CN117344619A - Assembled steel-concrete combined structure bridge applicable to mountain environment and construction method - Google Patents

Abstract

The invention discloses an assembled steel-concrete combined structure bridge suitable for mountain environments, which comprises a foundation, a steel pipe concrete pier column, a combined pier top beam, a steel girder and a prefabricated bridge deck; the steel pipe concrete pier column comprises a prefabricated pier column steel shell and concrete poured in the prefabricated pier column steel shell; the combined pier top cross beam comprises a box beam with a prefabricated steel structure and concrete poured in the box beam, wherein the end part of the steel main beam and the top end of a steel shell of the prefabricated pier column are jointly poured in the box beam to form a fixedly connected pier Liang Chuanli node, the top surface of the steel main beam and the top surface of the box beam which are positioned on the same horizontal plane form a supporting surface, and the prefabricated bridge deck is paved on the supporting surface formed by the steel main beam and the box beam; the invention improves the overall stress performance of the traditional reinforced concrete combined bridge, has the advantages of matched quality of the upper and lower assembly components, smaller hoisting weight, fewer site construction procedures and easy operation, and can be better suitable for rapid and high-quality construction of the bridge under the condition of limited sites such as mountain environments and the like.

Description

Assembled steel-concrete combined structure bridge applicable to mountain environment and construction method

Technical Field

The invention relates to the field of bridge engineering, in particular to an assembled steel-concrete combined structure bridge applicable to mountain environments and a construction method.

Background

Along with popularization of bridge industrialization concepts and requirements of industrial policies, the occupation ratio of the prefabricated bridge in a newly built bridge is gradually improved. The steel-concrete composite structure bridge combines the advantages of the steel structure and the concrete structure, and has many applications in urban municipal and highway bridges. However, in mountain environments, the degree of bridge assembly is relatively low. Compared with plain and urban environments, the bridge construction condition is poor in mountain environments, large hoisting equipment is difficult to enter, linear limiting factors of the bridge are more, and the bridge with small radius and flat curves and large longitudinal slopes occupies a relatively high area. The bridge construction period is longer by adopting the traditional construction mode, the on-site construction quality is not easy to control, and the ecological environment of the mountain land is greatly destroyed, so that the assembled bridge structure suitable for the mountain land is necessary to be developed.

On the other hand, the existing steel-concrete composite structure is mainly applied to assembly of a bridge upper structure, but the application of bridge piers with composite structures is less. Due to the lack of system consideration and reasonable structural design on the full bridge stress, the obvious material performance advantages of the steel-concrete combined structure are not fully exerted, and the problems of low full bridge assembly degree, unmatched hoisting weight, non-systematic material application and the like are needed to be solved. Because the integral stress performance of the continuous rigid frame is better than that of the continuous beam, the design should preferentially adopt the structure of the bridge pier and the main girder consolidation, so as to be suitable for the complex road line type and boundary condition of the bridge under the mountain condition.

In order to further improve the assembly degree of the conventional span bridge in the mountain land and improve the integration, adaptability and integrity of assembled bridge components, the scheme provides an assembled steel-concrete combined structure bridge suitable for the mountain land environment and a construction method; an assembled bridge structure mainly comprising a steel pipe concrete pier column, a combined pier top beam and a reinforced concrete composite beam is integrated; the problems of poor overall stress performance, low material utilization efficiency, high field assembly operation difficulty, difficult control of components and assembly quality, low industrialized construction degree, poor landscape performance, high maintenance difficulty and the like of the conventional assembled concrete bridge at present are solved.

Disclosure of Invention

In view of the above, the invention aims to overcome the defects in the prior art, further improve the assembly degree of the conventional span bridge under the mountain condition, improve the integration, adaptability and integrity of assembled bridge components, and provide an assembled steel-concrete combined structure bridge applicable to the mountain environment and a construction method thereof; the assembly type bridge structure mainly comprising the steel pipe concrete pier column, the combined pier top beam and the reinforced concrete composite beam is integrated; the invention solves the problems of low assembly degree of the bridge under the existing mountain condition, and solves the problems of poor overall stress performance, low material utilization efficiency, high field assembly operation difficulty, difficult control of components and assembly quality, low industrialized construction degree, poor landscape performance, high maintenance difficulty and the like of the conventional assembled bridge.

The invention relates to an assembled steel-concrete combined structure bridge suitable for mountain environments and a construction method thereof, wherein the assembled steel-concrete combined structure bridge comprises a foundation, a steel pipe concrete pier column, a combined pier top beam, a steel girder and a prefabricated bridge deck; the foundation is fixed at a preset position, and the construction mode of the foundation is any one of the prior art, and is not repeated here; the steel pipe concrete pier column comprises a prefabricated pier column steel shell and concrete poured into the prefabricated pier column steel shell, the construction of the concrete pouring into the prefabricated pier column steel shell of the steel pipe concrete pier column reduces the complex process of site formwork erection, and the prefabricated pier column steel is a columnar steel pipe in the scheme, so that the transportation and site assembly are facilitated, and the control of the construction quality is facilitated; the combined pier top beam is supported on the foundation by the steel pipe concrete pier column to form the steel pipe concrete pier system according to the scheme; the combined pier top beam comprises a box beam with a prefabricated steel structure and concrete poured in the box beam, the bottom end of a steel shell of the prefabricated pier column is fixed on a foundation, the steel shell of the prefabricated pier column is welded and fixed with the box beam, the steel girder is welded and fixed with the box beam, the end part of the steel main beam and the top end of the steel shell of the prefabricated pier column are jointly poured in the box beam, the steel girder, the box beam and the steel shell of the prefabricated pier column are prefabricated steel structural members, the steel pipe concrete pier column, the combined pier top beam and the steel girder form a connecting node of the steel-concrete combined structure, namely the fixedly connected pier Liang Chuanli node, fully exerts the material performance, and has the characteristics of convenient transportation and installation of the prefabricated members, convenient and quick site construction, strong applicability to complex environments, small influence on environment, low manufacturing cost, economy, high industrialized construction degree and the like, the steel girder and the box girder are mutually perpendicular to each other, the connection reliability of the structure is improved, and the support reliability of the precast bridge deck slab is improved, the top surface of the steel girder and the top surface of the box girder are positioned on the same horizontal plane, the steel girder top surface and the box girder top surface positioned on the same horizontal plane form a supporting surface, the precast bridge deck slab is paved on the supporting surface and supported by the steel girder and the combined pier top cross beam, the structural stability is improved, the precast bridge deck slab is a plurality of blocks, the precast bridge deck slabs are arranged along the extending direction of the bridge body, the precast bridge deck slab is assembled with the steel girder and is fixedly formed into the steel-concrete superposed beam by pouring concrete, the precast bridge deck slab is a standardized precast member, the pier girder fixedly connecting system improves the structural integrity, the transverse connection between the steel girders is reduced, the difficulty of on-site assembly is reduced, and the overall smoothness of the bridge deck is excellent.

