CN209989692U

CN209989692U - Combined box girder

Info

Publication number: CN209989692U
Application number: CN201920530943.3U
Authority: CN
Inventors: 陈宜言; 代亮; 何晓晖; 王梦雨; 于芳; 夏少华; 王小花; 王程伟
Original assignee: Shenzhen Municipal Design and Research Institute Co Ltd
Current assignee: Shenzhen Municipal Design and Research Institute Co Ltd
Priority date: 2019-04-18
Filing date: 2019-04-18
Publication date: 2020-01-24
Anticipated expiration: 2029-04-18

Abstract

The utility model relates to a combination case roof beam, include: a top plate; a support web, a first end of which is connected with the top plate; the connecting web plate comprises a first connecting part and a second connecting part connected with the first connecting part, the first connecting part is connected with the second end of the supporting web plate, and the width of the cross section of the second connecting part is smaller than that of the cross section of the first connecting part; and a bottom plate connected with the second connection part. The combined box girder can effectively reduce the dead weight of the box girder, optimize the stress of the structure and solve the problem that the bottom plate is easy to crack.

Description

Combined box girder

Technical Field

The utility model relates to a bridge engineering technical field especially relates to combination box girder.

Background

In the prior art, the combined box girder has the advantages of good earthquake resistance, high prestress efficiency, convenient construction and the like, and the bridge girder of the type is rapidly developed due to the advantages of excellent structural performance, reasonable comprehensive construction cost and the like.

However, the lower edge of the existing combined box girder is of a reinforced concrete structure and is hung at the bottom of the girder, so that the concrete has poor tensile property and is easy to crack, and the increase of the span of the bridge is influenced due to the larger dead weight of the concrete structure.

SUMMERY OF THE UTILITY MODEL

Based on this, it is necessary to provide a combination box girder which can effectively reduce the dead weight of the box girder, optimize the structural stress and solve the problem that the bottom plate is easy to crack, aiming at the problems that the dead weight of the existing combination box girder is larger and easy to crack.

A composite box girder comprising:

a top plate;

a support web, a first end of which is connected with the top plate;

the connecting web plate comprises a first connecting part and a second connecting part connected with the first connecting part, the first connecting part is connected with the second end of the supporting web plate, and the width of the cross section of the second connecting part is smaller than that of the cross section of the first connecting part; and

and the bottom plate is connected with the second connecting part.

Above-mentioned combination case roof beam is connected bottom plate and support web through connecting the web, has effectively alleviateed the dead weight of combination case roof beam, and tensile strength is excellent, can optimize the structure atress and solve the bottom plate fracture problem. In addition, the connecting area of the first connecting part of the connecting web plate and the supporting web plate is large, the connecting area of the second connecting part of the connecting web plate and the bottom plate is small, the area with large positive stress of the bottom plate can be effectively avoided, and the structural fatigue strength is improved. The connecting web plate can bear shearing force and participate in bending in the length direction of the combined box girder, so that the section rigidity of the combined box girder is improved, the stress level of the bottom plate is reduced, and the span of the bridge is increased.

In one embodiment, the top plate comprises a steel reinforcement framework structure, a template and the steel reinforcement framework structure are arranged in a penetrating mode through a fastener device, and concrete is poured to form the top plate. The structure of the top plate formed by pouring is more stable.

In one embodiment, the steel bar framework structure comprises at least two elongated main steel bars and a plurality of annular stirrups, the stirrups are sleeved on the two main steel bars at intervals, and the two main steel bars are oppositely abutted against the inner side walls of the stirrups. The steel bar framework has the advantages of simple structure, easy operation, capability of adopting an assembly type construction process, reduction of the workload of field operation, easy control of construction quality and high construction precision.

In one embodiment, four main steel bars are provided, the stirrups are square, and the four main steel bars are correspondingly abutted against the inner side walls of the four corners of the stirrups. Can make the framework of steel reinforcement structure more stable.

In one embodiment, the support web is an accordion steel web. The folded steel web has a fold effect, so that the combined box girder has better anti-seismic performance, higher prestress efficiency and more convenient construction.

In one embodiment, the folded steel web comprises a plurality of first unit plates and a plurality of second unit plates, the first unit plates protrude towards the outer side of the combined box girder along the width direction of the combined box girder, the second unit plates protrude towards the middle of the combined box girder along the width direction of the combined box girder, and two second unit plates are respectively connected to two opposite ends of one first unit plate.

