CN209891055U - Hidden anchor cantilever beam type comb-tooth bridge expansion device - Google Patents
Hidden anchor cantilever beam type comb-tooth bridge expansion device Download PDFInfo
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- CN209891055U CN209891055U CN201920539026.1U CN201920539026U CN209891055U CN 209891055 U CN209891055 U CN 209891055U CN 201920539026 U CN201920539026 U CN 201920539026U CN 209891055 U CN209891055 U CN 209891055U
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Abstract
The utility model relates to a hidden anchor cantilever beam formula broach type bridge telescoping device, including locating two fishback on the expansion joint both sides bridge member respectively, two the broach of fishback is crisscross to be inlayed and is inserted, and every broach bottom is connected with vertical stiffening rib and constitutes for cantilever beam type structure, cantilever beam type structure passes through the hidden anchor of anchor arm-tie plate and fixes on the bridge member that corresponds the side, the anchor arm-tie plate links firmly and welds with the bridge member inside reinforcing bar that corresponds the side with corresponding side fishback stiff end and the vertical stiffening rib that corresponds respectively and even. The utility model discloses a set up vertical stiffening rib and the combination is cantilever beam type structure bottom the fishback to make the broach type telescoping device convert "beam type" structure system into by conventional "board-like" structure system, can increase telescoping device's cross-section inertia moment and cross-sectional rigidity effectively, improve telescoping device's life.
Description
Technical Field
The utility model belongs to the technical field of the bridge, concretely relates to hidden anchor cantilever beam formula broach type bridge telescoping device.
Background
The expansion device is a key part in a bridge member and plays an important role in realizing the function of the bridge. The common bridge expansion device has two types, namely a modulus bridge expansion device and a comb-tooth type bridge expansion device.
The comb plate type telescopic device is provided with a steel comb plate type and a steel flat plate superposition type, and the appearance damage form mainly comprises:
anchoring part damage;
secondly, the comb plate is damaged;
thirdly, rotating the control seat and the rotating shaft;
fourthly, the waterproof rubber strip is full of dust, garbage and water leakage.
From the condition of the damaged part of the steel telescopic device at present, the damage causes include design causes, processing technology problems, construction quality problems, management and maintenance problems and the like. The telescopic device is easy to deform in the processing and using processes, the tooth plate and the base plate are difficult to be attached, once a gap is generated, the stress on a connecting system and a connecting part is not favorable, and noise and vehicle jumping are caused; in addition, the problems of large traffic volume, frequent load impact, easy premature fatigue, loosening of fastening bolts, exposure of rotating and tilting comb tooth plates, easy clamping of gaps of the comb tooth plates by sundries and the like are caused, and the expansion function and the drainage function are influenced.
From the analysis of comb plate formula telescoping device atress characteristics, cause the reason of comb plate formula telescoping device disease mainly to have following several:
(1) the telescopic device cannot meet the requirement of transverse displacement; simultaneously, when the roof beam body takes place horizontal rotation, the interact atress between the fishback forms great shearing force to fixing bolt, and the bolt is easy to be split.
(2) The device can not meet the requirement of vertical deflection
The vertical rotation mainly refers to the deflection performance of the bridge expansion device under the action of load, the expansion device has no vertical rotation function, the device is fixed on a bridge deck at the beam end only by rivets, and when the device bears load and generates vertical deflection, the device forms larger drawing force on the beam body through the rivets, so that nuts are loosened or fall off frequently; when frequent impact loads act on the device, the device can be bent and deformed and comb teeth can be broken when the device is heavy.
(3) The adaptability of the traditional seam crossing type comb tooth type expansion device to longitudinal slopes is relatively poor
From the deformation analysis of roof beam, when the bridge longitudinal gradient is the flat slope, the adaptability of broach board formula telescoping device is can, but when indulging disconnected slope, the change adaptability of pinion board formula telescoping device to the slope is relatively poor.
Referring to fig. 1, the following can be seen: when the longitudinal section has a slope and the beam stretches, the steel plate of the toothed plate type telescopic device cannot automatically adapt to the change of the slope and becomes a broken line. If the schematic diagram is assumed that the gap at the beam end is 100cm, the longitudinal slope is 3% and the height difference between the two points AB is 3cm before the main beams on the two sides of the telescopic device are displaced, when the gap at the beam end is shortened to 50cm due to temperature change, the height difference between the two points AB is still 3cm, and the slope is increased from 3% to 6%; but the slope of steel fishback on the girder still is 3%, and the beam-ends after warping like this will give steel fishback a very big top force, and under this effect of force, the fishback just will warp, and the steel sheet just will warp, and the bolt is not hard up easily under the impact load effect.