Further, the anti-collision device also comprises a prefabricated anti-collision guardrail assembled at the transverse end part of the prefabricated bridge deck, wherein the prefabricated anti-collision guardrail is assembled on the prefabricated bridge deck through a connecting assembly; the prefabricated anti-collision guardrail belongs to an auxiliary module in a bridge system, and the prefabricated configuration of the auxiliary module standard can be customized and produced in batches, so that the defect of cracking and scattering of traditional auxiliary facilities is avoided, standardized and rapid installation and use are facilitated, and rapid installation and later maintenance of the bridge auxiliary facilities are facilitated.

The connecting assembly comprises an embedded part and a locking part, wherein the embedded part is embedded in the prefabricated anti-collision guardrail, the embedded part is provided with a connecting end extending out of the prefabricated anti-collision guardrail, and the locking part is assembled on the connecting end and used for fixing the prefabricated anti-collision guardrail on the prefabricated bridge deck; in this scheme, the built-in fitting is the bolt, and the retaining member is the nut with the bolt adaptation, and the connection through nut and bolt is with prefabricated crash barrier fastening on prefabricated decking, is favorable to prefabricated crash barrier quick installation and later maintenance.

Further, the bottom surface of prefabricated crash barrier has along longitudinal extension's keyway, the top surface of prefabricated decking has along longitudinal extension's key, key and keyway adaptation promote the assembly convenience of prefabricated crash barrier on the prefabricated decking, structural strength and spacing intensity homoenergetic also can be promoted simultaneously, the link of built-in fitting is located the inslot of keyway.

Further, the top surface of the steel girder is provided with a shear pin group, the prefabricated bridge deck is provided with a notch for accommodating the shear pin group, and the steel girder and the prefabricated bridge deck form a whole through the fixation of the shear pin group in the notch; the cast-in-situ shear pin groups and the notch enable the prefabricated bridge deck to be further integrated with the steel main beam, so that the force transmission reliability is ensured;

the shear force nail crowd is prefabricated simultaneously with the steel girder, the notch is reserved when prefabricated decking is prefabricated.

Further, the shear force nail group comprises a plurality of shear force nails distributed on the top surface of the steel girder at set positions, the root parts of the shear force nails are fixed on the steel girder, and the head parts of the shear force nails are positioned in the notch and fixed on the prefabricated bridge deck;

the shear force nail group is a plurality of groups, the notch is a plurality of, the quantity of the shear force nail group is the same with that of the notch, and the shear force nail group is connected with the notch in a one-to-one correspondence.

Further, the box girder is internally provided with a reinforcing rib plate which is arranged close to the steel girder, the arrangement of the reinforcing rib can further improve the structural strength of the box girder, and the structural stability of the combined pier top beam, the steel girder and the steel pipe concrete pier post after being integrally formed can be further ensured; the reinforcement rib plates and the box beams are prefabricated at the same time; the reinforcing rib plate comprises a reinforcing transverse rib and a reinforcing longitudinal rib, the transverse ends of the reinforcing transverse rib respectively and correspondingly extend to a box beam transverse end plate which is transversely close to the reinforcing transverse rib, the longitudinal ends of the reinforcing longitudinal rib respectively and correspondingly extend to a box beam longitudinal end plate which is longitudinally close to the reinforcing longitudinal rib, the reinforcing transverse rib is provided with a transverse rib through hole, and the reinforcing longitudinal rib is provided with a longitudinal rib through hole, so that a box of the box beam is divided into a plurality of mutually communicated reinforcing chambers by the reinforcing transverse rib and the reinforcing longitudinal rib.

Further, the number of the steel tube concrete pier columns is several, and the steel tube concrete pier columns are uniformly distributed at the bottom of the box girder along the transverse direction; the bridge is characterized by further comprising a transverse connecting beam between the columns, wherein the transverse connecting beam between the columns is a prefabricated steel structural member, two transverse adjacent steel pipe concrete pier columns are connected by the transverse connecting beam between the columns to form a pier column joint group, the number of the steel pipe concrete pier columns arranged at the bottom of each combined pier top cross beam in the scheme is two, the two steel pipe concrete pier columns are connected by the transverse connecting beam between the columns to form the pier column joint group, a double-column steel pipe concrete structure is adopted, the section is a circular section, and then the supporting reliability and the integral aesthetic property of the bridge are improved.

Further, a concrete filled steel tube pier column limiting groove for assembling the concrete filled steel tube pier column is reserved on the foundation, and the concrete filled steel tube pier column is fixed to the foundation through the concrete filled steel tube pier column limiting groove.

Further, the steel tube concrete pier column further comprises a steel bar cage fixed at the bottom end of the prefabricated pier column steel shell, a plurality of reinforcing ribs are arranged at the connecting interface of the steel bar cage and the prefabricated pier column steel shell, and the reinforcing ribs are uniformly distributed in the circumferential direction of the connecting interface of the steel bar cage and the prefabricated pier column steel shell; prefabricating the reinforcement cage, the reinforcing ribs and the prefabricated pier column steel shells; and the assembly reliability of the steel pipe concrete pier column on the foundation is improved.

The scheme also discloses a construction method based on the assembled steel-concrete composite structure bridge applicable to the mountain environment, which comprises the following construction steps:

s1, constructing a foundation, wherein a steel pipe concrete pier column limiting groove for assembling a steel pipe concrete pier column is reserved at the top of the foundation;

s2, constructing a concrete filled steel tube pier column, and integrating the concrete filled steel tube pier column and a foundation;

the construction of the concrete filled steel tube pier column comprises the following steps:

s2a, pouring concrete at the bottom end of the steel pipe concrete pier column, and enabling the bottom end of a prefabricated pier column steel shell with a reinforcement cage and a plurality of reinforcing ribs to be limited in a steel pipe concrete pier column limiting groove so that the bottom end of the steel pipe concrete pier column and a foundation are poured to form a whole;

the bottom ends of two concrete filled steel tube pier columns in the pier column coupling group are respectively and correspondingly poured into the same limiting groove, so that the pier column coupling group is supported by the same foundation;

pouring concrete at the bottom end of the steel pipe concrete pier column, and enabling the top of the foundation to form a protection section wrapping the connection interface of the reinforcement cage and the prefabricated pier column steel shell, wherein the protection section protrudes out of the top surface of the foundation;

before pouring concrete at the bottom end of the steel pipe concrete pier column, erecting a template for defining the shape of the protection section on the top of the foundation;

