Cavity assembly type reinforced concrete web bridge structure and construction method thereof

Abstract

The invention discloses a cavity assembly type reinforced concrete web bridge structure and a construction method thereof, and relates to the technical field of bridge engineering.The cavity assembly type reinforced concrete web bridge structure comprises a plurality of cavity type webs arranged in the length direction of a bridge, the upper side and the lower side of the web center component are each provided with a steel bar staggered net composed of a plurality of oblique steel bars and a plurality of transverse steel bar rings, and the steel bar staggered nets are in a hollow frustum shape. The top flange steel plate is horizontally arranged at the top of the cavity type web, and a concrete bridge deck is arranged at the top of the top flange steel plate; the lower flange steel plate is horizontally arranged at the bottom of the cavity type web; according to the hollow cavity type web, the inclined steel bars, the transverse steel bar rings and the web center component are combined to form a hollow frustum structure, the dead weight of a web bridge structure is greatly reduced, stress concentration is avoided, the cracking risk of the structure is reduced, and the overall strength and stability of the structure are effectively enhanced; meanwhile, local shear resistance and bending resistance are enhanced, the service life of the bridge is prolonged, and the probability of local damage is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of bridge engineering, in particular to a cavity assembly type steel-concrete web bridge structure and a construction method thereof. BACKGROUND

[0002] The web bridge is a bridge structure with a web as the main load-bearing member, and its core feature is to use vertical or oblique webs to bear loads and form a whole force system through the top plate and the bottom plate. The web bridge usually adopts a steel structure, a concrete structure or a steel-concrete composite structure, and has various types such as T-shaped web bridge, I-shaped web bridge, box-shaped web bridge and rectangular web bridge according to the cross-sectional form, as shown in the drawing, which is suitable for small and medium span bridges and has the advantages of lightweight, high stiffness and convenient construction. Figures 1-3

[0003] The traditional web bridge is mostly a solid web bridge, and the web thereof is a continuous and non-perforated solid structure of concrete or steel, which has strong shear resistance, but as the engineering application increases, it also exposes obvious defects, including:

[0004] (1) The structure has a large self-weight, resulting in a large foundation engineering burden, high material and construction costs, and the large self-weight also leads to a larger structural inertia force under the action of an earthquake, which is prone to be damaged by the earthquake force;

[0005] (2) The internal stress distribution of the solid web bridge is uneven, and under the action of loads (such as vehicle driving and temperature change), stress concentration is prone to occur in local areas (such as the connection between the web and the top plate / bottom plate), which may cause concrete cracking, steel corrosion, reduction of structural strength and stability, and frequent maintenance, thereby increasing the long-term maintenance cost;

[0006] (3) The solid web formwork structure is complex, especially for thick webs, and the manufacturing, installation and disassembly take a long time, the steel bar binding and concrete pouring space are limited, the construction difficulty is large, and the construction period is prone to be prolonged;

[0007] (4) The assembled solid web has a large weight, and the transportation needs to rely on large equipment, thereby increasing the transportation cost. SUMMARY

[0008] In view of one or more deficiencies of the prior art, the present application provides a cavity assembly type steel-concrete web bridge structure and a construction method thereof, which can effectively reduce the self-weight of the bridge, optimize the stress distribution, thereby improving the seismic performance and construction efficiency, and greatly reducing the cost; meanwhile, in terms of stress, the degree of prestress loss can be reduced, and the shear resistance of the bridge can be improved.

[0009] In order to achieve the above-mentioned purpose, one or more technical solutions are adopted in the present application as follows:

[0010] ​In a first aspect, a cavity assembled steel-concrete web bridge structure is provided, comprising:

[0011] a plurality of cavity webs arranged along the length direction of the bridge, each comprising a web center member, an upper side and a lower side of the web center member being arranged with a steel bar staggered net, the steel bar staggered net comprising a plurality of oblique steel bars, a transverse steel bar ring, and high-strength concrete wrapping the oblique steel bars and the transverse steel bar ring, the steel bar staggered net being in a hollow frustum shape;

[0012] an upper flange steel plate horizontally arranged on the top of the cavity web, a concrete bridge deck being arranged on the top of the upper flange steel plate;

[0013] a lower flange steel plate horizontally arranged on the bottom of the cavity web.