SUMMERY OF THE UTILITY MODEL
The embodiment of the utility model provides a hidden anchor cantilever beam formula broach type bridge telescoping device can solve prior art's partial defect at least.
The embodiment of the utility model relates to a hidden anchor cantilever beam formula broach type bridge telescoping device, including locating two fishback on expansion joint both sides bridge member respectively, two the broach of fishback is crisscross to be inlayed and is inserted, and every broach bottom is connected with vertical stiffening rib and constitutes for cantilever beam type structure, cantilever beam type structure passes through the hidden anchor of anchor plate and fixes on the bridge member that corresponds the side, the anchor plate links firmly and welds with the bridge member inside reinforcement that corresponds the side with corresponding side fishback stiff end and the vertical stiffening rib that corresponds respectively.
As an embodiment, a horizontal stress dispersion steel plate is arranged on the bridge member on each side, the horizontal stress dispersion steel plate comprises an inclined section having an included angle with the horizontal plane, and each vertical stiffening rib is fixed on the inclined section on the corresponding side.
As one embodiment, the horizontal stress dispersion steel plate further comprises a horizontal section connected to the top end of the inclined section, and the horizontal section is welded with the corresponding comb plate.
As one example, each of the vertical stiffeners is in the form of an I-shape or T-shape.
In one embodiment, the internal reinforcing bars of the bridge member comprise portal reinforcing bars embedded in the bridge member.
As one embodiment, the hidden anchor cantilever type comb-tooth bridge expansion device further comprises a water stop structure connected to the two bridge members, wherein the water stop structure is located below the cantilever type structure.
The embodiment of the utility model provides a following beneficial effect has at least:
the utility model provides a hidden anchor cantilever beam formula broach type bridge telescoping device through set up vertical stiffening rib and the combination is cantilever beam type structure in the fishback bottom, makes the broach type telescoping device convert "beam type" structure system into by conventional "board-like" structure system, can increase the cross-section inertia moment and the cross-sectional rigidity of telescoping device effectively, improves the life of telescoping device. Adopt cantilever beam formula structure anchor to draw to fix on the bridge member to cantilever beam formula structure is whole as structure atress system, and it has not only increased the anchoring performance of fishback, no longer adopts traditional bolted connection form simultaneously, has avoided the drawback that traditional crab-bolt structural style easily breaks away from.
The embodiment of the utility model provides a further following beneficial effect has:
the utility model provides a hidden anchor cantilever beam formula broach type bridge telescoping device, the bridge construction seam both sides are laid to the fishback symmetry. Because the telescoping device pinion rack all with the displacement of structural joint central line or rotate, consequently the bridge longitudinal slope or the vertical difference in height that the roof beam body is flexible and is leaded to do not have the influence to the structure, the last top force of counter plate that the pinion rack structure can not receive to lead to by vertical difference in height.
The embodiment of the utility model provides a further following beneficial effect has:
by adopting the horizontal stress dispersion steel plate, when the cantilever beam type structure is integrally stressed in a synergistic manner, the impact load of the wheels can be transmitted to the bridge member through the horizontal stress dispersion steel plate, so that the contact area between the cantilever beam type structure and the concrete structure of the bridge member is increased, the load is dispersed to the concrete structure of the bridge, the local stress of the concrete of the bridge is avoided, and the concrete in the expansion joint installation area can be better protected; particularly, the structure that the inclined section is arranged on the basis of the horizontal stress dispersion steel plate decomposes the borne wheel impact load into horizontal stress and vertical stress, so that the whole bridge member bears the wheel impact.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a high differential longitudinal view of a beam end provided in the background art;
fig. 2 is a schematic cross-sectional structure view of a hidden anchor cantilever beam type comb-tooth bridge expansion device provided by an embodiment of the present invention;
fig. 3 and 4 are schematic elevation structural diagrams of two forms of cantilever beam structures provided by the embodiment of the present invention;
fig. 5 is a plan view of the hidden anchor cantilever beam type comb-tooth bridge expansion device provided by the embodiment of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.
