阅读说明：本技术 一种模组式钢伸缩缝及其工作过程 (Module type steel expansion joint and working process thereof ) 是由 周勇军 王业路 宋一凡 赵煜 周先功 沈传东 孙楠楠 于 2019-09-27 设计创作，主要内容包括：本发明公开一种模组式钢伸缩缝及其工作过程,若干个中梳齿板并排设置并设置于底垫板的上方,每个中梳齿板的下端螺纹连接有中螺旋轴,中螺旋轴的下端与底垫板之间可旋转连接,中螺旋轴的下端同轴设有齿轮；滑条的一端与底垫板滑动连接,滑条的该端设有齿锤,当滑条滑动时,齿锤能够驱动中螺旋轴下端的齿轮转动；滑条的另一端与主梁二铰接；边梳齿板设置于中梳齿板的一侧,尾梳齿板和钢搭板位于中梳齿板的另一侧,边梳齿板与主梁一固定连接,转轴板固定安装于主梁二并与钢搭板轴连接；尾梳齿板安装于底垫板上,钢搭板的一端搭在尾梳齿板上。本发明解决了桥梁结构受温度、收缩和徐变作用变形后,两联之间无法平缓过度,行车不舒适的问题。(The invention discloses a modular steel expansion joint and a working process thereof.A plurality of middle comb plates are arranged side by side and are arranged above a bottom backing plate, the lower end of each middle comb plate is in threaded connection with a middle screw shaft, the lower end of the middle screw shaft is rotatably connected with the bottom backing plate, and the lower end of the middle screw shaft is coaxially provided with a gear; one end of the sliding strip is connected with the bottom cushion plate in a sliding mode, a tooth hammer is arranged at the end of the sliding strip, and when the sliding strip slides, the tooth hammer can drive a gear at the lower end of the middle spiral shaft to rotate; the other end of the sliding strip is hinged with the second main beam; the side comb plate is arranged on one side of the middle comb plate, the tail comb plate and the steel strap plate are positioned on the other side of the middle comb plate, the side comb plate is fixedly connected with the first main beam, and the rotating shaft plate is fixedly arranged on the second main beam and is connected with the steel strap plate shaft; the tail comb plate is arranged on the bottom base plate, and one end of the steel lapping plate is lapped on the tail comb plate. The invention solves the problems that the bridge structure cannot be smoothly and excessively deformed under the action of temperature, shrinkage and creep, and the driving is uncomfortable.)

1. A modular steel expansion joint is used for adjusting displacement and connection between a first main beam (1) and a second main beam (2), and is characterized by comprising a side comb plate (4), a middle comb plate (5), a tail comb plate (30), a steel butt strap (3), a bottom cushion plate (6), a rotating shaft plate (7) and a sliding strip (8), wherein the bottom cushion plate (6) is fixedly arranged on the first main beam (1); a plurality of middle comb plates (5) are arranged along the seam width direction, and a plurality of middle comb plates (5) are arranged side by side; the middle comb plate (5) is arranged above the bottom cushion plate (6), the lower end of each middle comb plate (5) is in threaded connection with a middle screw shaft (13), the lower end of each middle screw shaft (13) is rotatably connected with the bottom cushion plate (6), and the lower end of each middle screw shaft (13) is coaxially provided with a gear (33);

one end of the sliding strip (8) is connected with the bottom cushion plate (6) in a sliding mode, a tooth hammer (24) capable of being meshed with the gear (33) is arranged at the end of the sliding strip (8), the tooth hammer (24) adopts a section of rack, and when the sliding strip (8) slides, the tooth hammer (24) can drive the gear (33) at the lower end of the middle screw shaft (13) to rotate; when the slide bar (8) slides towards the bottom backing plate (6), the middle screw shaft (13) rotates and enables the middle comb plate (5) to move downwards; when the slide bar (8) slides towards the direction far away from the bottom backing plate (6), the middle screw shaft (13) rotates and enables the middle comb plate (5) to move upwards; the other end of the sliding strip (8) is hinged with the second main beam (2);

the side comb plate (4) is arranged on one side of the middle comb plate (5), the tail comb plate (30) and the steel strap plate (3) are located on the other side of the middle comb plate (5), the side comb plate (4) is fixedly connected with the main beam I (1), and the rotating shaft plate (7) is fixedly installed on the main beam II (2) and is connected with the steel strap plate (3) through a shaft; the tail comb plate (30) is arranged on the bottom base plate (6), and one end of the steel lapping plate (3) is lapped on the tail comb plate (30).