[0014] As a further implementation manner, the plurality of oblique steel bars form a hollow frustum structure, the transverse steel bar ring is arranged on the outer side of the oblique steel bars, and / or the transverse steel bar ring is arranged on the inner side of the oblique steel bars.

[0015] As a further implementation manner, the plurality of transverse steel bar rings are uniformly arranged along the longitudinal direction of the oblique steel bars, so as to avoid stress concentration and improve the overall strength of the cavity web.

[0016] As a further implementation manner, the transverse steel bar ring is welded to the oblique steel bar.

[0017] As a further implementation manner, one end of the oblique steel bar is fixedly connected to the web center member, and the other end is fixedly connected to the upper flange steel plate or the lower flange steel plate.

[0018] As a further implementation manner, the oblique steel bar is fixedly connected to the web center member through concrete pouring, and the oblique steel bar is welded to the upper flange steel plate or the lower flange steel plate.

[0019] As a further implementation manner, the upper end and the lower end of the web center member are respectively provided with a plurality of web oblique holes, the lower end of the upper flange steel plate is provided with a plurality of top plate oblique holes, and the upper end of the lower flange steel plate is provided with a plurality of bottom plate oblique holes; one end of the oblique steel bar on the upper side of the web center member is inserted into the web oblique hole, and the other end is inserted into the top plate oblique hole; one end of the oblique steel bar on the lower side of the web center member is inserted into the bottom plate oblique hole.

[0020] As a further implementation manner, a plurality of rivets are uniformly arranged on the upper side of the upper flange steel plate, the rivets are vertically arranged in the upper flange steel plate and welded to the upper flange steel plate, so as to further enhance the connection strength and the stability of the bridge structure.

[0021] As a further implementation manner, the lower flange steel plate is vertically provided with a plurality of stiffening ribs which are welded to the lower flange steel plate; the stiffening ribs are uniformly arranged between two adjacent cavity webs to improve structural rigidity and enhance bearing capacity and stability.

[0022] As a further implementation manner, the cross-sectional shape of the web oblique hole, the top plate oblique hole and the bottom plate oblique hole is circular or square, and the diameter is greater than the diameter of the oblique steel bar.

[0023] As a further implementation manner, the upper side and the upper side of the web center component are symmetrically arranged with the steel bar staggered net.

[0024] As a further implementation manner, the high-strength concrete is UHPC ultra-high performance concrete.

[0025] In another aspect, a construction method of the cavity assembly type steel-concrete web bridge structure is provided, and the method comprises the following steps:

[0026] The concrete is poured on the prefabricated component on site to form the web center component;

[0027] The oblique steel bars are respectively installed in the web oblique holes reserved at the upper end and the lower end of the web center component, and secondary pouring is performed to fixedly connect the web center component and the oblique steel bars;

[0028] The transverse steel bar rings are respectively installed on the upper side and the lower side of the web center component, and secondary reinforcement is performed by using a steel bar binding gun, high-strength concrete is poured to form a hollow frustum-shaped steel bar staggered net, and the cavity web is obtained;

[0029] The oblique steel bars on the upper side of the web center component are inserted into the top plate oblique hole, and the oblique steel bars on the lower side are inserted into the bottom plate oblique hole, and are welded and fixed;

[0030] The concrete bridge deck is formed by pouring on the top of the upper flange steel plate.

[0031] As a further implementation manner, the secondary poured concrete needs to be vibrated and compacted to ensure that the concrete is fully combined with the existing components.

[0032] By adopting the technical scheme, the application has the following beneficial effects:

[0033] 1. The cavity type web of the present application greatly reduces the self weight of the web bridge structure, avoids stress concentration, reduces the risk of cracking of the structure, and effectively enhances the overall strength and stability of the structure by forming a hollow frustum structure design through the combination of inclined steel bars, transverse steel bar rings and web center components.