Example one
As shown in fig. 2-5, the embodiment of the utility model provides a hidden anchor cantilever beam formula broach type bridge telescoping device, including locating two fishback 1 on expansion joint both sides bridge member 8 respectively, two the broach of fishback 1 is crisscross to be inserted, and every broach bottom is connected with vertical stiffening rib 2 and constitutes for cantilever beam type structure, cantilever beam type structure passes through the hidden anchor of anchor plate 4 and fixes on the bridge member 8 that corresponds the side, anchor plate 4 links firmly and welds with the bridge member inside reinforcement that corresponds the side with the vertical stiffening rib 2 that corresponds side fishback stiff end and correspondence respectively.
As will be easily understood, the bridge member 8 may be a bridge body or a bridge abutment, i.e. two bridge bodies located at two sides of the expansion joint, or a bridge body and a bridge abutment located at two sides of the expansion joint respectively.
The comb plate 1 is generally a steel plate, and generally includes a ridge plate and a plurality of comb teeth provided on the ridge plate, wherein the ridge plate is connected to the bridge member 8 on the corresponding side, and each comb tooth constitutes a free end of the comb plate 1. The structure of the two comb plates 1 with the interleaved inserted comb teeth is a conventional structure of a comb-tooth type bridge expansion device in the field, and details are not described here. Obviously, the vertical stiffeners 2 on both sides of the expansion joint are also in a staggered structure.
As shown in fig. 3 and 4, the vertical stiffener 2, which may be in the form of an "I-shaped" or "T-shaped" stiffener, forms a cantilever beam structure with the comb plate 1, and simultaneously ensures that the corresponding comb plate 1 can be supported well. In this embodiment, the vertical stiffening rib 2 is preferably the vertical stiffening rib 2 welded to the bottom of the corresponding comb plate 1, and the connection structure with the comb plate 1 is reliable and stable, and has good cooperative stress performance and convenient construction.
The anchor plate 4 is generally a steel plate, and is welded and fixed with the comb plate 1, and for the steel vertical stiffening ribs 2 such as the vertical stiffening rib 2, the anchor plate 4 and the vertical stiffening rib 2 are also preferably welded and fixed; the welding fixing mode can enhance the overall cooperative stress performance of the cantilever beam type structure.
For the fixing mode of the anchor plate 4 and the bridge member 8 on the corresponding side, as shown in fig. 2, a portal type steel bar 6 can be embedded in the bridge member 8 and welded with the anchor plate 4 on the corresponding side through the portal type steel bar 6; specifically, the portal type reinforcing steel bars 6 are of a square frame structure, the structure below the portal type reinforcing steel bars is broken, when the portal type reinforcing steel bars 6 are installed, the portal type reinforcing steel bars 6 are partially embedded when a bridge body or a bridge abutment is prepared, double-sided welding is performed between the anchor pulling plate 4 and the portal type reinforcing steel bars 6, and the stability of the cantilever beam type structure can be further improved.
Further, as shown in fig. 2, the anchor plate 4 is further connected to the corresponding bridge member 8 through the anchor steel bar 5, preferably, the door frame type steel bar 6 is used for realizing the fixed connection between the anchor plate 4 and the first cast structure of the bridge member 8, and the anchor steel bar 5 is used for realizing the fixed connection between the anchor plate 4 and the second cast structure of the bridge member 8, so as to ensure the stability and reliability of the connection structure between the anchor plate 4 and the bridge member 8 and the overall stress performance of the cantilever beam type structure.
The hidden anchor cantilever beam type comb-tooth bridge expansion device provided by the embodiment has the advantages that the vertical stiffening ribs are arranged at the bottom of the comb-tooth plate 1 and combined into a cantilever beam type structure, so that the comb-tooth type expansion device is converted from a conventional plate type structure system into a beam type structure system, the section inertia moment and section rigidity of the expansion device can be effectively increased, and the service life of the expansion device is prolonged.
Adopt cantilever beam formula structure anchor to draw to fix on bridge member 8 to cantilever beam formula structure is whole as structure atress system, through hidden anchor structural style, and it has not only increased fishback 1's anchoring performance, no longer adopts traditional bolted connection form simultaneously, has avoided the drawback that traditional crab-bolt structural style easily breaks away from.