S2, pouring concrete positioned at the upper part of the bottom end of the steel pipe concrete pier column in a prefabricated pier column steel shell, wherein a post-pouring section with a preset depth is reserved at the top end of the prefabricated pier column steel shell;

the height of the steel pipe concrete pier column is increased through superposition of prefabricated pier column steel shells;

when the prefabricated pier column steel shells are overlapped, clamping plates are arranged in the circumferential direction of the connecting interfaces of the adjacent prefabricated pier column steel shells, so that central axes of the prefabricated pier column steel shells spliced up and down are approximately overlapped, and the adjacent prefabricated pier column steel shells form a whole in a welding mode;

removing the clamping plates after the adjacent prefabricated pier stud steel shells are integrated;

s3, constructing a combined pier top beam and a steel girder, and integrating the combined pier top beam, the steel girder and a steel pipe concrete pier column;

before the combined pier top cross beam and the steel main beam are constructed, fixing the adjacent prefabricated pier column steel shells in the pier column coupling group through the inter-column transverse connecting beams of the prefabricated steel structure;

the construction of the combined pier top cross beam and the steel main beam comprises the following steps:

s3a, welding and fixing the box girder on the top end of the steel pipe concrete pier stud, enabling the box of the box girder to be communicated with the post-pouring section, wherein the top end of the prefabricated pier stud steel shell is positioned in the box of the box girder;

s3b, welding and fixing the steel main beam on the box beam, wherein the end part of the steel main beam is positioned in the box of the box beam;

S3c, pouring concrete in the box girder, and filling concrete in the box of the box girder and the post-pouring section of the steel pipe concrete pier, so that the steel pipe concrete pier, the steel girder and the box girder with the reinforced rib plates form a whole of a steel-concrete structure;

s4, constructing a prefabricated bridge deck, and integrating the prefabricated bridge deck, the combined pier top cross beam and the steel main beam;

the prefabricated bridge deck construction includes:

s4a, paving a prefabricated bridge deck supported by the steel girder and the combined pier top cross beam on the supporting surface, and limiting the prefabricated bridge deck by a shear nail group on the top surface of the steel girder through a notch;

s4b, pouring concrete in the notch, filling the concrete in the notch so that the shear nail group of the steel girder is fixedly connected in the notch of the prefabricated bridge deck through the concrete, and thus the prefabricated bridge deck and the steel girder form a whole;

s5, assembling the prefabricated anti-collision guardrail at the set position of the prefabricated bridge deck.

The beneficial effects of the invention are as follows: the assembled steel-concrete composite structure bridge and the construction method thereof, disclosed by the invention, integrate the assembled bridge structure mainly comprising the steel pipe concrete pier column, the combined pier top beam and the steel-concrete composite beam, improve the service efficiency of the structure and materials, facilitate the processing and manufacturing, the member transportation and the field assembly, solve the problems of poor adaptability of the conventional assembled bridge to the mountain environment, complex field assembly operation, low material utilization efficiency, large ecological environment damage, scattered accessory facility parts, large maintenance difficulty and the like, improve the assembly degree of the bridge in the mountain environment, have the advantages of reasonable structure, convenient construction, reasonable stress, economic manufacturing cost and attractive appearance, have higher economic and social values, and are novel integral assembled bridge structure worthy of popularization and use.

Drawings

The invention is further described below with reference to the accompanying drawings and examples:

FIG. 1 is a schematic diagram of the structure of the present invention;

FIG. 2 is a schematic structural view of the concrete filled steel tube pier system of the present invention;

FIG. 3 is a schematic structural view of the bottom end of the concrete filled steel tube pier column of the present invention assembled on a foundation;

FIG. 4 is a schematic view of the structure of the reinforced concrete composite beam of the present invention;

FIG. 5 is a schematic diagram of the front view of FIG. 4 according to the present invention;

FIG. 6 is a schematic view of a rigid-connection pier Liang Chuanli node in accordance with the present invention;

fig. 7 is a schematic view of the construction of the prefabricated crash barrier of the present invention assembled on a prefabricated deck slab.

Detailed Description

FIG. 1 is a schematic diagram of the structure of the present invention; FIG. 2 is a schematic view of a concrete filled steel tube pier of the present invention supporting a modular coping cross beam to a foundation; FIG. 3 is a schematic structural view of the bottom end of the concrete filled steel tube pier column of the present invention assembled on a foundation; FIG. 4 is a schematic view of the prefabricated deck slab of the present invention assembled on a steel main beam; FIG. 5 is a schematic diagram of the front view of FIG. 4 according to the present invention; FIG. 6 is a schematic view of the assembly of the top end of a concrete filled steel tube pier column of the present invention with a combined pier top beam and steel girder; FIG. 7 is a schematic view of the prefabricated crash barrier of the present invention assembled on a prefabricated deck slab, wherein the transverse direction is the width direction of the bridge body, and the longitudinal direction is the length direction of the bridge body, and the description thereof is omitted herein; the assembled steel-concrete composite structure bridge suitable for mountain land environment in the embodiment comprises a foundation 1, a steel pipe concrete pier column 2, a combined pier top beam 3, a steel girder 4 and a prefabricated bridge deck 5.

In this embodiment, the foundation 1 is fixed at a preset position, a concrete filled steel tube pier column limiting groove for assembling the concrete filled steel tube pier column 2 is reserved at the top of the foundation 1, and any one of the prior art is selected as a construction mode of the foundation 1, which is not described herein.

In this embodiment, the steel pipe concrete pier column 2 includes prefabricated pier column steel shell and the concrete of pouring in prefabricated pier column steel shell, and the construction of pouring concrete in the prefabricated pier column steel shell of steel pipe concrete pier column 2 makes the complex process of on-the-spot formwork reduced, and prefabricated pier column steel is the column steel pipe in this scheme, more does benefit to transportation and on-the-spot equipment, more does benefit to the quality of controlling the construction.

In this embodiment, the concrete filled steel tube pier column 2 further includes a reinforcement cage 21 fixed at the bottom end of the prefabricated pier column steel shell, a plurality of reinforcing ribs 22 are provided at the connection interface of the reinforcement cage 21 and the prefabricated pier column steel shell, and a plurality of reinforcing ribs 22 are uniformly distributed in the circumferential direction of the connection interface of the reinforcement cage 21 and the prefabricated pier column steel shell; the reinforcement cage 21 and the reinforcing ribs 22 are prefabricated with the prefabricated pier column steel shell, so that the assembly reliability of the steel tube concrete pier column 2 on the foundation 1 is improved.