[0034] 2. Compared with the traditional solid web bridge structure, the cavity type web of the present application significantly reduces the amount of concrete used, optimizes the arrangement of steel bars, improves the utilization efficiency of materials and the construction efficiency of the bridge structure, greatly reduces the cost, and is economical.

[0035] 3. The appearance of the traditional solid web structure is usually regular rectangular or trapezoidal, with low environmental integration; the hollow cavity type web in the present application is designed as a hollow frustum structure, which is light in structure and can be designed as a circular or other shape, improving the aesthetics of the bridge and better integrating into the environment, with significant advantages in areas such as business centers and tourist attractions that require high aesthetics.

[0036] 4. The cavity assembly type steel-concrete web bridge structure of the present application has reduced self weight, and the cavity type web is less affected by seismic forces in earthquakes, and the cavity structure can absorb seismic energy, improving the seismic performance.

[0037] 5. The formwork of the cavity type web of the present application is simple to make, and the prefabrication process is convenient for steel bar binding and concrete pouring, which is beneficial to shorten the construction period and reduce the engineering cost.

[0038] 6. The cavity type web of the present application is light in weight and the volume is also optimized, significantly reducing the transportation difficulty and improving the transportation efficiency; at the same time, the cavity structure can also absorb vibration impact, reducing the risk of transportation damage. BRIEF DESCRIPTION OF DRAWINGS

[0039] The drawings accompanying the specification of the present application form a part thereof, serve to provide further understanding of the present application, and together with the description of the exemplary embodiments of the present application and their description serve to explain the present application, and do not constitute an improper limitation of the present application.

[0040] Figure 1 is a schematic diagram of the T-shaped web bridge structure in the prior art;

[0041] Figure 2 is a schematic diagram of the I-shaped web bridge structure in the prior art;

[0042] Figure 3 is a side sectional view of the box-shaped web bridge structure in the prior art;

[0043] Figure 4 Front view of cavity assembled steel-concrete web bridge structure of the embodiment of the present application;

[0044] Figure 5 Side view of cavity assembled steel-concrete web bridge structure of the embodiment of the present application;

[0045] Figure 6 Front view of cavity web of cavity assembled steel-concrete web bridge structure of the embodiment of the present application;

[0046] Figure 7 Plan view of web central component of cavity assembled steel-concrete web bridge structure of the embodiment of the present application;

[0047] Figure 8 Figure 4 Local enlarged view of part I;

[0048] Figure 9 Figure 4 Local enlarged view of part II.

[0049] In the figure: 100, cavity web; 200, upper flange steel plate; 300, lower flange steel plate; 400, concrete bridge deck; 500, rivet; 600, stiffening rib;

[0050] 101, web central component; 102, oblique steel bar; 103, transverse steel bar ring; 104, high-strength concrete. DETAILED DESCRIPTION

[0051] It should be noted that the following detailed description is illustrative only and is intended to provide further description of the present application. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0052] It is to be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments consistent with the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and / or "comprising," when used in this specification, specify the presence of stated features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0053] Embodiment One

[0054] In a typical embodiment of the present application, a cavity assembled steel-concrete web bridge structure is provided, as shown in​​Figure 4-9 As shown in the drawings, comprising:

[0055] A plurality of cavity webs 100 arranged along the longitudinal and / or transverse direction of the bridge, including a web center member 101, the upper and lower sides of the web center member 101 are arranged with a steel bar staggered net, which includes a plurality of inclined steel bars 102, a transverse steel ring 103 and high-strength concrete 104 wrapping the inclined steel bars and the transverse steel ring, the steel bar staggered net is in the shape of a hollow truncated cone;

[0056] An upper flange steel plate 200 is horizontally arranged on the top of the cavity web 100, and a concrete bridge deck 400 is arranged on the top of the upper flange steel plate 200;

[0057] A lower flange steel plate 300 is horizontally arranged on the bottom of the cavity web 100.