In one embodiment, the wind turbine further comprises an upper flange plate, and the upper flange plate is respectively connected with the top plate and the first end of the supporting web. By means of the upper flange plate, the strength of the connection between the top plate and the support web can be increased.

In one embodiment, the joint of the upper flange plate and the support web is provided with a plurality of deformation openings at intervals along the length direction of the combined box girder. The deformation port can reduce the rigidity of the upper flange plate along the length direction of the combined box girder, improve the prestress efficiency, save materials, simultaneously coordinate the deformation coordination capacity between the top plate and the supporting web plate, and reduce the secondary internal force generated by temperature and concrete shrinkage creep.

In one embodiment, the upper flange plate is provided with a plurality of fractures at intervals along the length direction of the combined box girder, the first end of the supporting web plate is provided with an arc opening at a position corresponding to the fractures, and the fractures are communicated with the arc opening to form the deformation opening.

In one embodiment, the combined box girder further comprises a plurality of stiffening ribs which are arranged on one side of the bottom plate facing the supporting web at intervals along the width direction of the combined box girder. The stability of the bottom plate structure can be enhanced by the arrangement of the stiffening ribs.

Drawings

Fig. 1 is a schematic structural view of an embodiment of the composite box girder of the present invention;

FIG. 2 is a schematic structural view of another embodiment of the composite box girder of the present invention;

FIG. 3 is a schematic structural view of a first embodiment of a deformation port in the composite box girder shown in FIG. 2;

FIG. 4 is a schematic structural view of a second embodiment of a deformation port in the composite box girder shown in FIG. 2;

FIG. 5 is a schematic structural view of a third embodiment of a deformation port in the composite box girder shown in FIG. 2;

FIG. 6 is a schematic structural view of an embodiment of the top deck of the composite box girder of FIG. 2;

FIG. 7 is a cross-sectional structural view of a first embodiment of a support web in the composite box girder of FIG. 2;

FIG. 8 is a cross-sectional structural view of a second embodiment of a support web in the composite box girder of FIG. 2;

FIG. 9 is a cross-sectional structural view of a third embodiment of a support web in the composite box girder of FIG. 2;

fig. 10 is a cross-sectional structural view of a fourth embodiment of a support web in the composite box girder of fig. 2.

In the drawings, the components represented by the respective reference numerals are listed below:

1. a top plate; 11. a main reinforcing bar; 12. hooping; 13. a pre-stressed structure; 2. a support web; 21. a first unit plate; 22. a second unit plate; 23. an arc opening; 3. connecting the webs; 31. a first connection portion; 32. a second connecting portion; 4. a base plate; 41. a stiffening rib; 5. a fastener device; 51. a first baffle plate; 52. a second baffle; 53. a support bar; 6. a template; 7. an upper flange plate; 71. breaking off; 8. and (4) deforming the opening.

Detailed Description

In order to make the above objects, features and advantages of the present invention more comprehensible, embodiments of the present invention are described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. The present invention can be embodied in many different forms other than those specifically described herein, and it will be apparent to those skilled in the art that similar modifications can be made without departing from the spirit and scope of the invention, and it is therefore not to be limited to the specific embodiments disclosed below.

It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only and do not represent the only embodiments.

Unless defined otherwise, 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 invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

Referring to fig. 1, in an embodiment, the assembled box girder includes: top plate 1, support web 2, connecting web 3 and bottom plate 4. The top of supporting web 2 is connected with the bottom of roof 1, and the top of connecting web 3 is connected with the bottom of supporting web 2, and the bottom of connecting web 3 is connected with bottom plate 4. The connecting area of the connecting web 3 and the supporting web 2 is larger than the connecting area of the connecting web 3 and the bottom plate 4. Through connecting web 3 with bottom plate 4 and support web 2 be connected, effectively alleviateed the dead weight of combination box beam, and tensile strength is excellent, can optimize the structure atress and solve the bottom plate fracture problem. In addition, the connecting area of the connecting web plate 3 and the supporting web plate 2 is large, the connecting area of the connecting web plate 3 and the bottom plate 4 is small, the area with large normal stress of the bottom plate 4 can be effectively avoided, and the structural fatigue strength is improved. The connecting web 3 can bear shearing force and participate in bending in the length direction of the combined box girder, so that the section rigidity of the combined box girder is improved, the stress level of the bottom plate 4 is reduced, and the span of the bridge is increased.

