CN113235491A

CN113235491A - Road guardrail and construction method thereof

Info

Publication number: CN113235491A
Application number: CN202110517130.2A
Authority: CN
Inventors: 郭志杰; 贺顶友; 赵三; 胡阳; 肖建武
Original assignee: Hunan Province Huaihua Highway Bridge Construction Corp
Current assignee: Hunan Province Huaihua Highway Bridge Construction Corp
Priority date: 2021-05-12
Filing date: 2021-05-12
Publication date: 2021-08-10
Anticipated expiration: 2041-05-12
Also published as: CN113235491B

Abstract

The application relates to a highway guardrail and a construction method thereof, belonging to the field of highway protection equipment, and comprising a guardrail body and a slide rail arranged on the surface of a road, wherein the upper surface of the slide rail is provided with a dovetail groove, and a dovetail block is connected in the dovetail groove in a sliding way and is used for being connected to the bottom end of the guardrail body; a plurality of fixing assemblies are arranged on the slide rail along the length direction of the slide rail, and each fixing assembly comprises an expansion cylinder, a connecting rod and an expansion block; the expansion cylinder is arranged on the lower surface of the sliding rail, and a through hole communicated with the interior of the expansion cylinder is formed in the bottom of the dovetail groove; the lower surface of the expansion cylinder is provided with a plurality of bending grooves; a placing groove is formed in the expansion cylinder, and the expansion block is embedded in the placing groove; the connecting rod is vertically connected above the expansion block and slides in the through hole and the expansion cylinder; the top end of the connecting rod is positioned in the placing groove; one side of the dovetail block in the sliding direction is a guide surface matched with the connecting rod. This application has the effect that improves road safety.

Description

Road guardrail and construction method thereof

Technical Field

The application relates to the field of highway protection equipment, in particular to a highway guardrail and a construction method thereof.

Background

At present, on expressways or urban roads, a highway guard rail is usually arranged in the middle of opposite lanes. The highway guard rail can effectively distinguish lanes, and the possibility that vehicles drive to opposite lanes is reduced. The highway guard rail can also reduce the possibility of accidents caused by pedestrians crossing roads. When the vehicle is out of control, the crash can be buffered through the guard rail, and the possibility of vehicle damage is reduced.

Chinese patent with grant publication number CN206873353U discloses a temporary municipal road construction protective guard, which comprises a protective guard body, wherein the bottom of the protective guard body is provided with a first baffle and a second baffle, the top of the second baffle is provided with a baffle rotary switch, the bottom of the protective guard body is in threaded connection with a base support, clamping plates are arranged on two sides of the protective guard body, and sponge layers are arranged inside the first baffle and the second baffle.

In view of the above-mentioned related art, the inventor believes that there is a defect that when a vehicle is out of control and is collided, the protective guard body is difficult to block the vehicle, which causes further danger to the lane on the other side.

Disclosure of Invention

In order to improve the safety of roads, the application provides a highway guardrail and a construction method thereof.

The utility model provides a highway guardrail adopts following technical scheme:

a highway guardrail comprises a guardrail body and a slide rail arranged on the surface of a road, wherein a dovetail groove is formed in the upper surface of the slide rail, a dovetail block is connected in the dovetail groove in a sliding mode, and the dovetail block is used for being connected to the bottom end of the guardrail body; a plurality of fixing assemblies are arranged on the slide rail along the length direction of the slide rail, and each fixing assembly comprises an expansion cylinder, a connecting rod and an expansion block; the expansion cylinder is arranged on the lower surface of the sliding rail, and a through hole communicated with the interior of the expansion cylinder is formed in the bottom of the dovetail groove; the lower surface of the expansion cylinder is provided with a plurality of bending grooves; a placing groove is formed in the expansion cylinder, and the expansion block is embedded in the placing groove; the connecting rod is vertically connected above the expansion block and slides in the through hole and the expansion cylinder; the top end of the connecting rod is positioned in the placing groove; one side of the sliding direction of the dovetail block is a guide surface matched with the connecting rod.