In this embodiment, the steel pipe concrete pier column 2 supports the combined pier top beam 3 on the foundation 1 to form the steel pipe concrete pier system according to the present embodiment, the steel pipe concrete pier column 2 is fixed on the foundation 1 through the steel pipe concrete pier column limiting groove, more specifically, the steel pipe concrete pier column base of the steel pipe concrete pier column 2 with the reinforcement cage 21 and the reinforcement rib 22 forms a concreted whole with the foundation 1, during construction, the prefabricated pier column steel shell with the reinforcement cage 21 and the reinforcement rib 22 at the bottom is inserted into the steel pipe concrete pier column limiting groove reserved on the top surface of the foundation 1, and concrete is cast in place in the steel pipe concrete pier column limiting groove, so that the steel pipe concrete pier column 2 and the foundation 1 form a concreted whole, the construction positioning is convenient, and the assembly is easy; pouring concrete at the bottom end of the steel pipe concrete pier stud 2 to form a protection section 12 wrapping the connection interface of the reinforcement cage 21 and the prefabricated pier stud steel shell at the top of the foundation 1, wherein the protection section 12 protrudes out of the top surface of the foundation 1; the reliable force transmission of the column foot node is ensured, the protection section 12 wraps the exposed part reinforcing rib 22 of the column foot and the steel tube concrete pier column foot steel structure, the protection section 12 forms concrete wrapping the steel tube concrete pier column foot node in a pouring mode, and the column foot steel structure is prevented from being corroded due to water accumulation at the column foot part of the steel tube concrete pier column foot, so that the durability of the steel tube concrete pier column foot node is improved; before pouring concrete at the bottom end of the steel pipe concrete pier column 2, erecting a template for defining the shape of the protection section 12 on the top of the foundation 1, and dismantling the template for defining the shape of the protection section 12 after the column foot node of the steel pipe concrete pier column is fixedly connected to the foundation 1; the steel tube concrete pier columns 2 are distributed at the bottoms of the combined pier top cross beams 3 in the transverse direction; more specifically, a plurality of the steel tube concrete pier columns are uniformly distributed at the bottom of the box girder along the transverse direction.

In this embodiment, the beam further includes an inter-column transverse connection beam 23, the inter-column transverse connection beam 23 is a prefabricated steel structural member, and the prefabricated pier column steel shell and the inter-column transverse connection beam 23 can adopt an industrialized manufacturing mode, so that batch processing and field installation are facilitated; two steel pipe concrete pier columns 2 which are adjacent in the transverse direction are connected by a transverse connecting beam 23 between the columns to form a pier column joint group, and the connection mode is welding.

In the embodiment, two steel tube concrete piers 2 are arranged at the bottom of each combined pier top beam 3, the two steel tube concrete piers 2 are connected by a transverse connecting beam 23 between the two steel tube concrete piers to form a pier column joint group, and the bottom ends corresponding to the two steel tube concrete piers 2 in the pier column joint group are poured in the same limiting groove, so that the pier column joint group is supported by the same foundation 1; the double-column type steel pipe concrete structure is adopted, the section of the steel pipe concrete pier column 2 is a circular section, and therefore the supporting reliability and the overall aesthetic property of the bridge are improved.

In this embodiment, the height of the concrete filled steel tube pier column 2 is increased by overlapping the prefabricated pier column steel shells; so that the steel pipe concrete pier column 2 can be suitable for different bridge site heights, and the height of the steel pipe concrete pier column 2 is changed by adjusting the length and the number of the prefabricated pier column steel shell sections.

In the embodiment, when the prefabricated pier column steel shells are overlapped, clamping plates are arranged in the circumferential direction of the connecting interfaces of the adjacent prefabricated pier column steel shells, so that central axes of the prefabricated pier column steel shells spliced up and down are approximately overlapped, positioning accuracy between concrete section columns is guaranteed, and the adjacent prefabricated pier column steel shells form a whole in a welding mode; and removing the clamping plates after the adjacent prefabricated pier stud steel shells are integrated.

In this embodiment, the inter-column transverse connection beam 23 adopts separated transverse connection, is constructed and assembled on site flexibly, improves the transverse stability of the double-column type steel tube concrete pier system, and the vertical interval of transverse connection can be adapted to the vertical sectional dimension of the pier according to the length and the number of the prefabricated pier column steel shell sections, so that the manufacturing and the installation are convenient, and the view permeability under the bridge is better.

In this embodiment, the steel girder 4 and the combined pier top beam 3 are connected vertically, the connection reliability of the structure is improved, and the support reliability of the prefabricated pier column steel shell is improved, in this scheme, the steel girder 4 is a strip steel structure girder extending along the longitudinal direction, the steel girder 4 is uniformly distributed along the transverse direction to form a multi-ribbed support system, the steel girder 4 adopts a standard specification welding i-shaped section, the section is arranged, and can be overlapped along with the width of the bridge, thereby facilitating standardized production processing, the combined pier top beam 3 comprises a box girder 31 of the prefabricated steel structure and concrete cast in the box girder 31, the bottom end of the prefabricated pier column steel shell is fixed on a foundation, the prefabricated pier column steel shell is welded and fixed with the box girder 31, the end of the steel girder 4 and the top end of the prefabricated pier column steel shell are cast in the box girder 31 together, and the steel girder and the box girder 4 are connected vertically, as shown in fig. 4, 5 and 6, the corresponding end of the steel girder 4 in the multi-ribbed support system is more constrained by the steel girder, and the stress performance of the girder is improved; the steel main beam 4, the box beam 31 and the prefabricated pier column steel shell are all prefabricated steel structural members, so that the processing, the manufacturing, the member transportation and the field assembly are convenient, the box beam 31 can be used as a pier top cast-in-place concrete template and an operation platform, the bracket and the template operation are greatly reduced, the box beam 31 of the steel structure is semi-hidden, the tops of the steel main beam 4 and the steel pipe concrete pier column 2 are embedded into the box beam 31 and then are fixedly poured, the exposed size of a cross beam is smaller, the transverse middle part of a box beam bottom plate protrudes downwards, the reliability of a bridge fixedly system is improved, and meanwhile the aesthetic property of a bridge is improved; the steel pipe concrete pier column 2, the combined pier top cross beam 3 and the steel main beam 4 form a connecting node of a steel-concrete combined structure, so that the bridge span-space dense rib type steel main beam 4 beam is converted from a simply supported state to a consolidated state, and the full bridge forms a stress state of a continuous rigid frame, namely the fixedly connected pier Liang Chuanli node in the scheme, the material performance is fully exerted, and the steel pipe concrete pier has the characteristics of convenience in transportation and installation of prefabricated components, convenience and rapidness in site construction, strong applicability to complex environments, small influence on the environment, economic manufacturing cost, high industrialized construction degree and the like.