In practical application, bottom plate 4 can be the steel bottom plate, and the structure atress of steel bottom plate is better, and joint strength preferred can be with more stable, firm installation of combination case roof beam through the steel bottom plate. Compared with the existing combined box girder, the weight can be reduced by 15-25%. In order to enhance the structural stability of the bottom plate 4, a plurality of stiffening ribs 41 are further provided on the steel bottom plate. Specifically, a plurality of stiffening ribs 41 are provided on the steel bottom plate at intervals in the width direction of the composite box girder, and are located on the top surface of the steel bottom plate.

Referring to fig. 6, in one embodiment, the top plate 1 is a reinforced concrete top plate and includes a steel skeleton structure, and the steel skeleton structure can be used as a load-bearing structure during construction and as a permanent structure to form the top plate 1 together with concrete to bear load. In a particular application, the fastener means 5 and the template 6 are required. The fastener device 5 includes a first baffle 51, a second baffle 52 and a support rod 53. The template 6 is placed at the bottom. The steel bar framework structure is provided with a plurality of steel bar framework structures, the steel bar framework structures are arranged above the template 6 side by side, and the steel bar framework structures extend along the length direction of the template 6. Template 6 and steel reinforcement framework structure are worn to establish by bracing piece 53, and first baffle 51 is connected with bracing piece 53's one end to with 6 butts of template, second baffle 52 is connected with bracing piece 53's the other end, and with steel reinforcement framework structure butt, form fixed frame after fastener device 5 locks is fixed, then to pouring concrete in the frame in order to form roof 1. The top plate 1 formed by casting has more stable structure.

Specifically, the steel bar skeleton structure includes four main steel bars 11 and a plurality of square stirrups 12. Four main reinforcing bars 11 are located to the 12 spaced cover of a plurality of stirrups, and four main reinforcing bars 11 correspond the inside wall butt location with four angles of stirrup 12. The steel bar framework has the advantages of simple structure, easy operation, capability of adopting an assembly type construction process, reduction of the workload of field operation, easy control of construction quality and high construction precision. The diameter of the main steel bar 11 can be 14-28 mm, the diameter of the stirrups 12 can be 8-16 mm, the distance between each stirrup 12 is 10-20 cm, and the distance between adjacent steel bar framework structures is 30-50 cm.

Referring to fig. 1 and 2, a prestressed structure 13 is further disposed in the reinforced concrete top plate according to the structural stress requirement, so as to prevent the reinforced concrete top plate from cracking.

It should be noted that only two main reinforcements 11 may be provided, and the stirrups 12 may be annular. Two main reinforcing bars 11 all with the inside wall butt of stirrup 12, and two main reinforcing bar 11's position is relative, form stable skeleton texture. Stirrup 12 can also be triangle-shaped, and main reinforcing bar 11 corresponds can set up three, and three main reinforcing bar 11 correspond with the inside wall butt location of the three angles of stirrup 12. The number of the main reinforcements 11 and the shape of the stirrup 12 are not limited as long as the main reinforcements 11 can be positioned in contact with the inner side wall of the stirrup 12.

Referring to fig. 2, in one embodiment, the support web 2 is a steel web. The folded steel web plate comprises a plurality of first unit plates 21 and a plurality of second unit plates 22, and two second unit plates 22 are respectively connected to two opposite ends of one first unit plate 21. In the width direction of the composite box girder, the first unit plate 21 protrudes outward of the composite box girder, and the second unit plate 22 protrudes toward the middle of the composite box girder. The folded steel web has a fold effect, so that the combined box girder has better anti-seismic performance, higher prestress efficiency and more convenient construction. Referring to fig. 7, in the first embodiment, the cross-sectional shapes of the first unit plate 21 and the second unit plate 22 may be arched; referring to fig. 8, in the second embodiment, the cross-sectional shapes of the first unit plate 21 and the second unit plate 22 may be polygonal; referring to fig. 9, in the third embodiment, the cross-sectional shapes of the first unit plate 21 and the second unit plate 22 may be circular arc shapes; referring to fig. 10, in the second embodiment, the cross-sectional shapes of the first unit plate 21 and the second unit plate 22 may be triangular.

