper chord 1 or the lower chord 2 of the adjacent steel pipe truss segments are filled with concrete alternately, and then the prefabricated multi-section steel pipe truss segments are connected by flanges 4 to form an overall truss structure, that is, a load-bearing structure , finally erected on the three supports 6 at the two ends and the center of the beam bridge, and finally lay the bridge deck 16 on the entire load-bearing structure to complete the follow-up work. The girder bridge assembled in this way can not only ensure good bearing performance, but also has a simple manufacturing process, saving time and materials.

In the second preferred embodiment, as shown in Figure 2, the construction process of the arch bridge based on three arc-shaped steel pipe truss segments is the same as that in the first preferred embodiment, and the load-bearing structure of the bridge, that is, the main arch part, is also made of multi-section prefabricated three Two types of steel pipe truss segments are assembled according to the stress of the bridge structure. The steel pipe truss segments are composed of upper chord 1, lower chord 2 and web 3, and the upper chord 1 and lower chord 2 are welded by web 3. Integrate and all three are rectangular steel pipes. Compared with beam bridges, arch bridges not only bear the load in the vertical direction, but also bear the force in the horizontal direction.

First, analyze the stress of each truss segment in the entire bridge load-bearing structure, and divide the multi-segment steel pipe truss segments into three types according to the force analysis, that is, neither the upper chord 1 nor the lower chord 2 is under pressure Or the hollow steel pipe truss segment with upper chord 1 and lower chord 2 not filled with concrete is used for the truss segment with less pressure, and the upper chord 1 or lower chord 2 is used for the truss segment with higher pressure alone The lower chord 2 is a steel pipe truss segment filled with concrete alone, and the upper chord 1 and lower chord 2 are all filled with concrete for the truss segment where the upper chord 1 and lower chord 2 are under greater pressure; after prefabrication is completed, During the factory or on-site construction process, the prefabricated multi-segment steel pipe truss segments are fixedly connected and assembled to form the load-bearing structure of the bridge according to the stress situation. In the construction of arch bridges, according to the force characteristics, the pressure on the center of the vault is relatively small, so this part chooses the empty steel pipe truss segment with no concrete filling in the upper chord 1 and the lower chord 2; from the center of the vault Gradually outward, the upper chord 1 of each steel pipe truss segment needs to bear the load pressure gradually increases, so the steel pipe truss segment with the upper chord 1 filled with concrete alone is selected; the closer to the bottom of the main arch, due to the influence of the bottom support, etc. The pressure to be borne by the lower chord 2 is also gradually increasing, so the steel pipe truss segments in which the upper chord 1 and the lower chord 2 are all filled with concrete are selected, and the web members 3 are all empty steel pipes. Combined with Figure 3 and Figure 4, the prefabricated multi-segment three types of arc-shaped steel pipe truss segments are connected by flanges 4 to form an overall truss structure, and bolts 18 are used to fix the flanges 4, and then the overall truss structure Go up and put bridge deck 16 and finish follow-up work and get final product.

The third preferred embodiment, as shown in Figure 5, the construction of the intermediate-supported arch bridge based on three kinds of arc-shaped steel pipe truss segments is the same as that of the first and second preferred embodiments. Abutment 7 and its support 6, and then the load-bearing structure of the bridge is erected on the abutment 7. The load-bearing structure of the bridge, that is, the main arch 9 is also assembled from three types of prefabricated steel pipe truss segments according to the stress of the bridge structure. The upper chord 1 and the lower chord 2 are welded together through the web 3 and all three are rectangular steel pipes. If only for people to walk, the required pressure of the arch bridge is less, then the bridge deck 16 can be directly laid on the curved main arch 9 . But the arch bridge deck 16 that modern vehicles pass through must keep certain straightness, can not be directly paved on the arc-shaped main arch 9. The supporting part of the arch bridge not only bears the pressure in the vertical direction, but also bears the force in the horizontal direction. Therefore, arch bridges have higher requirements on abutment 7 and foundation 17 than girder bridges. And a part of the bridge deck 16 of the middle bearing type arch bridge is above the main arch 9, and a part is below the main arch 9, and the bridge deck 16 will be indirectly supported by the column 10 or the suspension rod 11. The main arch 9 is erected on the abutments 7 at both ends, and the two ends of the bridge deck 16 are respectively fixed on two supports 6 .

