CN216891925U - Wave form steel web combination case girder construction based on arch structure atress - Google Patents
Wave form steel web combination case girder construction based on arch structure atress Download PDFInfo
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- CN216891925U CN216891925U CN202220243196.7U CN202220243196U CN216891925U CN 216891925 U CN216891925 U CN 216891925U CN 202220243196 U CN202220243196 U CN 202220243196U CN 216891925 U CN216891925 U CN 216891925U
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Abstract
The utility model provides a corrugated steel web plate combined box girder structure based on stress of an arch structure, which comprises a plurality of piers, wherein pier top cross beams are arranged on the piers, adjacent pier top cross beams are connected through an arched concrete bottom plate, the concrete bottom plate comprises a plurality of precast concrete plates which are sequentially connected, the precast concrete plates are connected in series through prestressed steel hinge lines, and the prestressed steel hinge lines penetrate through steel hinge line channels to extend out and are fixed on the corresponding pier top cross beams. According to the utility model, the prefabricated concrete plates are connected by the pull belts and are integrally hoisted to the pier top cross beam, the construction of the one-span arched concrete bottom plate can be completed by one-time hoisting, a large number of complex temporary supporting devices are not needed, the construction process is simpler and more convenient, the construction cost is saved, and the application prospect is good.
Description
Technical Field
The utility model relates to a corrugated steel web plate combined box girder structure based on arch structure stress.
Background
The height of the corrugated steel web plate combined box girder bridge is higher at the fulcrum and lower at the midspan position, and the height is changed from the fulcrum to the midspan according to a certain change form, so that the bottom plate of the main girder is changed generally according to a certain linear shape. For the construction of a concrete bottom plate which is changed in a certain linear shape, a hanging basket construction or a support cast-in-situ construction is generally adopted. Hang basket construction or support cast-in-place all need carry out the formwork, and the formwork degree of difficulty greatly increased has not only influenced the whole engineering progress, still can assemble the problem because of the template and cause the concrete bottom plate to pour the back appear leaking thick liquid and leak quality problems such as muscle. Meanwhile, unreasonable vibration is easy to occur during concrete pouring, large air bubbles cannot be completely discharged, and the outer surface of the concrete bottom plate can cause honeycomb pitted surfaces, so that the attractiveness of the bridge is influenced, and the use requirement of design cannot be met. The construction method of the support cast-in-place is influenced by construction environment and cannot be applied to bridges with larger spans.
A large amount of temporary facilities such as special supports are needed in the construction process of the arch structure bridge, so that the construction process is complicated, the construction cost is increased, and the project progress is influenced.
Disclosure of Invention
In view of this, the utility model aims to provide a corrugated steel web combined box girder structure based on arch structure stress and a construction method, and solves the problems in the technical scheme.
The utility model is realized by adopting the following scheme: the utility model provides a wave form steel web combination box girder structure based on arch structure atress, includes a plurality of piers, installs the pier top crossbeam on the pier, connects through arched concrete bottom plate between the adjacent pier top crossbeam, concrete bottom plate includes a plurality of precast concrete plates that connect gradually, and through prestressing force steel strand polyphone between each precast concrete plate, the steel strand passageway that runs through of prestressing force steel strand stretches out and is fixed in on the pier top crossbeam that corresponds.
Furthermore, a plurality of prestressed holes penetrating through the precast concrete slabs along the bridge direction are formed in the precast concrete slabs, the prestressed holes in the adjacent precast concrete slabs correspond to one another one to one, the corresponding prestressed holes are mutually connected to form a steel strand channel, the prestressed steel strands are arranged in the steel strand channel, two ends of each prestressed steel strand penetrate through the steel strand channel and extend out and are anchored on the corresponding pier top cross beam, and cement mortar is poured into the gaps between the prestressed holes and the prestressed steel strands.
Furthermore, at least one drawstring is installed on the concrete bottom plate, and each concrete bottom plate is detachably connected with the drawstring.
Further, the lower surface of the precast concrete plate along the bridge direction is longer than the upper surface.