In this embodiment, the box beam 31 has a reinforcing rib plate 32 disposed near the steel girder 4, and the arrangement of the reinforcing rib 22 can further improve the structural strength of the box beam 31, and further ensure the structural stability of the combined pier top beam 3, the steel girder 4 and the steel pipe concrete pier column 2 after forming an integral body; in the scheme, the reinforcing rib plates 32 and the box beams 31 are prefabricated at the same time; the reinforcing rib plate 32 comprises a reinforcing transverse rib and a reinforcing longitudinal rib, the transverse ends of the reinforcing transverse rib respectively and correspondingly extend to the transverse end plates of the box girder which are transversely close to the reinforcing transverse rib, the longitudinal ends of the reinforcing longitudinal rib respectively and correspondingly extend to the longitudinal end plates of the box girder which are longitudinally close to the reinforcing longitudinal rib, the reinforcing transverse rib is provided with a transverse rib through hole, and the reinforcing longitudinal rib is provided with a longitudinal rib through hole, so that the box of the box girder 31 is divided into a plurality of mutually communicated reinforcing chambers by the reinforcing transverse rib and the reinforcing longitudinal rib, and the inside of the box girder 31 is reinforced.

In this embodiment, the top surface of the steel girder 4 and the top surface of the box girder 31 are located on the same horizontal plane, the steel girder top surface and the box girder top surface located on the same horizontal plane form a supporting surface, the prefabricated bridge deck 5 is laid on the supporting surface and supported by the steel girder 4 and the box girder 31, so as to promote structural stability, the prefabricated bridge deck 5 is a plurality of blocks, the prefabricated bridge deck 5 is arranged along the extending direction of the bridge body, and the prefabricated bridge deck is assembled with the steel girder and fixed by casting concrete, and the prefabricated concrete bridge deck adopts a rectangular body formed by adopting a uniform thickness section, so that the prefabricated bridge deck is convenient to manufacture and transport; the concrete bridge deck has strong adaptability to road line types, and can adapt to different road flat curve line types by modifying the radian and the length of the inner side line and the outer side line; the concrete bridge deck is provided with a notch 51 for accommodating the shear pin group 41, so that the shear pin group on the steel girder 4 is conveniently connected with the shear pin group to form a whole through pouring concrete; the steel-concrete composite beam is further formed, the prefabricated bridge deck plates 5 and the steel main beams 4 are standardized prefabricated components, the pier-beam fixedly-connecting system improves the structural integrity, reduces the transverse connection between the steel main beams, reduces the on-site assembly difficulty, and has excellent overall bridge deck smoothness; the integral stress performance of the traditional reinforced concrete combined bridge is improved, the quality of the upper and lower assembly components is matched, the hoisting weight is small, the site construction procedures are less, the operation is easy, and the method is well applicable to rapid bridge construction in mountain environments.

In this embodiment, the top surface of the steel main beam 4 is provided with a shear pin group 41, the prefabricated bridge deck 5 is provided with a notch 51 for accommodating the shear pin group 41, and the steel main beam 4 is integrally formed with the prefabricated bridge deck 5 through the fixation of the shear pin group 41 in the notch 51; the steel main beam 4 is connected with the precast bridge deck 5 of the concrete structure through a post-cast notch 51, and the precast bridge deck 5 is further integrated with the steel main beam 4 by cast-in-situ of the shear pin group 41 and the notch 51, so that the force transmission reliability is ensured; the end of the reinforced concrete composite beam is fixedly connected with the bridge pier, and a transverse-connection-free system is adopted, so that the number of on-site connection is reduced, and the on-site rapid assembly is facilitated; the shear pin group 41 and the steel main beam 4 are prefabricated at the same time, and the notch 51 is reserved when the prefabricated bridge deck 5 is prefabricated.

In this embodiment, the shear pin group 41 includes several shear pins distributed on the top surface of the steel girder 4 at a set position, the root parts of the shear pins are fixed on the steel girder 4, and the head parts of the shear pins are positioned in the notch 51 and fixed on the prefabricated bridge deck 5; the shear force nail group 41 is a plurality of groups, the notch 51 is a plurality of groups, the number of the shear force nail group 41 is consistent with that of the notch 51, and the shear force nail group 41 and the notch 51 are connected in a one-to-one correspondence.

In the embodiment, the anti-collision guardrail further comprises a prefabricated anti-collision guardrail 6 assembled at the transverse end part of the prefabricated bridge deck 5, wherein the prefabricated anti-collision guardrail 6 is assembled on the prefabricated bridge deck 5 through a connecting assembly; the prefabricated anti-collision guardrail 6 belongs to an auxiliary module in a bridge system, and the prefabricated configuration of the auxiliary module standard can be customized and produced in batches, so that the defect of cracking and scattering of traditional auxiliary facilities is avoided, standardized and rapid installation and use are facilitated, and rapid installation and later maintenance of the bridge auxiliary facilities are facilitated.

The connecting assembly comprises an embedded part 61 and a locking part 62, wherein the embedded part 61 is embedded in the prefabricated anti-collision guardrail 6, the embedded part 61 is provided with a connecting end extending out of the prefabricated anti-collision guardrail 6, and the locking part 62 is assembled on the connecting end and used for fixing the prefabricated anti-collision guardrail 6 on the prefabricated bridge deck 5; in this scheme, embedded part 61 is the bolt, and retaining member 62 is the nut with the bolt adaptation, and be connected through nut and bolt with prefabricated crash barrier 6 fastening on prefabricated decking 5, use the sealed screw thread mouth of safety cover after the stretch-draw is accomplished, make things convenient for prefabricated crash barrier 6 and prefabricated decking 5 to form wholly, be favorable to prefabricated crash barrier 6 quick installation and later maintenance.

In this embodiment, the bottom surface of prefabricated crash barrier 6 has along vertically extending's keyway, the top surface of prefabricated decking 5 has along vertically extending's key 52, key 52 and keyway adaptation promote the assembly convenience of prefabricated crash barrier 6 on prefabricated decking 5, and structural strength and spacing intensity homoenergetic also can be promoted simultaneously, the link of built-in fitting 61 is located the inslot of keyway.

The design and the manufacturing concept of integration and assembly are adopted in the scheme, so that the stress performance, the linear adaptability, the construction assembly degree and the landscape quality effect of the structure are improved.