In the construction of this intermediate arch bridge, a part of the arch bridge deck 16 is above the main arch 9, and this part of the bridge deck 16 is supported by vertical columns 10 connected and fixed on the foundation 17 and the main arch 9; Below the arch 9, this part of the bridge deck 16 is supported by vertical suspension rods 11 connected and fixed on the main arch 9. Similarly, firstly analyze the stress situation of the upper chord 1 and the lower chord 2 of each steel pipe truss segment. According to the stress analysis, the main arch 9 is in the part above the bridge deck 16, and the load borne by the center of the vault The pressure is relatively small, so the empty steel pipe truss segment in which the upper chord 1 and the lower chord 2 are not filled with concrete is selected; the upper chord 1 and the lower chord 2 pass through the suspender 11 gradually outward from the center of the top and close to the bridge deck 16 The pressure to be withstood gradually increases, so it is necessary to adopt a steel pipe truss segment in which the upper chord 1 and the lower chord 2 are all filled with concrete, and the web 3 is an empty steel pipe. For the part of the main arch 9 below the bridge deck 16, the upper chord 1 and the lower chord 2 need to bear a lot of pressure through the column 10, so the steel pipe truss segment in which the upper chord 1 and the lower chord 2 are all filled with concrete is selected. Bar 3 is empty steel pipe. Combined with Figure 3 and Figure 4, the prefabricated multi-segment three types of arc-shaped steel pipe truss segments are connected by flanges 4 to form an overall main arch 9 truss structure, and bolts 18 are used to fix the flanges 4, and then the bridge is laid Face 19 to complete the follow-up work.

The fourth preferred embodiment, as shown in Figure 6, the construction process of the cable-stayed bridge based on the three linear steel pipe truss segments is the same as the above three preferred embodiments, first constructing the substructure of the bridge, including fixing the main girder 12 Two piers 8 and two bearings 6 at both ends, and then the load-bearing structure of the fixed bridge is erected on the substructure. The load-bearing structure of the bridge, that is, the main girder 12, is also assembled from three types of prefabricated steel pipe truss segments according to the stress of the bridge structure. The upper chord 1 and the lower chord 2 are welded together through the web 3 and all three are rectangular steel pipes.

In the construction of this cable-stayed bridge, the two ends of the load-bearing structure are erected on two supports 6 fixed on the foundation 17, and the middle part is supported by two vertical piers 8 fixed on the foundation 17. Two vertical towers 14 are fixed above the main girder 12 relative to the two piers 8, and a plurality of cables 13 are symmetrically connected between the two sides of the two towers 14 and the load-bearing part, that is, the main girder 12. . Similarly, firstly analyze the stress situation of the upper chord 1 and the lower chord 2 of each steel pipe truss segment. According to the force analysis, the load-bearing structure, that is, in each steel Both need to bear the large horizontal pressure from the upper load, so the top chord 1 of all its steel pipe truss segments are filled with concrete. Specifically, in the part close to the tower 14, the upper chord 1 and the lower chord 2 need to bear the horizontal pressure from the cable 13 at the same time, so this part uses a steel pipe truss segment in which the upper chord 1 and the lower chord 2 are all filled with concrete; The load-bearing part is the middle part and both ends of the main girder 12. The upper chord 1 needs to bear greater load pressure, while the lower chord 2 bears less pressure. Therefore, the steel pipe truss segment in which the upper chord 1 is filled with concrete alone is selected. For the part of the tower 14, according to the force analysis, the upper chord 1 and the lower chord 2 of the part close to the main beam 12 need to bear the heavy vertical pressure from the cable 13 and the tower 14, so the upper chord 1 and the lower chord are selected The steel pipe truss segment of the rod 2 is filled with concrete; for the upper part of the tower 14, because the upper chord 1 and the lower chord 2 bear less vertical pressure from the cable 13 and the tower 14's own weight, the upper chord 1 and the lower chord 2 are selected 2 are empty steel pipe truss segments that are not filled with concrete, and the web members 3 of each steel pipe truss segment are empty steel pipes. Combined with Figure 3 and Figure 4, the prefabricated multi-segment three types of arc-shaped steel pipe truss segments are connected by flanges 4 to form an overall main girder 12 truss structure, and bolts 18 are used to fix flanges 4, and then the bridge is laid Face 16 and complete the follow-up work.