Through adopting above-mentioned technical scheme, make the deep hole in appointed position on the road, place the slide rail on the road, the inflation section of thick bamboo inserts in the deep hole. Insert the dovetail block in the dovetail of slide rail, promote the backplate body, the guardrail body drives the dovetail block and removes, and the spigot surface of dovetail block promotes the connecting rod and makes the connecting rod move down, and the connecting rod drives the inflation piece and moves down. The expansion block shifts out from the standing groove, because there is the setting in bending groove, the bottom that the expansion block promoted an expansion cylinder is buckled and outwards is kept away from, and the bottom of an expansion cylinder produces the inflation and supports tight deep hole, makes slide rail and road fixed. The dovetail block is also positioned in the dovetail groove of the slide rail, so that the possibility that the guardrail body is separated from the slide rail is reduced, the structural strength is improved, the possibility that the guardrail body is separated from the ground when a vehicle is impacted is reduced, the possibility of vehicle interception is improved, and the road safety is improved.

Optionally, the through-hole in-connection has the fender ring, one section cover that the connecting rod is located under the fender ring is equipped with first extension spring, first extension spring's top is connected with the fender ring, and the bottom is connected with the top of inflation piece.

Through adopting above-mentioned technical scheme, when need not use the guardrail, break away from the dovetail of dovetail piece and slide rail, separate guardrail body and slide rail. The connecting rod loses in the spacing back of dovetail piece is pulled back the standing groove under first extension spring's effect, and the manual work can take off the slide rail from ground this moment, and an inflation section of thick bamboo breaks away from with the deep hole.

Optionally, the top end of the connecting rod is arranged in an inclined plane, and the inclined plane is parallel to the guide surface.

Through adopting above-mentioned technical scheme, when the forked tail piece promoted the connecting rod with the inclined plane cooperation of connecting rod, the connecting rod moved down under the cooperation on spigot surface and inclined plane. The smooth degree of downward movement when the connecting rod contacts with the dovetail block is increased by the inclined surface.

Optionally, the outer peripheral wall of connecting rod has vertically seted up the spout, the internal perisporium that keeps off the ring is fixed with the fixed block, the fixed block slides in the spout.

Through adopting above-mentioned technical scheme, through when the connecting rod slides, through the cooperation of fixed block and spout, the removal of restriction connecting rod reduces connecting rod pivoted possibility, reduces the inclined plane and does not improve the stability of structure towards the possibility of dovetail piece.

Optionally, the baffle ring is in threaded connection with the sliding rail.

Through adopting above-mentioned technical scheme, when first extension spring, inflation piece damaged, rotate to keep off the ring and break away from the back with the slide rail, can take off connecting rod, inflation piece, first extension spring and change, make things convenient for manual maintenance.

Optionally, a screw is vertically arranged on the upper surface of the dovetail block, and the guardrail body comprises two upright posts and a cross rod which is positioned between and connects the two upright posts; the dovetail block is provided with a plurality of corresponding quantity of stand, the bottom and the screw rod threaded connection of stand.

Through adopting above-mentioned technical scheme, when the forked tail piece is located the dovetail, can rotate the forked tail piece and separate screw rod and stand, change or maintain the forked tail piece, reduce the possibility of whole change guardrail body, practice thrift the cost.

Optionally, the bottom of the stand is penetrated to establish and has an inserted bar in sliding connection, the slot that supplies the inserted bar to peg graft is seted up to the upper surface of slide rail, the top of inserted bar is fixed with the backup pad, set up in the stand and supply the backup pad gliding chamber that holds from top to bottom. And one vertical side wall of the upright post is provided with an operation groove communicated with the accommodating cavity.

Through adopting above-mentioned technical scheme, after the forked tail piece with the connecting rod butt, the inserted bar is located the top of slot, and the inserted bar inserts the slot under the effect of gravity, fixes the relative position between guardrail body and the slide rail, improves the position between guardrail body and the slide rail, has improved road safety. When the guardrail needs to be dismantled, the support plate is manually stirred through the operation groove to separate the inserted rod from the slot, and then the guardrail body can be moved.

Optionally, a glass column is arranged in the accommodating cavity below the supporting plate; when the lower surface of the inserted rod is flush with the lower surface of the upright post, the upper surface of the glass post is abutted against the lower surface of the supporting plate, and the lower surface of the glass post is supported on the inner bottom wall of the accommodating cavity; the lower surface of backup pad is provided with vertical second extension spring, the lower surface of backup pad is fixed in on the top of second extension spring, and the bottom mounting is in the interior diapire that holds the chamber.

Through adopting above-mentioned technical scheme, the backup pad is supported by the glass post under the natural state, reduces the possibility that need stir the backup pad when taking out the guardrail body from the slide rail, makes things convenient for manual operation. When the vehicle strikes the guardrail body, the glass post is broken, orders about the bracing piece with the downward pulling of backup pad and inserts the slot under extension spring's effect, accomplishes the fixed of guardrail body and slide rail, improves the security of road.