The scheme also discloses a construction method based on the assembled steel-concrete composite structure bridge applicable to the mountain environment, which comprises the following construction steps:

s1, constructing a foundation 1, wherein a steel pipe concrete pier column limiting groove for assembling a steel pipe concrete pier column 2 is reserved at the top of the foundation 1;

s2, constructing the steel tube concrete pier column 2, and enabling the steel tube concrete pier column 2 and the foundation 1 to form a whole;

the construction of the steel tube concrete pier stud 2 comprises the following steps:

s2a, conveying a prefabricated pier column steel shell with a reinforcement cage 21 and a plurality of reinforcing ribs 22 at the bottommost end of a steel tube concrete pier column 2 to an area to be installed of a foundation 1, enabling the bottom end of the prefabricated pier column steel shell with the reinforcement cage 21 and the plurality of reinforcing ribs 22 to be limited in a steel tube concrete pier column limiting groove in advance, pouring concrete at the bottom end of the steel tube concrete pier column 2, and enabling the bottom end of the steel tube concrete pier column 2 and the foundation 1 to be poured into a whole;

The bottom ends of two concrete filled steel tube pier columns 2 in the pier column coupling group are respectively poured into the same limiting groove, so that the pier column coupling group is supported by the same foundation 1;

pouring concrete at the bottom end of the steel pipe concrete pier stud 2 to form a protection section 12 wrapping the connection interface of the reinforcement cage 21 and the prefabricated pier stud steel shell at the top of the foundation 1, wherein the protection section 12 protrudes out of the top surface of the foundation 1;

before pouring concrete at the bottom end of the steel pipe concrete pier column 2, erecting a template for defining the shape of the protection section 12 on the top of the foundation 1;

s2, pouring concrete positioned at the upper part of the bottom end of the steel pipe concrete pier column 2 in a prefabricated pier column steel shell, wherein a post-pouring section with a preset depth is reserved at the top end of the prefabricated pier column steel shell;

the height of the steel pipe concrete pier column 2 is increased through superposition of prefabricated pier column steel shells, concrete needs to be poured into the section of prefabricated pier column steel shells after each layer of prefabricated pier column steel shells are superposed, and concrete can be uniformly poured into the sections of prefabricated pier column steel shells after the height of the steel pipe concrete pier column 2 is determined, so that repeated description is omitted;

when the prefabricated pier column steel shells are overlapped, clamping plates are arranged in the circumferential direction of the connecting interfaces of the adjacent prefabricated pier column steel shells, so that central axes of the prefabricated pier column steel shells spliced up and down are approximately overlapped, and the adjacent prefabricated pier column steel shells form a whole in a welding mode;

Removing the clamping plates after the adjacent prefabricated pier stud steel shells are integrated;

s3, constructing a combined pier top beam 3 and a steel girder 4, and forming the combined pier top beam 3, the steel girder 4 and the steel pipe concrete pier column 2 into a whole;

before the combined pier top cross beam 3 and the steel main beam 4 are constructed, fixing adjacent prefabricated pier column steel shells in the pier column joint group through a transverse connecting beam 23 between the prefabricated pier column steel shells, wherein the fixing mode is welding, and the transverse connecting beam 23 between the pier columns is vertical to the prefabricated pier column steel shells;

the construction of the combined pier top cross beam 3 and the steel main beam 4 comprises the following steps:

s3a, conveying the box girder 31 to the top end of the steel pipe concrete pier stud, enabling a box of the box girder 31 to be communicated with the post-pouring section, welding and fixing the box girder 31 on a prefabricated pier stud steel shell positioned at the top end of the steel pipe concrete pier stud, wherein the top end of the steel pipe concrete pier stud 2 is positioned in the box of the box girder 31;

s3b, sequentially conveying a plurality of steel girders to the top ends of the steel pipe concrete pier columns, sequentially and respectively welding the steel girders at preset positions of the box girders 31 in a corresponding manner, and arranging adjacent steel girders in parallel to enable a plurality of steel girders 4 to be sequentially welded and fixed on the box girders 31, wherein the end part of each steel girder 4 is positioned in a box of the box girders 31;

s3c, pouring concrete in the box girder 31, and filling the concrete in the box of the box girder 31 and the post-pouring section of the steel pipe concrete pier column 2 so that the steel pipe concrete pier column 2, the steel main girder 4 and the box girder 31 with the reinforcing rib plates 32 form a whole of a steel-concrete structure;

S4, constructing prefabricated bridge decks 5, conveying a plurality of prefabricated bridge decks to the top of a supporting surface formed by the top surface of the steel girder and the top surface of the box girder, and enabling the prefabricated bridge decks 5, the combined pier top cross beam 3 and the steel girder 4 to form a whole one by one;

the prefabricated bridge deck 5 construction includes:

s4a, paving a prefabricated bridge deck 5 supported by the steel girder 4 and the combined pier top cross beam 3 on a supporting surface, and limiting the prefabricated bridge deck 5 by a shear pin group 41 on the top surface of the steel girder 4 through a notch 51;

s4b, pouring concrete in the notch 51, and filling the notch 51 with the concrete so that the shear nail group 41 of the steel girder 4 is fixedly connected in the notch 51 of the prefabricated bridge deck 5 through the concrete, thereby forming the prefabricated bridge deck 5 and the steel girder 4 into a whole;

s5, assembling the prefabricated anti-collision guardrails 6 at the set positions of the prefabricated bridge decks 5, more specifically, assembling a plurality of prefabricated anti-collision guardrails 6 at the set positions of the prefabricated bridge decks 5 corresponding to the prefabricated anti-collision guardrails one by one, and roughly positioning through the fit of key grooves and keys when the prefabricated anti-collision guardrails 6 are assembled, and fixing the preset positions of the prefabricated anti-collision guardrails 6 on the prefabricated bridge decks 5 through locking pieces after accurate positioning of embedded pieces.

The invention aims to overcome the defects in the prior art, further improve the assembly degree of a conventional span bridge, improve the integration, adaptability and integrity of assembled bridge components, and provide an assembled steel-concrete combined structure bridge suitable for mountain environments and a construction method; an assembled bridge structure which integrates a steel pipe concrete pier system, a combined pier top beam and a reinforced concrete composite beam as main components; the invention solves the problems of low assembly degree of the bridge under the existing mountain condition, overcomes the problems of poor overall stress performance, low material utilization efficiency, high field assembly operation difficulty, difficult control of components and assembly quality, low industrialized construction degree, poor landscape performance, high maintenance difficulty and the like of the conventional assembled bridge, has the advantages of reasonable structural stress, full play of material performance, convenient transportation and installation of prefabricated components, convenient and quick field construction, strong applicability to complex mountain environments, small influence on ecological environments, economic manufacturing cost and attractive appearance, has higher economic and social values, and is a novel assembled bridge structure worthy of popularization and use; the structure and the material use efficiency are improved, and the processing and the manufacturing, the member transportation and the field assembly are convenient.