Furthermore, a concrete shear key is arranged between the joints of the adjacent precast concrete plates, the concrete shear key can adopt a trapezoidal or rounded trapezoid cross section, and the height of the concrete shear key is more than 2 times of the maximum aggregate particle size of the concrete and less than 35 mm; the ratio of the height of the concrete shear key to the average width thereof was taken to be 1: 2.
Furthermore, the connecting end, corresponding to the precast concrete bottom plate, on the lateral part of the pier top cross beam is provided with an inclined boundary plane, the inclined boundary plane is perpendicular to the axis of the precast concrete bottom plate, and the two sides of the cross beam are provided with anchoring points corresponding to the prestressed steel strands.
Furthermore, the precast concrete plate is of a reinforced concrete structure, the left side and the right side of the precast concrete plate are both pre-embedded with corrugated steel webs with a certain height, and the distance between the bottom surface of the pier top beam and the lowest point of the precast concrete bottom plate is not less than 0.5 m.
Further, precast concrete plate includes the precast concrete bottom plate side by side that connects gradually about a plurality of, and adjacent precast concrete bottom plate side by side passes through the prestressing force hinge line and connects around, forms concrete bottom plate rib side by side, controls adjacent concrete bottom plate rib side by side and connects through horizontal prestressing force or wet seam between the rib to connect gradually along the horizontal bridge, the pre-buried wave form steel web in the outside of the concrete bottom plate rib side by side of both sides.
Compared with the prior art, the utility model has the following beneficial effects: through adopting the stretching strap to connect precast concrete plate and carry out integral hoisting to pier top crossbeam, can accomplish the construction of one-span arch concrete bottom plate and need not a large amount of complicated interim strutting arrangement through once hoist and mount, construction process is more simple and convenient, saves engineering cost, has fine application prospect.
Drawings
Fig. 1 is a schematic view of a concrete slab block structure of the present invention;
FIG. 2 is a schematic view of the structure of a drawstring-connected concrete slab block before hoisting according to the present invention;
FIG. 3 is a schematic diagram of a concrete slab structure during hoisting according to the present invention;
fig. 4 is a schematic view of the completed hoisted concrete slab block structure of the present invention;
FIG. 5 is a schematic view of the structure of the pier top beam of the present invention;
FIG. 6 is a schematic structural diagram of the utility model after installation of a corrugated steel web;
FIG. 7 is a schematic structural view of the finished roof panel of the present invention;
FIG. 8 is a schematic view of a rib structure of a concrete bottom plate at one side of a hoisting device in embodiment 2 of the present invention;
FIG. 9 is a top view of a concrete floor rib on one side of a hoisting frame in embodiment 2 of the present invention;
FIG. 10 is a schematic view of a rib structure for hoisting a middle concrete floor in embodiment 2 of the present invention;
FIG. 11 is a top view of ribs of a middle concrete floor hoisted in the embodiment 2 of the present invention;
fig. 12 is a schematic structural view of a concrete floor completed by hoisting in embodiment 2 of the present invention.
In the figure: 1-a concrete floor; 2-pre-burying a corrugated steel web plate; 3-concrete top plate; 4-prestressed holes; 5-pulling the belt; 6-a pier top beam; 7-concrete shear key; 8-inclined interface plane; 9-corrugated steel web; 10-side by side concrete floor ribs.
Detailed Description
The utility model is further explained below with reference to the drawings and the embodiments.
It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure. 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 application belongs.
It is 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 according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.
As shown in fig. 1-7, this embodiment provides a wave form steel web combination box girder structure based on arch structure atress, including a plurality of piers (not shown), install pier top crossbeam 6 on the pier, connect through arched concrete bottom plate 1 between the adjacent pier top crossbeam, concrete bottom plate includes a plurality of precast concrete plates that connect gradually, and each precast concrete plate is established ties through prestressing steel hinge line (not shown) between each, and the steel hinge line passageway that runs through of prestressing steel hinge line stretches out and is fixed in on the pier top crossbeam that corresponds.