[0058] Specifically, as shown in Figure 4 and Figure 5 The cavity fabricated steel-concrete web bridge structure of the embodiment forms a whole force system with the cavity web 100, the upper flange steel plate 200 and the lower flange steel plate 300, wherein the cavity web 100 is mainly composed of the web center member 101, the transverse steel ring 103 and the inclined steel bars 102, and forms a steel-concrete collaborative force system through a fabricated splicing manner to bear shear force and local bending moment and transmit the load to the support; the upper flange steel plate 200 is horizontally arranged on the top of the cavity web, the concrete bridge deck 400 above the upper flange steel plate is cast with UHPC ultra-high performance concrete, and the concrete bridge deck 400 directly bears the vehicle load; the lower flange steel plate 300 is horizontally arranged on the bottom of the cavity web 100 to provide a tensile / compressive area and form a closed force ring with the cavity web 100 and the upper flange steel plate 200.

[0059] Further, as shown in Figure 4 and Figure 5 Two rows of cavity webs 100 are arranged along the transverse direction of the bridge, and each row is uniformly arranged with a plurality of cavity webs 100 along the longitudinal direction of the bridge, and each cavity web 100 is fixedly connected with the upper flange steel plate 200 and the lower flange steel plate 300 to form a steel-concrete composite web bridge.

[0060] Specifically, as shown in Figure 6 The cavity web 100 is composed of the web center member 101 and the steel bar staggered net on the upper and lower sides of the web center member 101, the web center member 101 is formed by a post-pouring UHPC ultra-high performance concrete process, the steel bar staggered net is arranged in the shape of a hollow truncated cone on the upper and lower sides of the web center member, and a cavity is formed on the inner side of the steel bar staggered net, so that the self-weight of the whole cavity web is greatly reduced, which is beneficial to reduce the material cost, optimize the stress distribution and improve the seismic performance of the whole bridge structure.

[0061] Further, to optimize the steel bar distribution, the steel bar part of the steel bar staggered net is arranged by the oblique steel bars 102 and the transverse steel bar ring 103, and meanwhile, the high-strength concrete 104 is poured on the oblique steel bars 102 and the transverse steel bar ring 103, the high-strength concrete 104 wraps the oblique steel bars 102 and the transverse steel bar ring 103, so that the steel bar staggered net forms a stable reinforced concrete structure, and the steel bar staggered net as a whole is in a hollow frustum shape and has an internal cavity. In the embodiment, to further enhance the overall performance of the cavity-type web, the high-strength concrete is UHPC ultra-high performance concrete, and in other embodiments, other concrete materials with high compressive strength, high toughness and high durability can also be used. As shown in Figure 4 、 Figure 8 and Figure 9 , the UHPC ultra-high performance concrete fully wraps the transverse steel bar ring 103 and the oblique steel bars 102, ensures the close combination of the steel bars and the concrete, and improves the shear resistance, bearing capacity and stability of the cavity-type web steel-concrete collaborative force system.

[0062] Further, as shown in Figures 6-9 , the top and bottom of the web central member are provided with a plurality of web oblique holes, and the web oblique holes are uniformly distributed in a circular manner. The bottom of the upper flange steel plate is provided with a plurality of top plate oblique holes distributed in a circular manner, and the top of the lower flange steel plate is provided with a plurality of bottom plate oblique holes distributed in a circular manner. The cross-sectional shape of the web oblique hole, the top plate oblique hole and the bottom plate oblique hole is circular or square. As shown in Figures 6-9 , in the embodiment, the cross-sectional shape is circular, the diameter of the top plate oblique hole, the bottom plate oblique hole and the web oblique hole is the same, and is slightly larger than the diameter of the oblique steel bar. In addition, the number of the top plate oblique hole, the bottom plate oblique hole and the web oblique hole is consistent, the interval between adjacent top plate oblique holes and the interval between adjacent bottom plate oblique holes are both larger than the interval between adjacent web oblique holes on the web central member, that is, the diameter of the circle formed by the distribution of the top plate oblique hole and the bottom plate oblique hole is larger than the diameter of the circle formed by the distribution of the web oblique hole, therefore, the oblique steel bars 102 on the upper side and the lower side of the web central member 101 are arranged in a hollow frustum shape, and in the preferred embodiment of the application, the steel bar staggered net on the upper side and the lower side of the web central member 101 is symmetrically arranged, forming two upper and lower symmetric hollow frustum structures, and the cavity-type web has two cavities, which greatly reduces the self-weight of the web structure and reduces the amount of concrete.