Meanwhile, the scheme also has the following characteristic points:

(1) The assembled steel-concrete combined structure bridge suitable for mountain land environment comprises steel pipe concrete pier columns 2, combined pier top cross beams 3, steel main beams 4 and prefabricated bridge deck 5 assembly modules, the component standardization degree is high, the processing and the transportation are easy, the site construction operation is simple, and the quality and the efficiency are improved;

the invention is characterized in that the divided assembly type components (prefabricated pier column steel shell, steel main beam, box beam, bridge deck and the like) are matched in size and weight, have lighter weight, can be constructed by using a small crane of the same model, and reduce the requirements on construction equipment; the prefabricated pier column steel shell and the box girder can be directly used as templates for concrete pouring, so that the difficulty of concrete pouring is reduced; the assembly nodes corresponding to the pier bottom and the pier top have low requirements on installation errors and fineness, have larger redundancy and are convenient for field installation;

(2) The steel-concrete combined structure reduces the constant load self weight of the bridge at one stage, improves the material utilization efficiency, and is beneficial to exerting the application effects of high-strength steel and ultra-high-performance concrete materials;

(3) The steel pipe concrete pier column 2 adopts a double-column steel pipe concrete pier system, the section size is smaller, the space occupation of the lower structure of the bridge can be effectively saved, and the earth excavation amount is reduced; the steel pipe concrete pier columns 2 can be vertically grouped according to the pier height requirement, so that standardized manufacturing and production are facilitated, and the transportation and hoisting difficulties are reduced; the middle part of the double-column pier is provided with a transverse connection, so that the transverse rigidity of the bridge is improved;

(4) The pier beam connection adopts a full-fixedly-connected system, so that on one hand, the torsion constraint on the beam ends of the multi-ribbed steel main beam 4 beams is improved, the number of transverse connections between the steel main beams 4 is reduced, the field operation difficulty is reduced, and the system has strong adaptability to the conditions of small-radius flat curves and large-longitudinal slopes; on the other hand, the travelling comfort and smoothness are good, the replacement of a support and an expansion joint in the later period is avoided, the management and maintenance are easy in the operation period, and the overall durability of the structure is improved;

(4) The main beam adopts a multi-ribbed rigid-concrete combined structure, the stress advantages of steel and concrete structures are exerted, and the steel main beam 4 and the concrete bridge deck can adopt standardized size components, so that the processing and the hoisting are convenient; the multi-ribbed steel girder transverse connection adopts a few-beam system, so that the workload of site construction connection operation is reduced;

(6) The auxiliary modules can be assembled, the anti-collision guardrails, the drainage grooves, the connecting keys and the like can be produced in a batch customized manner, the defect of cracking and scattering of traditional auxiliary facilities is avoided, standardized and rapid installation and use are facilitated, and rapid installation and later maintenance of bridge auxiliary facilities are facilitated;

(7) Fully assembled steel-concrete structure bridge; compared with the traditional concrete structure, the girder has the advantages of lower girder height, smaller bridge pier size and occupied space, relatively blanking of the bridge girder connecting structure, relatively coordinated overall proportion scale of the bridge, remarkable integral landscape quality improving effect, integration level of auxiliary facilities, good bridge deck flatness and relatively good using function.

Finally, it is noted that the above embodiments are only for illustrating the technical solution of the present invention and not for limiting the same, and although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications and equivalents may be made thereto without departing from the spirit and scope of the technical solution of the present invention, which is intended to be covered by the scope of the claims of the present invention.

Claims (10)

1. The utility model provides an assembled steel-mixed composite structure bridge suitable for mountain region environment which characterized in that: the combined pier comprises a foundation, a steel tube concrete pier column, a combined pier top beam, a steel girder and a prefabricated bridge deck; the steel pipe concrete pier column comprises a prefabricated pier column steel shell and concrete poured in the prefabricated pier column steel shell; the combined pier top beam comprises a box beam with a prefabricated steel structure and concrete poured in the box beam; the foundation is fixed at a preset position, the bottom end of the prefabricated pier column steel shell is fixed on the foundation, the prefabricated pier column steel shell is welded and fixed with the box girder, the steel girder is welded and fixed with the box girder, and the end part of the steel main girder and the top end of the prefabricated pier column steel shell are poured in the box girder together; the steel girder and the box girder are mutually perpendicular, the top surface of the steel girder and the top surface of the box girder are located on the same horizontal plane, the top surface of the steel girder and the top surface of the box girder which are located on the same horizontal plane form a supporting surface, the prefabricated bridge deck boards are paved on the supporting surface, the prefabricated bridge deck boards are arranged in a plurality of blocks, and the prefabricated bridge deck boards are arranged along the extending direction of the bridge body.

2. The fabricated steel-concrete composite structural bridge suitable for use in a mountain environment as claimed in claim 1, wherein: the box girder is internally provided with a reinforcing rib plate which is arranged close to the steel girder, and the reinforcing rib plate and the box girder are prefabricated at the same time; the reinforcing rib plate comprises a reinforcing transverse rib and a reinforcing longitudinal rib, the transverse ends of the reinforcing transverse rib respectively and correspondingly extend to a box beam transverse end plate which is transversely close to the reinforcing transverse rib, the longitudinal ends of the reinforcing longitudinal rib respectively and correspondingly extend to a box beam longitudinal end plate which is longitudinally close to the reinforcing longitudinal rib, the reinforcing transverse rib is provided with a transverse rib through hole, and the reinforcing longitudinal rib is provided with a longitudinal rib through hole, so that a box of the box beam is divided into a plurality of mutually communicated reinforcing chambers by the reinforcing transverse rib and the reinforcing longitudinal rib.

3. The fabricated steel-concrete composite structural bridge suitable for use in a mountain environment as claimed in claim 1, wherein: the steel tube concrete pier columns are uniformly distributed at the bottom of the box girder along the transverse direction;

the steel pipe concrete pier column is characterized by further comprising inter-column transverse connecting beams, wherein the inter-column transverse connecting beams are prefabricated steel structural members, and two steel pipe concrete pier columns which are transversely adjacent are connected by the inter-column transverse connecting beams to form a pier column coupling group.