In the fifth preferred embodiment, as shown in Figure 7, the construction process of the suspension bridge based on the three linear steel pipe truss segments is the same as the above four preferred embodiments. There are two piers 8 and two supports 6 at both ends, and then the load-bearing structure of the fixed bridge is erected on the substructure. The load-bearing structure of the bridge, that is, the main girder 12, is also assembled from three types of prefabricated steel pipe truss segments according to the stress of the bridge structure. The upper chord 1 and the lower chord 2 are welded together through the web 3 and all three are rectangular steel pipes.

The construction of the suspension bridge is generally the same as that of the cable-stayed bridge. The two ends of the load-bearing part are erected on two supports 6 fixed on the foundation 17, and the middle part is supported by two vertical piers 8 fixed on the foundation 17. Two vertical towers 14 are fixedly arranged above the load-bearing part, that is, the main girder 12 , relative to the two bridge piers 8 . Simultaneously, a cable 13 is set up between the tops of the two towers 14 , and a cable 13 is drawn outwards from the top of each tower 14 and anchored on the anchorage 15 at the two ends of the main beam 12 . In this way, cables 13 are set up above the entire main girder 12, and a plurality of suspenders 11 are evenly connected and fixed between the cables 13 and the main girder 12.

Similarly, firstly analyze the stress situation of the upper chord 1 and the lower chord 2 of each steel pipe truss segment. According to the force analysis, the load-bearing structure, that is, in each steel They all need to bear the large horizontal pressure from the upper load, so the top chord 1 of all steel pipe truss segments needs to be filled with concrete. Specifically, for the part close to the tower 14, the lower chords of each steel pipe truss segment need to bear a large level of pressure, that is, both the upper chord 1 and the lower chord 2 in this part need to bear a lot of pressure at the same time, so This part adopts steel pipe truss segments in which the upper chord 1 and the lower chord 2 are all filled with concrete; for the load-bearing part, that is, the middle part and both ends of the main girder 12, the force to be borne is relatively small, and only the upper chord 1 needs The lower chord 2 bears less pressure, so the steel pipe truss segment in which the upper chord 1 is filled with concrete alone is selected. For the part of the tower 14, the upper chord 1 and the lower chord 2 of the part close to the main beam 12 need to bear the large vertical pressure from the cable 13 and the tower’s own weight through the suspender 11, so the upper chord 1 and the lower chord 2 are selected. A steel pipe truss segment filled with concrete; for the upper part of the tower 14, because the upper chord 1 and the lower chord 2 bear less vertical pressure from the cables 13 and the tower’s own weight through the suspender 11, the upper chord 1 and the lower chord 2 are selected The rods 2 are empty steel pipe truss segments that are not filled with concrete, and the web members 3 of each steel pipe truss segment are empty steel pipes. Combined with Figure 3 and Figure 4, the prefabricated multi-segment three types of arc-shaped steel pipe truss segments are connected by flanges 4 to form an overall main girder 12 truss structure, and bolts 18 are used to fix flanges 4, and then the bridge is laid Face 16 and complete the follow-up work.