2. The modular steel expansion joint according to claim 1, wherein the structure of the middle comb plate (5) is divided into an upper layer and a lower layer, the upper layer is a W-shaped steel bar (21), the lower layer is a rectangular long steel bar (19), the rectangular long steel bar (19) is provided with a threaded spiral through hole (20) at intervals of a preset distance, and the upper end of the middle spiral shaft (13) is in fit connection with the spiral through hole (20); the upper layer and the lower layer are of an integral structure; between two adjacent middle comb plates (5), the W-shaped steel bars (21) on the upper layer are embedded mutually.

3. A modular steel expansion joint according to claim 2, characterized in that rubber strips (15) are arranged on both sides of the W-shaped steel strip on the upper layer of the middle comb plate (5).

4. The modular steel expansion joint as claimed in claim 2, wherein the side comb plate (4) comprises a rectangular steel plate, a comb-shaped structure (4-2) is arranged on one side of the upper part of the rectangular steel plate (4-1) close to the middle comb plate (5), and the comb-shaped structure (4-2) is W-shaped and is matched with the W-shaped steel bar (21); the rectangular steel plate (4-1) is fixedly connected with the bottom base plate (6) and the first main beam (1).

5. A modular steel expansion joint according to claim 4, characterized in that the comb-like structure (4-2) is provided with a rubber strip in front of the side close to the middle comb plate (5).

6. A modular steel expansion joint according to claim 2, characterized in that the steel attachment plate (3) is a steel plate with a comb-shaped edge structure; the comb tooth structure faces one side of the middle comb plate (5), and the thickness of the comb tooth structure is gradually reduced towards the direction of the middle comb plate (5); the end part of the comb tooth structure is provided with a second rubber strip (18).

7. A modular steel expansion joint according to claim 6, characterized in that the thickness of the comb structure towards one side edge of the middle comb plate (5) is half of the normal section of the steel attachment plate (3).

8. The modular steel expansion joint of claim 1, wherein the bottom plate (6) is a U-shaped steel plate (27), and the bottom edge of the bottom plate (6) is fixed to the first main beam (1); the plurality of middle comb plates (5) are arranged on the bottom edge of the bottom base plate (6) and are positioned between the two wing edges of the bottom base plate (6); the lower end of the middle screw shaft (13) is rotatably connected with the bottom edge of the bottom cushion plate (6); the bottom edge of the bottom cushion plate (6) is provided with a slideway (14) for the slide strip (8) to slide.

9. The modular steel expansion joint of claim 8, wherein the slideway (14) comprises a sliding groove (22) and a stop block (23) for limiting the sliding strip (8), the sliding groove (22) is in adaptive connection with the sliding strip (8), and the sliding groove (22) and the stop block (23) are welded with the bottom edge of the bottom cushion plate (6); the slide bar (8) is connected with the second main beam (2) through a semi-hoop (17).

10. The process of operating a modular steel expansion joint of any of claims 1 to 9, comprising the steps of: the first main beam (1) and the second main beam (2) move relatively, so that the distance between the first main beam (1) and the second main beam (2) becomes smaller or larger;

when the distance between the first main beam (1) and the second main beam (2) is reduced, the second main beam (2) drives the sliding strip (8) and the steel access plate (3) to move towards the first main beam (1), the tooth hammer (24) drives the middle screw shaft (13) to rotate, the middle screw shaft (13) rotates to enable the middle comb plate (5) to move downwards, space is reserved for the steel access plate (3) after the middle comb plate (5) moves downwards, and the steel access plate (3) is just lapped on the corresponding descending middle comb plate (5);

when the distance between the first main beam (1) and the second main beam (2) is increased, the second main beam (2) drives the sliding strip (8) and the steel access plate (3) to move towards the direction far away from the first main beam (1), the tooth hammer (24) drives the middle screw shaft (13) to rotate, the middle screw shaft (13) rotates to enable the middle comb plate (5) to move upwards, the space reserved after the steel access plate (3) moves is filled after the middle comb plate (5) moves upwards, and the steel access plate (3) is just lapped on the corresponding descending middle comb plate (5).

Technical Field

The invention relates to the field of bridge engineering, in particular to a modular steel expansion joint and a working process thereof.