[0063] Further, for the arrangement of the oblique steel bars, on the upside of the web central member 101, the bottom of the oblique steel bar 102 is inserted into the web oblique hole, and the permanent fixed connection between the oblique steel bar 102 and the web central member 101 is realized by secondary concrete pouring, and the top of the oblique steel bar 102 is inserted into the top plate oblique hole, and the oblique steel bar 102 is fixedly connected with the upper flange steel plate 200 by welding. Among them, the secondary poured concrete needs to be vibrated and compacted to ensure that the concrete is fully combined with the existing components and improve the stability of the connection. On the downside of the web central member 101, the top of the oblique steel bar 102 is inserted into the web oblique hole, and the oblique steel bar 102 is fixedly connected with the web central member 101 by secondary concrete pouring, and the bottom of the oblique steel bar 102 is inserted into the bottom plate oblique hole, and the bottom of the oblique steel bar 102 is welded with the lower flange steel plate 300.

[0064] Further, for the arrangement of the transverse steel bar ring, in combination with Figure 6 and Figure 7 It is shown that the transverse steel bar ring 103 is arranged in several rows in the height direction of the hollow web, and the several transverse steel bar rings 103 are uniformly distributed along the longitudinal direction of the oblique steel bar. In this embodiment, as shown in Figures 7-9 , the plurality of transverse steel bar rings 103 are arranged alternately on the inner side and the outer side of the oblique steel bar 102, and each transverse steel bar ring 103 is arranged horizontally and fixedly connected with the several oblique steel bars 102 distributed in a circle. Of course, in other embodiments, all the transverse steel bar rings can be arranged on the inner side of the oblique steel bar, or all the transverse steel bar rings can be arranged on the outer side of the oblique steel bar, or arranged in other forms on the inner side and the outer side of the oblique steel bar, and the present application does not limit the comparison.

[0065] Among them, each transverse steel bar ring 103 is welded with all the contacting oblique steel bars 102 to form a transversely and horizontally distributed steel bar staggered net, and the transversely and horizontally staggered net after welding and fixing can be reinforced again by a steel bar binding gun, so as to improve the bending and shearing resistance of the hollow web, and enhance the strength and stability of the hollow assembly type steel-concrete web bridge structure.

[0066] In this embodiment, the design of the steel bar staggered net is subject to the requirement of structural stress, and the specifications, spacing and arrangement of the oblique steel bar and the transverse steel bar net can be determined through detailed calculation.

[0067] In other alternative embodiments, the web central member can not be provided with a preset web oblique hole, and a whole prefabricated steel cage can be used as an alternative structure of the steel bar staggered net, in combination with the poured concrete, to obtain a steel-concrete cooperatively stressed hollow web.

[0068] Specifically, to further enhance the connection strength and the stability of the bridge structure, in the embodiment, rivets 500 are arranged on the upper flange steel plate 200 according to design requirements. As shown in Figure 4 and Figure 8 , the upper flange steel plate 200 is uniformly provided with a plurality of rivets 500 arranged on the upper side, and the rivets 500 are vertically arranged in the upper flange steel plate 200 and are welded and fixed to the upper flange steel plate 200, further enhancing the connection strength and the stability of the bridge structure. It should be noted that in the preferred construction process, after the oblique steel bars are inserted into the upper flange steel plate and the rivets are fixed on the upper flange steel plate, the UHPC super high performance concrete is poured to obtain the concrete bridge deck.