Optionally, a placing opening for taking out the dovetail block is formed in the upper surface of the slide rail between the two fixing assemblies.

By adopting the technical scheme, the dovetail block is conveniently and manually taken out through the arrangement of the dovetail block, and the manual operation is convenient.

Second aspect the application provides a construction method of highway guardrail adopts following technical scheme:

s100, a plurality of deep holes are formed in the positions, corresponding to the expansion cylinders in the sliding rail, of the upper surface of the road;

s200, placing the slide rail on the ground, and inserting the expansion cylinder into the deep hole at the corresponding position;

s300, connecting the upright post in the guardrail body with the screw thread of the dovetail block;

s400, inserting the dovetail block into the dovetail groove through the placing opening, pushing the dovetail block, and pushing the connecting column by the guide surface of the dovetail block to drive the connecting column to abut against the lower side of the dovetail block.

In summary, the present application includes at least one of the following beneficial technical effects:

1. the dovetail block is positioned in the dovetail groove of the slide rail, so that the possibility of separation of the guardrail body from the slide rail is reduced, the structural strength is improved, the possibility of separation of the guardrail body from the ground during vehicle collision is reduced, the possibility of vehicle interception is improved, and the road safety is improved;

2. when the guardrail is not needed, the dovetail block is separated from the dovetail groove of the slide rail, and the guardrail body is separated from the slide rail. After the connecting rod loses the limit of the dovetail block, the connecting rod is pulled back into the placing groove under the action of the first extension spring, at the moment, the sliding rail can be taken down from the ground manually, and the expansion cylinder is separated from the deep hole;

3. through when the connecting rod slides, through the cooperation of fixed block and spout, the removal of restriction connecting rod reduces the connecting rod pivoted possibility, reduces the inclined plane and does not improve the stability of structure towards the possibility of dovetail piece.

Drawings

Fig. 1 is a schematic view of the overall structure of a road guardrail according to embodiment 1 of the present application;

FIG. 2 is a schematic view, partly in section, of a road barrier of the type shown in FIG. 1;

FIG. 3 is an enlarged schematic view of portion A shown in FIG. 2;

fig. 4 is a flowchart of a construction method of a road guardrail according to an embodiment of the present application.

Description of reference numerals: 1. a slide rail; 2. a dovetail groove; 3. a dovetail block; 31. a guide surface; 4. a guardrail body; 41. a column; 42. a cross bar; 5. a fixing assembly; 51. an expansion cylinder; 511. bending the groove; 52. an expansion block; 53. a connecting rod; 531. a bevel; 6. a baffle ring; 7. a fixed block; 8. a chute; 9. a first extension spring; 10. a placement groove; 11. a screw; 12. a threaded hole; 13. inserting a rod; 14. a slot; 15. an accommodating chamber; 16. a support plate; 17. an operation slot; 18. a glass column; 19. a second extension spring; 20. the mouth is placed.

Detailed Description

The present application is described in further detail below with reference to the accompanying drawings.

The embodiment of the application discloses a road guardrail and a construction method thereof.

Example 1

Referring to fig. 1 and 2, including guardrail body 4 with set up in subaerial slide rail 1, slide rail 1 is the setting of horizontal rectangle pole, dovetail 2 has been seted up along the length direction of self to the upper surface of slide rail 1, and the length direction of dovetail 2 runs through the both ends of slide rail 1. A plurality of dovetail blocks 3 are connected in the dovetail grooves 2 of the slide rail 1 in a sliding way. The guardrail plate body comprises two upright columns 41 which are vertically arranged, a cross rod 42 is arranged between the two upright columns 41, and two ends of the cross rod 42 are perpendicularly welded with the side walls of the two upright columns 41 which are close to each other. The bottom end of the post 41 is connected to the dovetail block 3. Inserting the dovetail block 3 into the dovetail groove 2, connecting the slide rail 1 body with the slide rail 1, and connecting the slide rail 1 with the ground.

Referring to fig. 1 and 2, the two posts 41 in the guardrail body 4 are at the same distance. A plurality of guardrail bodies 4 can be connected to one slide rail 1. A plurality of fixing assemblies 5 are uniformly arranged on the sliding rail 1 along the length direction of the sliding rail, and the distance between the two fixing assemblies 5 is equal to the distance between the two dovetail blocks 3. The fixing component 5 comprises an expansion cylinder 51 vertically welded on the lower surface of the sliding rail 1, the groove bottom of the dovetail groove 2 vertically penetrates through a through hole with the same inner diameter as that of the expansion cylinder 51, and the through hole is coaxial with the expansion cylinder 51. A deep hole corresponding to the expansion cylinder 51 is formed in the road, and the diameter of the deep hole is the same as the outer diameter of the expansion cylinder 51. The slide rail 1 is attached to the ground, and the expansion cylinder 51 is inserted into the deep hole at the corresponding position.