Background

In order to meet the requirement of bridge deck deformation, expansion joints are usually provided between two beam ends, between a beam end and an abutment, or at the hinge joint of a bridge. The expansion joint is required to freely expand and contract in two directions parallel to and perpendicular to the axis of the bridge, and the expansion joint is firm and reliable, and when a vehicle runs, the vehicle is smooth and free of sudden jump and noise. The bridge expansion joints function to accommodate displacements and couplings between the superstructure caused by vehicle loads and the bridge. Once the telescopic device is damaged, the speed, comfort and safety of the vehicle are seriously influenced, and even a vehicle safety accident is caused. The existing expansion joints mostly adopt a general butt joint type or modulus type expansion device, a rubber combined shear type bridge expansion joint, a seamless bridge expansion joint and the like; the butt joint type expansion joint is used for a conventional bridge with the expansion amount of below 80mm, the bridge is not seamless, and criss-cross grooves exist, so that the driving comfort is influenced to a certain extent; the rubber strip is generally left in the middle of the modulus type telescopic device, so that the modulus type telescopic device is easy to age and damage, and the V-shaped groove influences the driving comfort; the seamless bridge expansion joint is a structure that when the joint structure does not extend out of the bridge surface, elastic materials are filled in the expansion gaps at the ends of the bridge and waterproof materials are paved, then viscoelastic composite materials are paved on the bridge deck pavement layer, so that the bridge deck pavement and other pavement parts at the expansion joint position form a continuous body, and the expansion is borne by the deformation of materials such as asphalt concrete and the like of the joint; the composite material has high relative cost, is not popularized and used in a large range, and has questionable economy.

Disclosure of Invention

The invention aims to provide a modular steel expansion joint and a working process thereof, which aim to solve the problem that a bridge structure is easy to deform under the action of temperature, contraction and creep.

The technical scheme adopted by the invention is as follows:

a modular steel expansion joint is used for adjusting displacement and connection between a first main beam and a second main beam and comprises the first main beam, the second main beam, a side comb plate, a middle comb plate, a tail comb plate, a steel butt strap, a bottom cushion plate, a rotating shaft plate and a sliding strip, wherein the bottom cushion plate is fixedly arranged on the first main beam; the plurality of middle comb plates are arranged along the seam width direction and arranged side by side; the middle comb plate is arranged above the bottom base plate, the lower end of each middle comb plate is in threaded connection with a middle screw shaft, the lower end of each middle screw shaft is rotatably connected with the bottom base plate, and the lower end of each middle screw shaft is coaxially provided with a gear;

one end of the sliding strip is connected with the bottom cushion plate in a sliding mode, a tooth hammer capable of being meshed with the gear is arranged at the end of the sliding strip, the tooth hammer adopts a section of rack, and when the sliding strip slides, the tooth hammer can drive the gear at the lower end of the middle spiral shaft to rotate; when the slide bar slides to the bottom backing plate, the middle screw shaft rotates and enables the middle comb plate to move downwards; when the slide bar slides towards the direction far away from the bottom cushion plate, the middle screw shaft rotates and enables the middle comb plate to move upwards; the other end of the sliding strip is hinged with the second main beam;

the side comb plate is arranged on one side of the middle comb plate, the tail comb plate and the steel strap plate are positioned on the other side of the middle comb plate, the side comb plate is fixedly connected with the first main beam, and the rotating shaft plate is fixedly arranged on the second main beam and is connected with the steel strap plate shaft; the tail comb plate is arranged on the bottom base plate, and one end of the steel lapping plate is lapped on the tail comb plate.

The structure of the middle comb plate is divided into an upper layer and a lower layer, the upper layer is a W-shaped steel bar, the lower layer is rectangular long steel bar, the rectangular long steel bar is provided with a threaded spiral through hole every preset distance, and the upper end of the middle spiral shaft is connected with the spiral through hole in a matched mode; the upper layer and the lower layer are of an integral structure; between two adjacent comb plates, the W-shaped steel bars on the upper layer are embedded into each other.

Well fishback upper W shape steel bar both sides set up rubber strip one, and rubber strip one is arranged in sealed waterproof and prevent that the gap is too big to cause silt to block up between adjacent well fishback (5) between the fishback.

The side comb plate comprises a rectangular steel plate, one side of the upper part of the rectangular steel plate, which is close to the middle comb plate, is provided with a comb-shaped structure, and the comb-shaped structure is W-shaped and is matched with the W-shaped steel bar in shape; the rectangular steel plate is fixedly connected with the bottom base plate and the first main beam.

A rubber strip is arranged in front of one side of the tooth-shaped structure close to the middle comb plate.