Referring to fig. 1, in one embodiment, the connection web 3 includes a first connection portion 31 and a second connection portion 32 connected to the first connection portion 31. The first connecting portion 31 is connected with the bottom end of the support web 2, the second connecting portion 32 is connected with the bottom plate 4, and the cross-sectional width of the second connecting portion 32 is smaller than that of the first connecting portion 31. It will be appreciated that the connecting web 3 may be a steel web having a generally T-shaped cross section, with the transverse plates of wider cross section being the first connecting portions 31 and the risers of narrower cross section being the second connecting portions 32. The height of the T-shaped steel web plate can be 20 cm-50 cm, or the range below the neutral axis can be taken according to the section characteristic of the combined bellows. The T-shaped steel web plate is welded between the folded steel web plate and the steel bottom plate.

The composite box girder also comprises an upper flange plate 7. The upper flange plate 7 is respectively connected with the top plate 1 and the supporting web plate 2. By providing the upper flange plate 7, the strength of the connection between the top plate 1 and the support web 2 can be increased.

Referring to fig. 2, in an embodiment, a plurality of deformation openings 8 are formed at the connection position of the upper flange plate 7 and the folded steel web plate at intervals along the length direction of the combined box girder. The deformation opening 8 can reduce the rigidity of the upper flange plate 7 in the length direction of the combined box girder, simultaneously avoid stress concentration, improve the internal prestress efficiency of the top plate 1, coordinate the deformation adaptability of the top plate 1 and the folded steel web plate, and reduce the secondary internal force generated by temperature and shrinkage creep of the top plate 1. The spacing between the deformation openings 8 can generally be determined by an integer multiple of the wavelength of the web of deformed steel or by calculation. Specifically, the upper flange plate 7 is provided with a plurality of fractures 71 at intervals along the length direction of the combined box girder, the positions of the folded steel web corresponding to the fractures 71 are provided with the arc openings 23, and the fractures 71 are communicated with the arc openings 23 to form the deformation openings 8. The width of the fracture 71 may be 2cm to 3 cm. The arc opening 23 can be round, oval or square, and when the arc opening 23 is round or oval, the radius can be 5 cm-10 cm. Referring to fig. 3, in the first embodiment, the break 71 is spliced with the arc-shaped opening 23 to form a mushroom-shaped deformation opening 8; referring to fig. 4, in the second embodiment, the fracture 71 and the square arc opening 23 are spliced to form a square deformation opening 8; referring to fig. 5, in the third embodiment, the fracture 71 and the circular arc 23 are spliced to form the circular deformation opening 8.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only represent some embodiments of the present invention, and the description thereof is specific and detailed, but not to be construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several variations and modifications can be made, which are within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims

1. A composite box girder, comprising:

a top plate;

a support web, a first end of which is connected with the top plate;

and the bottom plate is connected with the second connecting part.

2. The composite box girder of claim 1, wherein the top plate comprises a steel skeleton structure, a formwork and the steel skeleton structure are penetrated through by a fastener device, and concrete is poured to form the top plate.

3. The assembled box girder according to claim 2, wherein the steel reinforcement cage structure comprises at least two elongated main steel reinforcements and a plurality of annular stirrups, the stirrups are alternately sleeved on the two main steel reinforcements, and the two main steel reinforcements are oppositely abutted against the inner side walls of the stirrups.

4. The assembled box girder according to claim 3, wherein four main reinforcing bars are provided, the stirrups are square, and the four main reinforcing bars are correspondingly abutted against the inner side walls of the four corners of the stirrups.

5. The composite box girder according to claim 1, wherein the support webs are steel folded webs.

6. The composite box girder according to claim 5, wherein the folded steel webs comprise a plurality of first unit plates and a plurality of second unit plates, the first unit plates protrude to the outer side of the composite box girder in the width direction of the composite box girder, the second unit plates protrude to the middle of the composite box girder in the width direction of the composite box girder, and two second unit plates are connected to opposite ends of one first unit plate, respectively.

7. The composite box beam defined in claim 1 further comprising an upper flange plate connected to the top plate and the first end of the support web, respectively.

8. The composite box girder according to claim 7, wherein the connection between the upper flange plate and the support web is provided with a plurality of deformation ports at intervals along the length direction of the composite box girder.

9. The composite box girder according to claim 8, wherein the upper flange plate is provided with a plurality of fractures at intervals along the length direction of the composite box girder, the first end of the supporting web is provided with an arc opening at a position corresponding to the fractures, and the fractures are communicated with the arc opening to form the deformation opening.

10. The composite box girder according to any one of claims 1 to 9, further comprising a plurality of stiffening ribs provided on a side of the bottom plate facing the support web at intervals in a width direction of the composite box girder.