In this embodiment, a plurality of prestressed holes 4 penetrating through the precast concrete slabs along the bridge direction are formed in the precast concrete slabs, the prestressed holes on the adjacent precast concrete slabs correspond to one another one to one, the corresponding prestressed holes are connected with one another to form a steel strand channel, the prestressed steel strands are arranged in the steel strand channel, two ends of each prestressed steel strand penetrate through the steel strand channel and extend out and are anchored on the corresponding pier top cross beam, and cement mortar is poured into the gaps between the prestressed holes and the prestressed steel strands.
In this embodiment, install at least one stretching strap 5 on the concrete bottom plate, releasable connection between each concrete bottom plate and the stretching strap, this device adopts three stretching straps, and the stretching strap can rotate to can demolish.
In this embodiment, for reasonable design, the two side surfaces of the precast concrete slab along the bridge have a certain inclination, that is, the length of the lower surface of the precast concrete slab along the bridge is greater than that of the upper surface.
In this embodiment, a concrete shear key 7 is arranged between the joints of the adjacent precast concrete plates, the concrete shear key can adopt a trapezoidal or rounded trapezoidal section, and the height of the concrete shear key is more than 2 times of the maximum aggregate particle size of the concrete and less than 35 mm; the ratio of the height of the concrete shear key to the average width thereof was taken to be 1: 2.
In this embodiment, the connection end of the pier top cross beam corresponding to the precast concrete bottom plate is provided with an inclined boundary plane 8, the inclined boundary plane is perpendicular to the axis of the precast concrete bottom plate, the two sides of the cross beam are provided with anchoring points corresponding to the prestressed steel strands, the ends of the prestressed steel strands are anchored on the anchoring points, and the distance between the bottom surface of the pier top cross beam and the lowest point of the precast concrete bottom plate is not less than 0.5 m.
In this embodiment, the precast concrete plate is of a reinforced concrete structure, and the left and right sides of the precast concrete plate are both pre-embedded with corrugated steel webs 2 of a certain height.
In this embodiment, wave form steel web 9 is welded on pre-buried wave form steel web 2 upper portion, and the regional top that encloses between adjacent pier top crossbeam top and the wave form steel web of corresponding both sides is sealed through concrete roof 3.
Example 2: referring to fig. 8-12, since it is difficult to directly hoist the whole concrete floor, the concrete floor is prefabricated in half-width or block form, the prefabricated concrete plates are connected by drawstrings according to different prefabrication modes of the concrete floor, the concrete floor is divided into side-by-side concrete floor ribs, and the concrete floor ribs are hoisted in sequence from one side until the construction of the concrete floor is completed. The rest is the same as in example 1. The combined box girder bridge is suitable for a combined box girder bridge with a wider concrete bottom plate, reduces the hoisting difficulty, and adopts the following specific technical scheme: in this embodiment, precast concrete plate includes about a plurality of in proper order the prefabricated side by side concrete floor that docks, and the adjacent (in the same direction as the bridge promptly) prefabricated side by side concrete floor passes through the prestressing force hinge line and connects around, forms side by side concrete floor rib 10, and adjacent (in the same direction as the cross bridge promptly) side by side concrete floor rib docks along the cross bridge in proper order about, the pre-buried wave form steel web in the outside of the side by side concrete floor rib of both sides. A construction method of a corrugated steel web combined box girder structure based on arch structure stress comprises the following steps:
step 1: and (3) constructing a bridge lower part structure: binding reinforcing steel bars of the bridge pier and the bridge abutment, pouring bridge pier and bridge abutment concrete, and maintaining;
step 2: prefabricating concrete bottom plate blocks: assembling templates according to the size of the divided concrete bottom plates, binding prefabricated concrete plate reinforcing steel bars, embedding a prestressed pipeline and a part of highly corrugated steel web plates, pouring concrete, and maintaining;
and step 3: and (3) pier top beam construction: using the pier as a support, installing a pier top beam support and a template, binding reinforcing steel bars, installing a prestressed pipeline, pouring concrete, and maintaining;
and 4, step 4: and (3) concrete bottom plate construction: transporting the precast concrete bottom plate blocks to the positions near the bridge site, sequentially installing the precast concrete bottom plate blocks on the construction platform through positioning, attaching the drawstrings to the top surfaces of the precast concrete bottom plate blocks and connecting the drawstrings, integrally hoisting the precast concrete bottom plate blocks by using a crane to form an arch, and installing the arched concrete bottom plate blocks on a pier top beam;
and 5: and (3) prestress construction: inserting prestressed steel strands into the concrete bottom plate, and tensioning the prestressed steel strands to finish anchor sealing;
step 6: construction of the corrugated steel web: welding and connecting the corrugated steel web plate with a corrugated steel web plate pre-embedded in a concrete bottom plate;
and 7: and (3) concrete top plate construction: taking the corrugated steel web plate and the concrete bottom plate as supports, erecting a template on the corrugated steel web plate, and pouring a concrete top plate;
and 8: bridge deck pavement and auxiliary engineering construction.