Referring to fig. 2 and 3, the circumferential wall of the lower surface of the expansion cylinder 51 is provided with a plurality of bending grooves 511 along the radial direction of the expansion cylinder 51, the bending grooves 511 penetrate through the inner side and the outer side of the expansion cylinder 51, and the number of the bending grooves 511 is four in the present embodiment. The end of the expansion tube 51 where the bent groove 511 is formed can be bent inward or outward.

Referring to fig. 2 and 3, an expansion block 52 is provided in the expansion cylinder 51, and the expansion block 52 has an inverted circular truncated cone shape. The expansion block 52 is disposed coaxially with the expansion cylinder 51, and the diameter of the upper surface of the expansion block 52 is larger than the inner diameter of the expansion cylinder 51 and smaller than the major diameter of the expansion cylinder 51. The diameter of the lower surface of the expansion block 52 is smaller than the inner diameter of the expansion cylinder 51. The expansion cylinder 51 is provided with a placing groove 10 for the expansion block 52 to be embedded, and when the expansion block 52 is embedded in the placing groove 10, the expansion block 52 is positioned at the bottom end of the upper surface of the avoiding groove. The expansion block 52 is embedded in the placing groove 10 in a natural state.

Referring to fig. 2 and 3, a cylindrical connecting rod 53 is coaxially welded to the upper surface of the expansion block 52. When the expansion block 52 is fitted in the placement groove 10, the top end of the connecting rod 53 is higher than the groove bottom of the relief groove and lower than the upper surface of the slide bar. The through hole of the slide rail 1 is coaxially and threadedly connected with a baffle ring 6, and the connecting rod 53 is slidably connected with the inner peripheral wall of the baffle ring 6. When the connecting rod 53 is pushed downwards, the connecting rod 53 drives the expansion block 52 to move downwards and separate from the placing groove 10, and the peripheral wall of the expansion block 52 pushes a section of the expansion cylinder 51 located in the bending groove 511 to bend outwards.

Referring to fig. 2 and 3, a rectangular fixing block 7 is welded to an inner circumferential wall of the baffle ring 6. The outer peripheral wall of the connecting rod 53 is provided with a chute 8 for the fixed block 7 to slide along the vertical direction. When the connecting rod 53 moves vertically, the fixed block 7 slides in the slide groove 8.

Referring to fig. 2 and 3, a section of the connecting rod 53 located below the baffle ring 6 is sleeved with a first extension spring 9, the top end of the first extension spring 9 is welded to the lower surface of the baffle ring 6, and the end of the first extension spring 9 is welded to the top end of the expansion block 52. When the connecting rod 53 is not subjected to an external force, the first extension spring 9 pulls the expansion block 52 upward, so that the expansion block 52 enters the placing groove 10 again.

Referring to fig. 2 and 3, one side wall of the dovetail block 3, which is vertical and perpendicular to the sliding direction, is a guide surface 31 that is engaged with the connecting rod 53. The guide surface 31 is inclined from bottom to top to a side away from the dovetail block 3. The top surface of the connecting rod 53 is provided as a slope 531, and the slope 531 is parallel to the guide surface 31 of the dovetail block 3. The dovetail block 3 slides in the dovetail groove 2, and when the dovetail block 3 contacts the connecting rod 53, the guide surface 31 engages with the inclined surface 531 of the connecting rod 53 and pushes the connecting rod 53 to move vertically downward.

Referring to fig. 2 and 3, a screw 11 is vertically welded on the upper surface of the dovetail block 3, a threaded hole 12 is vertically formed in the lower surface of the upright post 41, and the screw 11 is inserted into and screwed into the threaded hole 12 of the upright post 41. The dovetail block 3 can be detached from the upright post 41 by rotating the dovetail block 3.

Referring to fig. 2 and 3, the bottom end of the upright post 41 is vertically inserted and slid with four insertion rods 13, two insertion rods 13 are located on two sides of the dovetail groove 2, and the upper surface of the slide rail 1 located on two sides of the dovetail groove 2 is respectively provided with slots 14 for insertion of the insertion rods 13. When the inserting rod 13 is inserted into the slot 14, the relative position between the upright 41 and the sliding rail 1 is fixed by the inserting rod 13.