The comb plate 1 is symmetrically arranged on two sides of a bridge structure seam, and because the telescopic device toothed plate 1 is displaced or rotated along the center line of the structure seam, the vertical height difference caused by the longitudinal slope of the bridge or the extension and contraction of the beam body has no influence on the structure, and the comb plate structure cannot receive the upward jacking force of the counter plate caused by the longitudinal height difference.
In addition, along with the increase of the length of the bridge beam and the improvement of the type of the telescopic device, the traditional comb plate 1 technology increases the thickness of a steel plate to improve the structural rigidity, so that the larger the structural type is, the deeper the groove depth between tooth gaps is; in the embodiment, due to the adoption of the unique design of the beam type system, along with the increase of the type of the expansion device, the required structural rigidity can be calculated by only partially increasing the thickness of the two comb plates 1 and partially increasing the height (or the thickness of the steel plate of the stiffening rib) of the vertical stiffening rib 2, so that the depth of the tooth gaps can be reduced, for example, the 400mm type expansion device is adopted, the depth of the tooth plate groove of the traditional expansion device generally reaches 45mm, and the depth of the tooth gap groove is only 20mm by adopting the scheme.
Further preferably, as shown in fig. 5, the vertical stiffening ribs 2 are the same in number as the comb teeth and are arranged in a one-to-one correspondence manner, that is, the bottom of each comb tooth is connected with one vertical stiffening rib 2, so that a supporting effect on the comb plate 1 is ensured, and the impact resistance of the telescopic device is enhanced.
Further optimizing the structure of the hidden anchor cantilever beam type comb-tooth bridge expansion device, as shown in fig. 2, a horizontal stress dispersion steel plate 3 is arranged on the bridge member 8 on each side, the horizontal stress dispersion steel plate 3 comprises an inclined section having an included angle with the horizontal plane, and each vertical stiffening rib 2 is respectively fixed on the inclined section on the corresponding side. Based on the horizontal stress dispersion steel plate 3, when the cantilever beam type structure is integrally stressed in a coordinated manner, the wheel impact load can be transmitted to the bridge member 8 through the horizontal stress dispersion steel plate 3, the contact area between the cantilever beam type structure and the concrete structure of the bridge member 8 is increased, the load is uniformly dispersed to the bridge concrete structure, the local stress of the bridge concrete is avoided, and the bridge concrete in the installation area of the telescopic device can be better protected; particularly, because of the structure that the horizontal stress dispersion steel plate 3 is provided with the inclined section, the borne wheel impact load is decomposed into horizontal stress and vertical stress, so that the whole bridge member 8 bears the wheel impact, and the protection effect on bridge concrete is better.
Further preferably, as shown in fig. 2, the horizontal stress dispersion steel plate 3 further includes a horizontal section connected to the top end of the inclined section, and the horizontal section is welded to the corresponding comb plate 1. Based on this structure, make horizontal stress dispersion steel sheet 3 more reliable and more stable with the assembly structure of fishback 1, vertical stiffening rib 2 etc. especially still connect anchor plate 4 as an organic wholely, make anchor plate 4, horizontal stress dispersion steel sheet 3, fishback 1 and vertical stiffening rib 2 connect to be a whole steel construction system, the atress effect is better in coordination.
As shown in fig. 2, the horizontal stress dispersion steel plate 3 further comprises a vertical section, the vertical section is connected to the bottom end of the inclined section, and the vertical section is welded and fixed with the corresponding anchor plate 4, so that the structural stability of the integral steel structure system formed by connecting the anchor plate 4, the horizontal stress dispersion steel plate 3, the comb plate 1 and the vertical stiffening ribs 2 is further improved, and the vertical impact load can be better transmitted.
The inclined section is preferably inclined downwards from one end far away from the expansion joint to one end close to the expansion joint, and the inclined sections on two sides are in a bell mouth structure with a wide upper part and a narrow lower part, so that the wheel load can be transmitted more reliably.