[0069] Specifically, to further enhance the load bearing capacity and stability of the bridge structure, a plurality of stiffening ribs 600 are vertically arranged on the upper side of the lower flange steel plate 300, as shown in Figure 4 , the plurality of stiffening ribs 600 are uniformly arranged between the adjacent two hollow web plates to improve the structural rigidity. In the embodiment, the stiffening ribs 600 are fixed to the lower flange steel plate 300 by welding. The specifications, spacing and other parameters of the stiffening ribs need to be determined through detailed structural calculation to ensure that they can effectively enhance the overall performance of the structure.

[0070] In a specific embodiment, taking a bridge with a span of 20 meters as an example, the construction data of a traditional solid web bridge structure is compared with the hollow assembly type steel-concrete bridge structure of the present application, and the following results are obtained:

[0071] The dead load of the traditional solid single-piece small box girder structure is about 57.7 tons, while the dead load of the hollow assembly type steel-concrete bridge structure of the present embodiment is reduced to about 50 tons, which is reduced by about 13.8%. After reducing the self-weight, the pressure on the foundation of the bridge is reduced, and the complexity and cost of the foundation engineering are reduced. At the same time, the reduction of the self-weight also reduces the long-term constant load borne by the structure, prolonging the service life of the bridge.

[0072] The amount of steel reinforcement per cubic meter of concrete of the traditional solid web structure is about 4.61 cubic meters / ton, while the hollow web of the present application adopts a hollow frustum structure, which optimizes the arrangement of steel reinforcement, reduces the amount of steel reinforcement per cubic meter of concrete to about 6.01 cubic meters / ton, significantly reduces the material cost, and thus directly reduces the construction cost, while reducing the maintenance cost in the later period, improving the economy of the bridge.

[0073] In the present application, the hollow web adopts a hollow frustum structure, the formwork is simple to make, the precast process is convenient for steel reinforcement binding and concrete pouring, and the construction difficulty is reduced. Therefore, in actual construction, the construction period of the bridge structure of the present embodiment is about 0.8 times that of the traditional solid web bridge structure, improving the construction efficiency, reducing the labor cost and management cost, and having less impact on traffic guidance and the surrounding environment.

[0074] The solid web structure has obvious stress concentration phenomenon under the action of load, especially at the connection between the web and the upper flange steel plate / lower flange steel plate, and the embodiment effectively disperses the stress by reasonably arranging the oblique steel bars and the transverse steel bar ring, thereby avoiding stress concentration. Under the same load condition, the stress concentration coefficient of the bridge structure of the embodiment is about 0.85 times that of the traditional solid web bridge structure, the stress distribution is optimized, the crack resistance of the bridge structure is significantly improved, the risk of concrete cracking is greatly reduced, the possibility of steel corrosion is reduced, and the overall strength and stability of the structure are enhanced.

[0075] The oblique transverse distribution of the steel bar staggered net surface formed by the combination of the oblique steel bars and the transverse steel bar ring in the embodiment can better transmit the bending moment to the web center component under the action of shear force, and the transverse steel bar ring can resist the bending moment when bending, thereby not only enhancing the local shear capacity and bending resistance, but also improving the integrity of the structure. Under the same load condition, the shear capacity of the bridge structure of the embodiment is about 1.2 times that of the traditional solid web bridge structure, and the shear capacity is about 1.3 times that of the traditional solid web bridge structure, so that the structure of the bridge is more stable under the action of vehicle load and temperature change, and the cracks and damage caused by shear force are reduced. Under the same load condition, the local damage probability of the traditional solid web bridge structure is about 15%, and the local damage probability of the bridge structure of the embodiment can be reduced to about 5%, thereby reducing the risk of local damage, prolonging the service life of the bridge, and reducing the long-term maintenance cost.