4. The fabricated steel-concrete composite structural bridge suitable for use in a mountain environment as claimed in claim 1, wherein: the concrete filled steel tube pier column limiting groove for assembling the concrete filled steel tube pier column is reserved on the foundation, and the concrete filled steel tube pier column is fixed to the foundation through the concrete filled steel tube pier column limiting groove.

5. The fabricated steel-concrete composite structural bridge suitable for use in a mountain environment as claimed in claim 1, wherein: the steel pipe concrete pier column further comprises a steel bar cage fixed at the bottom end of the prefabricated pier column steel shell, a plurality of reinforcing ribs are arranged at the connecting interface of the steel bar cage and the prefabricated pier column steel shell, and the reinforcing ribs are uniformly distributed in the circumferential direction of the connecting interface of the steel bar cage and the prefabricated pier column steel shell; and prefabricating the reinforcement cage, the reinforcing ribs and the prefabricated pier column steel shells.

6. The fabricated steel-concrete composite structural bridge suitable for use in a mountain environment as claimed in claim 1, wherein: the anti-collision guardrail is assembled on the prefabricated bridge deck through a connecting assembly;

the connecting assembly comprises an embedded part and a locking part, wherein the embedded part is embedded in the prefabricated anti-collision guardrail, the embedded part is provided with a connecting end extending out of the prefabricated anti-collision guardrail, and the locking part is assembled on the connecting end and used for fixing the prefabricated anti-collision guardrail on the prefabricated bridge deck.

7. The fabricated steel-concrete composite structural bridge suitable for use in a mountain environment as claimed in claim 6, wherein: the bottom surface of the prefabricated crash barrier has a longitudinally extending keyway, and the top surface of the prefabricated deck has a longitudinally extending key that mates with the keyway.

8. The fabricated steel-concrete composite structural bridge suitable for use in a mountain environment as claimed in claim 1, wherein: the top surface of the steel girder is provided with a shear pin group, the prefabricated bridge deck is provided with a notch for accommodating the shear pin group, and the steel girder and the prefabricated bridge deck form a whole through the fixation of the shear pin group in the notch;

the shear force nail crowd is prefabricated simultaneously with the steel girder, the notch is reserved when prefabricated decking is prefabricated.

9. The fabricated steel-concrete composite structural bridge suitable for use in a mountain environment as claimed in claim 8, wherein: the shear force nail group comprises a plurality of shear force nails distributed on the top surface of the steel girder at set positions, the root parts of the shear force nails are fixed on the steel girder, and the head parts of the shear force nails are positioned in the notch and fixed on the prefabricated bridge deck;

the shear force nail group is a plurality of groups, the notch is a plurality of, the quantity of the shear force nail group is the same with that of the notch, and the shear force nail group is connected with the notch in a one-to-one correspondence.

10. A construction method of an assembled steel-concrete composite structure bridge applicable to mountain environments based on any one of claims 1-9, which is characterized in that: the construction method comprises the following construction steps:

s1, constructing a foundation, wherein a steel pipe concrete pier column limiting groove for assembling a steel pipe concrete pier column is reserved at the top of the foundation;

s2, constructing a concrete filled steel tube pier column, and integrating the concrete filled steel tube pier column and a foundation;

the construction of the concrete filled steel tube pier column comprises the following steps:

s2a, pouring concrete at the bottom end of the steel pipe concrete pier column, and enabling the bottom end of a prefabricated pier column steel shell with a reinforcement cage and a plurality of reinforcing ribs to be limited in a steel pipe concrete pier column limiting groove so that the bottom end of the steel pipe concrete pier column and a foundation are poured to form a whole;

the bottom ends of two concrete filled steel tube pier columns in the pier column coupling group are respectively and correspondingly poured into the same limiting groove, so that the pier column coupling group is supported by the same foundation;

pouring concrete at the bottom end of the steel pipe concrete pier column, and enabling the top of the foundation to form a protection section wrapping the connection interface of the reinforcement cage and the prefabricated pier column steel shell, wherein the protection section protrudes out of the top surface of the foundation;

before pouring concrete at the bottom end of the steel pipe concrete pier column, erecting a template for defining the shape of the protection section on the top of the foundation;

S2, pouring concrete positioned at the upper part of the bottom end of the steel pipe concrete pier column in a prefabricated pier column steel shell, wherein a post-pouring section with a preset depth is reserved at the top end of the prefabricated pier column steel shell;

the height of the steel pipe concrete pier column is increased through superposition of prefabricated pier column steel shells;

when the prefabricated pier column steel shells are overlapped, clamping plates are arranged in the circumferential direction of the connecting interfaces of the adjacent prefabricated pier column steel shells, so that central axes of the prefabricated pier column steel shells spliced up and down are approximately overlapped, and the adjacent prefabricated pier column steel shells form a whole in a welding mode;

removing the clamping plates after the adjacent prefabricated pier stud steel shells are integrated;

s3, constructing a combined pier top beam and a steel girder, and integrating the combined pier top beam, the steel girder and a steel pipe concrete pier column;

before the combined pier top cross beam and the steel main beam are constructed, fixing the adjacent prefabricated pier column steel shells in the pier column coupling group through the inter-column transverse connecting beams of the prefabricated steel structure;

the construction of the combined pier top cross beam and the steel main beam comprises the following steps:

s3a, welding and fixing the box girder on the top end of the steel pipe concrete pier stud, enabling the box of the box girder to be communicated with the post-pouring section, wherein the top end of the prefabricated pier stud steel shell is positioned in the box of the box girder;

s3b, welding and fixing the steel main beam on the box beam, wherein the end part of the steel main beam is positioned in the box of the box beam;

S3c, pouring concrete in the box girder, and filling concrete in the box of the box girder and the post-pouring section of the steel pipe concrete pier, so that the steel pipe concrete pier, the steel girder and the box girder with the reinforced rib plates form a whole of a steel-concrete structure;

s4, constructing a prefabricated bridge deck, and integrating the prefabricated bridge deck, the combined pier top cross beam and the steel main beam;

the prefabricated bridge deck construction includes:

s4a, paving a prefabricated bridge deck supported by the steel girder and the combined pier top cross beam on the supporting surface, and limiting the prefabricated bridge deck by a shear nail group on the top surface of the steel girder through a notch;

s4b, pouring concrete in the notch, filling the concrete in the notch so that the shear nail group of the steel girder is fixedly connected in the notch of the prefabricated bridge deck through the concrete, and thus the prefabricated bridge deck and the steel girder form a whole;

s5, assembling the prefabricated anti-collision guardrail at the set position of the prefabricated bridge deck.