In this embodiment, in step 3, when the support is supported on the pier, the support needs to be installed first, the temporary consolidation measure is adopted to consolidate the pier top beam and the pier, and after the construction of the main structure of the bridge is completed, the temporary consolidation measure is removed, and the upper structure of the bridge is supported by the support. In step 4, the concrete bottom plates are installed in a transverse bridge direction in a blocking mode, the concrete bottom plates are composed of concrete bottom plate ribs arranged side by side, and the concrete bottom plate ribs are connected through transverse prestress or wet joints.
According to the utility model, the corrugated steel web composite beam bridge arch bottom plate is prefabricated in sections, the precast concrete bottom plate blocks are sequentially installed on the construction platform through positioning, the drawstrings are attached to the top surfaces of the precast concrete bottom plate blocks and connected, the crane is used for hoisting the concrete bottom plate blocks integrally, and the arched concrete bottom plate is installed on the pier top cross beam, so that the erection efficiency of the corrugated steel web composite box beam bridge arch concrete bottom plate can be effectively improved, the assembly quality of the concrete bottom plate blocks is ensured, the construction process is simpler and more convenient, the construction cost is saved, and the application prospect is good.
Any embodiment disclosed herein above is meant to disclose, unless otherwise indicated, all numerical ranges disclosed as being preferred, and any person skilled in the art would understand that: the preferred ranges are merely those values which are obvious or representative of the technical effect which can be achieved. Since the numerical values are too numerous to be exhaustive, some of the numerical values are disclosed in the present invention to illustrate the technical solutions of the present invention, and the above-mentioned numerical values should not be construed as limiting the scope of the present invention.
If the terms "first," "second," etc. are used herein to define parts, those skilled in the art will recognize that: the terms "first" and "second" are used merely to distinguish one element from another in a descriptive sense and are not intended to have a special meaning unless otherwise stated.
If the utility model discloses or relates to parts or structures which are fixedly connected to each other, the fixedly connected parts can be understood as follows, unless otherwise stated: a detachable fixed connection (for example using bolts or screws) is also understood as: non-detachable fixed connections (e.g. riveting, welding), but of course, fixed connections to each other may also be replaced by one-piece structures (e.g. manufactured integrally using a casting process) (unless it is obviously impossible to use an integral forming process).
In addition, the orientations or positional relationships indicated for indicating the positional relationships such as "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like, applied in any of the technical aspects of the present disclosure described above are based on the orientations or positional relationships shown in the drawings and are only for convenience of describing the present disclosure, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be construed as limiting the present disclosure, and the terms used for indicating the shapes applied in any of the technical aspects of the present disclosure described above are meant to include shapes similar, analogous or approximate thereto unless otherwise stated.
Any part provided by the utility model can be assembled by a plurality of independent components or can be manufactured by an integral forming process.
Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present invention and not to limit the same; although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art will understand that: modifications to the specific embodiments of the utility model or equivalent substitutions for parts of the technical features may be made; without departing from the spirit of the present invention, it is intended to cover all aspects of the utility model as defined by the appended claims.
Claims (8)
1. The utility model provides a wave form steel web combination box girder structure based on arch structure atress, includes a plurality of piers, installs the pier top crossbeam on the pier, connects through arched concrete bottom plate between the adjacent pier top crossbeam, a serial communication port, concrete bottom plate includes a plurality of precast concrete plates that connect gradually, through prestressing force hinge line polyphone between each precast concrete plate, on the steel hinge line passageway that runs through of prestressing force hinge line stretched out and was fixed in corresponding pier top crossbeam.
2. The corrugated steel web combination box girder structure based on arch structure stress as claimed in claim 1, wherein the precast concrete slabs are provided with a plurality of prestressed holes penetrating through the precast concrete slabs in the bridge direction, the prestressed holes of adjacent precast concrete slabs are in one-to-one correspondence, each corresponding prestressed hole is connected with each other to form a steel strand channel, the prestressed steel strand is arranged in the steel strand channel, both ends of the prestressed steel strand extend through the steel strand channel and are anchored on the corresponding pier top beams, and cement mortar is poured into the prestressed hole and the prestressed steel strand gap.
3. The arched structure stress-based corrugated steel web composite box girder structure of claim 2, wherein at least one drawstring is installed on the concrete bottom plate, and each concrete bottom plate is detachably connected with the drawstring.
4. An arch stress based corrugated steel web composite box girder structure according to claim 3, wherein the lower surface of the precast concrete slab in the bridge direction is longer than the upper surface.
5. The corrugated steel web combination box girder structure based on arch structure stress as claimed in claim 4, wherein a concrete shear key is arranged between the joints of the adjacent precast concrete plates, the concrete shear key can adopt a trapezoidal or rounded trapezoid cross section, and the height of the concrete shear key is more than 2 times of the maximum aggregate grain size of the concrete and less than 35 mm; the ratio of the height of the concrete shear key to the average width thereof was taken to be 1: 2.
6. The arched structure stress-based corrugated steel web combination box girder structure according to claim 5, wherein the connection ends of the pier top beam side parts corresponding to the precast concrete bottom plates are provided with inclined boundary planes perpendicular to the precast concrete bottom plate axis, and the beam side parts are provided with anchoring points corresponding to the prestressed steel strands.
7. The arched structure stress-based corrugated steel web combined box girder structure of claim 6, wherein the precast concrete slab is of a reinforced concrete structure, the corrugated steel webs with a certain height are pre-embedded in the left side and the right side of the precast concrete slab, and the distance between the bottom surface of the pier top beam and the lowest point of the precast concrete bottom plate is not less than 0.5 m.
8. The corrugated steel web combination box girder structure based on arch structure stress of claim 7, wherein the precast concrete slabs comprise a plurality of precast side-by-side concrete bottom plates which are sequentially connected from left to right, the precast side-by-side concrete bottom plates which are adjacent from front to back are connected through a prestressed steel hinge line to form side-by-side concrete bottom plate ribs, the left and right adjacent side-by-side concrete bottom plate ribs are connected through transverse prestress or wet joints, and are sequentially connected along a transverse bridge direction, and the corrugated steel webs are pre-buried at the outer sides of the side-by-side concrete bottom plate ribs on both sides.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202220243196.7U CN216891925U (en) | 2022-01-29 | 2022-01-29 | Wave form steel web combination case girder construction based on arch structure atress |
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| CN202220243196.7U CN216891925U (en) | 2022-01-29 | 2022-01-29 | Wave form steel web combination case girder construction based on arch structure atress |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114411523A (en) * | 2022-01-29 | 2022-04-29 | 福州大学 | Corrugated steel web plate combined box girder structure based on arch structure stress and construction method thereof |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114411523A (en) * | 2022-01-29 | 2022-04-29 | 福州大学 | Corrugated steel web plate combined box girder structure based on arch structure stress and construction method thereof |
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