Further optimizing the structure of the hidden-anchor cantilever beam type comb-tooth type bridge expansion device, as shown in fig. 2, the hidden-anchor cantilever beam type comb-tooth type bridge expansion device further comprises a water stop structure 7 connected to the two bridge members 8, and the water stop structure 7 is located below the cantilever beam type structure. The water stopping structure 7 can adopt a water stopping member which is conventional in the field, for example, a water stopping rubber strip is adopted, and two ends of the water stopping rubber strip are respectively fixed on the bridge members 8 at two sides of the expansion joint.
In other embodiments, still be provided with in fishback 1 below and prevent sediment dustproof construction, should prevent sediment dustproof construction and can adopt coincide steel sheet structure etc. specifically, including fixing two dustproof steel sheets on expansion joint both sides bridge component 8 respectively, wherein the free end of a dustproof steel sheet is overlapped and is laminated in another dustproof steel sheet upper surface, when satisfying along with 8 relative motion requirements of both sides bridge component, guarantees dustproof effect of preventing the sediment. The structure of the laminated steel plate is preferably positioned below each vertical stiffening rib 2, and more preferably below the inclined section of the horizontal stress dispersion steel plate 3; more preferably, the water stop structure 7 is located above the water stop structure.
The above description is only a preferred embodiment of the present invention, and should not be taken as limiting the invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (6)
1. The utility model provides a hidden anchor cantilever beam formula broach type bridge telescoping device, is including locating two fishback on the expansion joint both sides bridge member respectively, two fishback's broach is crisscross inlays and inserts its characterized in that: every broach bottom is connected with vertical stiffening rib and constitutes for cantilever beam type structure, cantilever beam type structure passes through the dark anchor of anchor plate and fixes on the bridge member that corresponds the side, the anchor plate links firmly and welds with the inside reinforcing bar of bridge member that corresponds the side with the vertical stiffening rib that corresponds side fishback stiff end and corresponds respectively.
2. The hidden-anchor cantilever beam comb-tooth bridge expansion device according to claim 1, wherein: the bridge member of each side is provided with a horizontal stress dispersion steel plate, the horizontal stress dispersion steel plate comprises an inclined section with an included angle with the horizontal plane, and each vertical stiffening rib is fixed on the inclined section of the corresponding side respectively.
3. The hidden-anchor cantilever beam comb-tooth bridge expansion device according to claim 2, wherein: the horizontal stress dispersion steel plate further comprises a horizontal section connected to the top end of the inclined section, and the horizontal section is welded with the corresponding comb plate.
4. The hidden-anchor cantilever beam comb-tooth bridge expansion device according to claim 2, wherein: each of the vertical stiffeners is in the form of an I-shape or a T-shape.
5. The hidden-anchor cantilever beam comb-tooth bridge expansion device according to claim 1, wherein: the internal reinforcing steel bars of the bridge member comprise portal type reinforcing steel bars which are embedded in the bridge member.
6. The hidden-anchor cantilever beam comb-tooth bridge expansion device according to claim 1, wherein: the water stopping structure is connected to the two bridge members and is positioned below the cantilever beam type structure.
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| CN201920539026.1U CN209891055U (en) | 2019-04-19 | 2019-04-19 | Hidden anchor cantilever beam type comb-tooth bridge expansion device |
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| CN201920539026.1U CN209891055U (en) | 2019-04-19 | 2019-04-19 | Hidden anchor cantilever beam type comb-tooth bridge expansion device |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109930480A (en) * | 2019-04-19 | 2019-06-25 | 中铁第四勘察设计院集团有限公司 | Dark anchor beam type comb-tooth bridge expansion device |
| CN113026549A (en) * | 2021-04-09 | 2021-06-25 | 天津桥通科技发展有限公司 | Novel embedded unit type multidirectional displacement bridge expansion device with ultra-long service life |
-
2019
- 2019-04-19 CN CN201920539026.1U patent/CN209891055U/en active Active
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109930480A (en) * | 2019-04-19 | 2019-06-25 | 中铁第四勘察设计院集团有限公司 | Dark anchor beam type comb-tooth bridge expansion device |
| CN109930480B (en) * | 2019-04-19 | 2024-03-26 | 中铁第四勘察设计院集团有限公司 | Hidden anchor cantilever beam type comb-tooth bridge expansion device |
| CN113026549A (en) * | 2021-04-09 | 2021-06-25 | 天津桥通科技发展有限公司 | Novel embedded unit type multidirectional displacement bridge expansion device with ultra-long service life |
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