In summary, in the above five preferred embodiments of the present invention, no matter it is an arch bridge, a cable-stayed bridge, or a suspension bridge, it can be built into two, three or more bridges according to actual needs, so as to increase the stability of the built bridge and increase the stability of the bridge. Bearing capacity of large bridges. As shown in Figure 8, the eight truss girder bridge is composed of four combined trusses to form an overall truss structure, and each truss structure of each combined truss is connected by a horizontal connecting rod 5, and each steel pipe is connected by a horizontal connecting rod 5 The upper chords 1 and the lower chords 2 of the truss segments are connected and fixed. Finally, lay the bridge deck 16 on the overall truss structure and complete the follow-up work.

The above are only preferred embodiments of the present invention, and do not limit the present invention in any way. All simple modifications, changes and equivalent structural changes made to the above embodiments according to the technical essence of the present invention still belong to the technical aspects of the present invention. within the scope of protection of the scheme.

Claims (7)

1. A prefabricated bridge construction process based on three steel pipe truss segments, first constructing the substructure of the bridge, including an abutment (7) for supporting the superstructure of the bridge, piers (8) and for carrying both The foundation of the downward pressure; secondly, construct the upper structure of the bridge, including the load-bearing structure and the bridge deck (16). For the load-bearing structure of the bridge, the bridge deck (16) is finally laid to complete the construction of the entire bridge. The upper chord (1) and the lower chord (2) of the truss segment are fixedly connected as one through the web (3), and it is characterized in that: prefabricated Before forming the multi-segment steel pipe truss segments of the load-bearing structure, the stress situation of each truss segment in the entire bridge load-bearing structure should be analyzed first, and the multi-segment steel pipe truss segments are divided into three types according to the force analysis. That is, for the truss segments with no pressure on the upper chord (1) and lower chord (2) or less pressure, the empty steel pipe truss segments in which the upper chord (1) and the lower chord (2) are not filled with concrete are used. For the truss segment of the upper chord (1) or the lower chord (2) that is under relatively large pressure alone, the steel pipe truss segment that is filled with concrete by the upper chord (1) or the lower chord (2) under compression, for the upper chord (1 ) and the lower chord (2) are subjected to relatively high pressure, the steel pipe truss segment with the upper chord (1) and the lower chord (2) being filled with concrete; The prefabricated multi-segment steel pipe truss segments are fixedly connected and assembled to form the entire truss structure, which is the load-bearing structure of the bridge. 2. according to claim 1, based on the prefabricated bridge construction process of three kinds of steel pipe truss segments, it is characterized in that: the upper chord (1) and the lower chord (2) of the three types of steel pipe truss segments pass The web bar (3) is welded into one, and the web bar (3) is an empty steel pipe. 3. According to claim 1 or 2, the fabricated bridge construction process based on three steel pipe truss segments is characterized in that: the upper chord (1), the lower chord (2) and the web (3) are rectangular , square or round steel pipes. 4. according to claim 1 or 2 described based on three kinds of steel pipe truss section prefabricated bridge construction technology, it is characterized in that: said three types of steel pipe truss sections are flanged (4) or welded connected to form an overall truss structure. 5. According to claim 1 or 2, the fabricated bridge construction process based on three types of steel pipe truss segments is characterized in that: the truss structure composed of the three types of steel pipe truss segments is two, three or more Each truss structure is connected by a transverse connecting rod (5). 6. according to claim 5 based on the fabricated bridge construction technique of three kinds of steel pipe truss segments, it is characterized in that: every two truss structure transverse connecting rods (5) formed by the three types of steel pipe truss segments A composite truss is composed of one, two or more composite trusses to form an overall truss structure. 7. The fabrication process of bridge construction based on three steel pipe truss sections according to claim 1 or 2, characterized in that: the three steel pipe truss sections are generally in the shape of a straight line or an arc.

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