The steel lapping plate is a steel plate with a comb tooth structure at the edge; the comb tooth structure faces one side of the middle comb plate, the comb tooth structure faces the direction of the middle comb plate, and the thickness of the comb tooth structure is gradually reduced; the end part of the comb tooth structure is provided with a second rubber strip.

The thickness of the comb tooth structure towards one side edge of the middle comb tooth plate is half of the normal section of the steel lapping plate.

The bottom plate is a U-shaped steel plate, and the bottom edge of the bottom plate is fixed to the first main beam; the plurality of middle comb plates are arranged on the bottom edge of the bottom cushion plate and positioned between the two wing edges of the bottom cushion plate; the lower end of the middle spiral shaft is rotatably connected with the bottom edge of the bottom cushion plate; the bottom edge of the bottom base plate is provided with a slideway for the slide strip to slide.

The slideway comprises a sliding groove and a stop block for limiting the sliding strip, the sliding groove is connected with the sliding strip in a matching way, and the sliding groove and the stop block are welded with the bottom edge of the bottom base plate; the slide bar is connected with the second main beam through a half hoop.

The working process of the modular steel expansion joint comprises the following steps: the first main beam and the second main beam move relatively, so that the distance between the first main beam and the second main beam becomes smaller or larger;

when the distance between the first main beam and the second main beam is reduced, the second main beam drives the sliding strip and the steel butt strap to move towards the first main beam, the tooth hammer drives the middle screw shaft to rotate, the middle screw shaft rotates to enable the middle comb plate to move downwards, a space is reserved for the steel butt strap after the middle comb plate moves downwards, and the steel butt strap is just lapped on the correspondingly lowered middle comb plate;

when the distance between the first main beam and the second main beam is increased, the second main beam drives the sliding strip and the steel access plate to move in the direction far away from the first main beam, the tooth hammer drives the middle screw shaft to rotate, the middle screw shaft rotates to enable the middle comb plate to move upwards, the space reserved after the steel access plate moves is filled after the middle comb plate moves upwards, and the steel access plate is just lapped on the corresponding descending middle comb plate.

The invention has the following beneficial effects:

in the modular steel expansion joint, the lower end of each middle comb plate is in threaded connection with a middle screw shaft, the lower end of the middle screw shaft is rotatably connected with a bottom cushion plate, and the lower end of the middle screw shaft is coaxially provided with a gear; one end of the sliding strip is connected with the bottom cushion plate in a sliding mode, a tooth hammer capable of being meshed with the gear is arranged at the end of the sliding strip, and when the sliding strip slides, the tooth hammer can drive the gear at the lower end of the middle spiral shaft to rotate; when the slide bar slides towards the bottom base plate (namely, when the gap between the first main beam and the second main beam is reduced), the middle screw shaft rotates and enables the middle comb plate to move downwards, at the moment, a space is reserved for the steel butt strap after the middle comb plate moves downwards, and the steel butt strap is just lapped on the correspondingly lowered middle comb plate; when the slide bar slides in the direction far away from the bottom base plate, the middle screw shaft rotates and enables the middle comb plate to move upwards, at the moment, the middle comb plate moves upwards to fill the space reserved after the steel butt plate moves, and the steel butt plate is just lapped on the correspondingly descending middle comb plate; the working principle ensures that the joint between the first main beam and the second main beam can be gentle and excessive, the joint is smooth, and the requirement on driving comfort is met.

The working process of the modular steel expansion joint ensures that the joint between the first main beam and the second main beam can be in gradual transition, so that a travelling crane can stably pass through the joint between the first main beam and the second main beam, and the travelling comfort is ensured.

Drawings

FIG. 1 is a connection diagram of a modular steel expansion joint device according to the present invention;

FIG. 2 is a first three-dimensional structural view of the modular steel expansion joint assembly of the present invention;

FIG. 3 is a second three-dimensional structural view of the modular steel expansion joint assembly of the present invention;

FIG. 4 is a side view of the modular steel expansion joint assembly of the present invention;

FIG. 5 is a first internal view of the modular steel expansion joint assembly of the present invention;

FIG. 6 is a second internal view of the modular steel expansion joint assembly of the present invention;

FIG. 7 is a third internal view of the modular steel expansion joint assembly of the present invention;

FIG. 8 is a view showing the installation position of the anchoring pad block in the modular steel expansion joint device of the present invention

Fig. 9 is a schematic view of the modular steel expansion joint device of the present invention after centering a plurality of middle comb plates;

FIG. 10 is a three-dimensional structure of the insole board in the modular steel expansion joint device of the present invention;

FIG. 11 is a detailed view of the bottom plate of the modular steel expansion joint device of the present invention;