[0076] Embodiment two

[0077] In another typical embodiment of the present application, a construction method of a cavity assembly type steel-concrete web bridge structure is also provided, which is based on the cavity assembly type steel-concrete web bridge structure in embodiment one and specifically includes the following steps:

[0078] UHPC (ultra-high performance concrete) is poured on the prefabricated component on site to form the web center component;

[0079] The oblique steel bars are respectively installed in the oblique holes reserved at the upper end and the lower end of the web center component, and secondary pouring is performed to fixedly connect the web center component and the oblique steel bars;

[0080] The transverse steel bar ring is respectively installed on the upper side and the lower side of the web center component, and secondary reinforcement is performed by using a steel bar binding gun to form an oblique transverse distribution of a steel bar staggered net, thereby obtaining a cavity type web;

[0081] The oblique steel bars on the upper side of the web center component are inserted into the oblique holes in the top plate, and the oblique steel bars on the lower side are inserted into the oblique holes in the bottom plate, and are welded and fixed;

[0082] UHPC ultra-high performance concrete is cast on top of the top flange steel plate to form the bridge deck.

[0083] Specifically, the web center member needs to be accurately reserved with oblique holes at its upper and lower ends during the manufacturing process. The size, position and shape of these holes are required to be consistent with the above-mentioned reserved holes, so as to be inserted with oblique steel bars subsequently. The web center member is formed by using the post-cast UHPC ultra-high performance concrete process. After the concrete is cast and reaches a certain strength, the oblique steel bars are inserted into the oblique holes reserved at the upper and lower ends of the web center member, and then the UHPC ultra-high performance concrete is cast again to realize the permanent fixed connection of the web center member and the oblique steel bars. The cast concrete needs to be vibrated and compacted to ensure the full combination with the existing member.

[0084] After the above connection is completed, the formation of the hollow web is carried out:

[0085] The transverse steel bar ring and the oblique steel bars are surrounded inside the formwork, and then the UHPC ultra-high performance concrete is cast. During the casting process, vibration or other auxiliary means can be used to make the UHPC ultra-high performance concrete fully wrap the transverse steel bar ring and the oblique steel bars, so as to ensure the close combination of the steel bars and the concrete, and finally form the hollow web structure of the steel-concrete collaborative force system. The design and installation of the formwork should meet the requirements of concrete casting to ensure the accuracy of the structural size.

[0086] The hollow web is connected with the lower flange steel plate and the upper flange steel plate respectively:

[0087] The oblique holes for the bottom plate are accurately reserved on the lower flange steel plate according to the design requirements. The size and position of these holes are accurately designed according to the insertion requirements of the oblique steel bars, and the shape is usually circular or square, and the diameter or side length should be slightly larger than the diameter of the oblique steel bars. During construction, the oblique steel bars at the lower end of the hollow web are inserted into the reserved holes, and after preliminary positioning, the welding process is used for connection to realize the permanent fixed connection of the lower flange steel plate and the hollow web structure. At the same time, in order to meet the requirements of structural stiffness, bearing capacity and stability, the stiffening ribs are uniformly arranged on the lower flange steel plate. The specifications, spacing and other parameters of the stiffening ribs are determined through detailed structural calculation to ensure that they can effectively enhance the overall performance of the structure.

[0088] The oblique holes for the top plate are also accurately reserved on the upper flange steel plate, and the size, position and shape requirements are consistent with the oblique holes for the bottom plate on the lower flange steel plate. The oblique steel bars at the upper end of the hollow web are permanently fixed and connected with the upper flange steel plate by welding.

[0089] In addition, rivets are nailed on the upper flange steel plate according to design requirements. When the top plate is constructed, the steel bar staggered net is first installed as a steel bar framework, and then UHPC super high performance concrete is poured to form a concrete bridge deck. In the pouring process, the concrete is ensured to be fully combined with the rivets and the upper flange steel plate, so that the upper flange steel plate and the hollow web are stably connected. In order to ensure that the design of the steel bar staggered net meets the structural stress requirements, the specifications, spacings and arrangement modes of the inclined steel bars and the horizontal steel bar net are determined through detailed calculation.