FIG. 12 is a schematic view showing the connection of screw shafts in the modular steel expansion joint device of the present invention;

FIG. 13 is a schematic view showing the connection of side screw shafts in the modular steel expansion joint device of the present invention;

FIG. 14 is a diagram showing the relative positions of the slide bar and the slide way in the modular steel expansion joint device of the present invention;

FIG. 15 is a three-dimensional structural view of a steel strap in the modular steel expansion joint assembly of the present invention;

FIG. 16 is a detail view of the steel strap of the modular steel expansion joint assembly of the present invention;

FIG. 17 is a three-dimensional structural view of a side comb plate in the modular steel expansion joint device of the present invention;

FIG. 18 is a detail view of the side comb plate of the modular steel expansion joint device of the present invention;

FIG. 19 is a three-dimensional configuration of a comb plate in the modular steel expansion joint device of the present invention;

FIG. 20 is a detailed structural view of a comb plate in the modular steel expansion joint device of the present invention;

FIG. 21 is a detailed view of the pivot plate of the modular steel expansion joint assembly of the present invention;

FIG. 22 is a schematic view of the connection of the pivot plate in the modular steel expansion joint apparatus of the present invention;

in the figure, 1-a first main beam, 2-a second main beam, 3-a steel butt strap, 4-a comb plate, 4-a rectangular steel plate, 4-a 2-a comb tooth structure, 5-a middle comb plate, 6-a base plate, 7-a rotating shaft plate, 8-a slide bar, 9-a threaded steel bar, 10-an anchoring cushion block, 11-a second threaded steel bar, 12-an edge screw shaft, 13-a middle screw shaft, 14-a slide rail, 15-a first rubber bar, 16-a pin shaft, 17-a half hoop, 18-a second rubber bar, 19-a rectangular long steel bar, 20-a spiral through hole, 21-a W-shaped steel bar, 22-a slide groove, 23-a stop block, 24-a hammer, 25-a guide rod, 26-a half hoop through hole, 27-a U-shaped steel plate, 28-a threaded steel bar through hole, 29-pin shaft groove, 30-tail comb plate, 31-nut, 32-twisted steel bar, three and 33-gear.

Detailed Description

The invention is further described below with reference to the figures and examples.

Referring to fig. 1 to 7, the modular steel expansion joint of the present invention is used for adjusting the displacement and connection between a primary beam 1 and a secondary beam 2, and includes a side comb plate 4, a middle comb plate 5, a tail comb plate 30, a steel strap 3, a bottom plate 6, a rotating shaft plate 7 and a slide bar 8, wherein the bottom plate 6 is fixedly installed on the primary beam 1; a plurality of middle comb plates 5 are arranged along the seam width direction, and a plurality of middle comb plates 5 are arranged side by side; the plurality of middle comb plates 5 are arranged above the bottom cushion plate 6, the lower end of each middle comb plate 5 is in threaded connection with a middle screw shaft 13, the lower end of each middle screw shaft 13 is rotatably connected with the bottom cushion plate 6, and the lower end of each middle screw shaft 13 is coaxially provided with a gear 33; one end of the slide bar 8 is connected with the bottom cushion plate 6 in a sliding manner, the end of the slide bar 8 is provided with a tooth hammer 24 which can be meshed with the gear 33, the tooth hammer 24 adopts a section of rack, and when the slide bar 8 slides, the tooth hammer 24 can drive the gear 33 at the lower end of the middle screw shaft 13 to rotate; when the slide bar 8 slides towards the bottom cushion plate 6, the middle screw shaft 13 rotates and enables the middle comb plate 5 to move downwards; when the slide bar 8 slides in the direction far away from the bottom cushion plate 6, the middle screw shaft 13 rotates and enables the middle comb plate 5 to move upwards; the other end of the sliding strip 8 is hinged with the second main beam 2; the side comb plate 4 is arranged on one side of the middle comb plate 5, the tail comb plate 30 and the steel strap 3 are positioned on the other side of the middle comb plate 5, the side comb plate 4 is fixedly connected with the main beam I1, and the rotating shaft plate 7 is fixedly arranged on the main beam II 2 and is connected with the steel strap 3 through a shaft; the tail comb plate 30 is arranged on the bottom base plate 6, and one end of the steel lapping plate 3 is lapped on the tail comb plate 30.