[0090] It should be noted that the above examples are only used to illustrate the technical solutions of the present application, but not to limit it, and those of ordinary skill in the art should understand that the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A cavity assembled steel-concrete web bridge structure, characterized in that: include: Several hollow webs arranged along the length of the bridge include a web core member, with steel meshes arranged on the upper and lower sides of the web core member, respectively. The steel meshes include several diagonal steel bars, transverse steel rings, and high-strength concrete surrounding the diagonal steel bars and the transverse steel rings. The steel meshes are in the shape of a hollow cone. An upper flange steel plate is horizontally arranged on top of the cavity-type web, and a concrete bridge deck is arranged on top of the upper flange steel plate; The lower flange steel plate is horizontally arranged at the bottom of the cavity type web.

2. The cavity assembled steel-concrete web bridge structure according to claim 1, characterized in that: The plurality of oblique steel bars are arranged to form a hollow frustum structure, the transverse steel bar ring is arranged on the outside of the oblique steel bars, and / or the transverse steel bar ring is arranged on the inside of the oblique steel bars.

3. The cavity assembled steel-concrete web bridge structure according to claim 1, characterized in that: The plurality of transverse reinforcement rings are evenly arranged along the longitudinal direction of the oblique reinforcement; the transverse reinforcement rings are welded to the oblique reinforcement.

4. The cavity assembled steel-concrete web bridge structure according to claim 1, characterized in that: One end of the oblique steel bar is fixedly connected to the web center member, and the other end is fixedly connected to the upper flange steel plate or the lower flange steel plate.

5. The cavity assembled steel-concrete web bridge structure according to claim 4, characterized in that: The upper and lower ends of the web center member are respectively pre-set with a number of web oblique holes, the lower end of the upper flange steel plate is provided with a number of top plate oblique holes, and the upper end of the lower flange steel plate is provided with a number of bottom plate oblique holes; one end of the oblique steel bar on the upper side of the web center member is inserted into the web oblique hole, and the other end is inserted into the top plate oblique hole; one end of the oblique steel bar on the lower side of the web center member is inserted into the bottom plate oblique hole.

6. The cavity assembled steel-concrete web bridge structure according to claim 1, characterized in that: A plurality of rivets are evenly arranged on the upper side of the upper flange steel plate. The rivets are vertically arranged and welded to the upper flange steel plate.

7. The cavity assembled steel-concrete web bridge structure according to claim 1, characterized in that: A plurality of stiffening ribs are vertically arranged on the upper side of the lower flange steel plate, and the stiffening ribs are welded to the lower flange steel plate.

8. The cavity assembled steel-concrete web bridge structure according to claim 1, characterized in that: A plurality of stiffening ribs are vertically provided on the upper side of the lower flange steel plate, and the stiffening ribs are welded to the lower flange steel plate; the plurality of stiffening ribs are evenly arranged between two adjacent cavity webs.

9. The cavity assembled steel-concrete web bridge structure according to claim 1, characterized in that: The high-strength concrete adopts UHPC ultra-high performance concrete.

10. A construction method for a cavity assembled steel-concrete web bridge structure according to any one of claims 1 to 9, characterized in that: The steps include: Concrete the precast components on site to form the web center member; Install oblique steel bars in the oblique holes reserved at the upper and lower ends of the web center member, and perform secondary pouring to securely connect the web center member and the oblique steel bars. Transverse steel rings are installed on the upper and lower sides of the central member of the web, and secondary reinforcement is performed using a steel bar tying gun. High-strength concrete is poured to form a hollow cone-shaped steel bar interlaced network to obtain a cavity web. Insert the oblique steel bars on the upper side of the web center member into the oblique holes in the top plate, and insert the oblique steel bars on the lower side into the oblique holes in the bottom plate, and weld them in place. The concrete bridge deck is cast on top of the upper flange steel plate.

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