When the modular steel expansion joint works, the modular steel expansion joint comprises the following components: the first main beam 1 and the second main beam 2 move relatively, so that the distance between the first main beam 1 and the second main beam 2 becomes smaller or larger;

when the distance between the first main beam 1 and the second main beam 2 is smaller, the second main beam 2 drives the sliding strip 8 and the steel access plate 3 to move towards the first main beam 1, the tooth hammer 24 drives the middle screw shaft 13 to rotate, the middle screw shaft 13 rotates to enable the middle comb plate 5 to move downwards, a space is reserved for the steel access plate 3 after the middle comb plate 5 moves downwards, and the steel access plate 3 is just lapped on the corresponding descending middle comb plate 5;

when the distance between the first main beam 1 and the second main beam 2 is increased, the second main beam 2 drives the sliding strip 8 and the steel attachment strap 3 to move in the direction away from the first main beam 1, the tooth hammer 24 drives the middle screw shaft 13 to rotate, the middle screw shaft 13 rotates to enable the middle comb plate 5 to move upwards, the space reserved after the steel attachment strap 3 moves is filled after the middle comb plate 5 moves upwards, and the steel attachment strap 3 is just lapped on the corresponding descending middle comb plate 5.

As a preferred embodiment of the present invention, referring to fig. 1 to 4, 19 and 20, the structure of the middle comb plate 5 of the present invention is divided into an upper layer and a lower layer, wherein the upper layer is a W-shaped steel bar 21, the lower layer is a rectangular long steel bar 19, the rectangular long steel bar 19 is provided with a threaded spiral through hole 20 at intervals of a predetermined distance, and the upper end of the middle spiral shaft 13 is connected with the spiral through hole 20 in a matching manner; the upper layer and the lower layer are of an integral structure; between two adjacent middle comb plates 5, the upper W-shaped steel bars 21 are embedded into each other.

As a preferred embodiment of the present invention, as shown in fig. 20, rubber strips 15 are arranged on both sides of the W-shaped steel strip on the upper layer of the middle comb plate 5, and the rubber strips 15 are used for sealing and waterproofing between the adjacent middle comb plates 5 and preventing the blockage of the gaps between the adjacent middle comb plates 5 by the excessive silt.

As a preferred embodiment of the present invention, referring to fig. 1 to 6, 17 and 18, the side comb plate 4 comprises a rectangular steel plate, a comb-tooth-shaped structure 4-2 is arranged on one side of the upper part of the rectangular steel plate 4-1 close to the middle comb plate 5, and the comb-tooth-shaped structure 4-2 is W-shaped and is adapted to the W-shaped steel bar 21; the rectangular steel plate 4-1 is fixedly connected with the bottom cushion plate 6 and the first main beam 1.

As a preferred embodiment of the invention, a rubber strip is arranged in front of one side of the tooth-like structure 4-2 close to the middle comb plate 5.

Referring to fig. 1, 2, 4 and 16, as a preferred embodiment of the present invention, the steel attachment plate 3 is a steel plate having a comb-tooth structure at its edge; the comb tooth structure faces one side of the middle comb plate 5, and the thickness of the comb tooth structure is gradually reduced towards the direction of the middle comb plate 5; the end part of the comb tooth structure is provided with a second rubber strip 18.

As a preferred embodiment of the invention, the thickness of the comb structure towards one side edge of the middle comb plate 5 is half of the normal section of the steel butt strap 3.

Referring to fig. 1 to 3, 5 to 7, 10, 11 and 14, as a preferred embodiment of the present invention, the bottom plate 6 is a U-shaped steel plate 27, and the bottom edge of the bottom plate 6 is fixed to the first main beam 1; the plurality of middle comb plates 5 are arranged on the bottom edge of the bottom base plate 6 and positioned between two wing edges of the bottom base plate 6; the lower end of the middle spiral shaft 13 is rotatably connected with the bottom edge of the bottom cushion plate 6; the bottom edge of the bottom cushion plate 6 is provided with a slide way 14 for the slide strip 8 to slide.

As a preferred embodiment of the present invention, referring to fig. 5 to 7, 11 and 14, the slide way 14 includes a slide groove 22 and a stopper 23 for limiting the slide bar 8, the slide groove 22 is adapted to the slide bar 8, and the slide groove 22 and the stopper 23 are welded to the bottom edge of the bottom plate 6; referring to fig. 8, the slide bar 8 is connected with the second main beam 2 through a semi-hoop 17.

In the invention, the first main beam 1 and the second main beam 2 are the end parts of two couplings of a concrete bridge. The side comb plate 4 and the middle comb plate 5 work together to complete the adjustment of the width of the expansion joint.