Referring to fig. 2 and 3, a rectangular receiving cavity 15 is formed in the column 41. The holding cavity 15 is internally provided with a horizontal rectangular supporting plate 16, the corner of the lower surface of the supporting plate 16 is welded with the top end of the inserted link 13, one vertical side wall of the upright column 41 is provided with an operation groove 17 communicated with the holding cavity 15, and the supporting plate 16 can slide in the holding cavity 15. The human hand pushes the support plate 16 and the insert rod 13 to move upward through the operation slot 17 with the finger.

Referring to fig. 2 and 3, the receiving chamber 15 is internally provided with a vertical cylindrical glass column 18, and the glass column 18 is located below the support plate 16. The upper surface of the glass column 18 abuts against the lower surface of the support plate 16, and when the lower surface is supported by the inner bottom wall of the accommodating chamber 15, the lower surface of the insert rod 13 is flush with the lower surface of the upright column 41 and is separated from the slot 14. When the guardrail body 4 is hit by a car, the glass column 18 is broken and the insert rod 13 is inserted into the insert groove 14 under the action of gravity.

Referring to fig. 2 and 3, a vertical second extension spring 19 is disposed on the lower surface of the support plate 16, the second extension spring 19 is sleeved on the glass column 18, the bottom end of the second extension spring 19 is welded to the lower surface of the support plate 16, and the bottom end of the second extension spring 19 is welded to the inner bottom wall of the accommodating chamber 15. When the glass column 18 is broken, the support plate 16 and the insert rod 13 are moved downward by the second tension spring 19 and inserted into the insertion groove 14.

Referring to fig. 2 and 3, a placing opening 20 for taking out the dovetail block 3 is formed in the upper surface of the slide rail 1 between the two fixing assemblies 5, and the cross section of the placing opening 20 is rectangular and is communicated with the dovetail groove 2. The dovetail block 3 can be placed in the slide rail 1 through the placing opening 20.

The implementation principle of this application embodiment road guardrail does: and drilling a deep hole corresponding to the expansion cylinder 51 on the ground, placing the slide rail 1 on the ground, and inserting the expansion cylinder 51 into the deep hole at the corresponding position.

The screw 11 on the dovetail block 3 is connected with the screw hole 12 on the upright post 41 by screw thread, and the dovetail block 3 is put into the dovetail groove 2 of the slide rail 1 from the placing opening 20 and slides along the dovetail groove 2.

The guide surface 31 of the dovetail block 3 is engaged with the inclined surface 531 of the coupling pipe to push the coupling rod 53 to move downward, and the expansion block 52 is pushed by the coupling rod 53 to be disengaged from the inside of the standing groove 10 and to move downward. Under the extrusion of the inclined surface 531 on the expansion block 52, the part of the expansion cylinder 51 provided with the bending groove 511 is deformed and bent outwards and is pressed against the deep hole of the road.

When the guardrail body 4 is impacted by a vehicle, the glass column 18 is broken, the second tension spring 19 pulls the support plate 16 and the insert rod 13 to move downwards, and the insert rod 13 is inserted into the slot 14.

Example 2

Referring to fig. 4, a construction method of a highway barrier includes the steps of:

s100, a plurality of deep holes are formed in the road upper surface corresponding to the positions of the expansion cylinders 51 in the slide rail 1;

s200, placing the slide rail 1 on the ground, and inserting the expansion cylinder 51 into the deep hole at the corresponding position;

s300, connecting the threaded hole 12 in the upright post 41 in the guardrail body 4 with the screw rod 11 of the dovetail block 3 in a threaded manner;

s301, moving the support plate 16 upwards, and placing the glass column 18 below the support plate 16;

s400, inserting the dovetail block 3 into the dovetail groove 2 through the placing opening 20;

s401, pushing the dovetail block 3, wherein the guide surface 31 of the dovetail block 3 pushes the connecting column to drive the connecting column to abut against the lower side of the dovetail block 3.

The above embodiments are preferred embodiments of the present application, and the protection scope of the present application is not limited by the above embodiments, so: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.

Claims

1. The utility model provides a highway guardrail, includes guardrail body (4), its characterized in that: the guardrail comprises a guardrail body (4) and is characterized by further comprising a sliding rail (1) arranged on the surface of a road, wherein a dovetail groove (2) is formed in the upper surface of the sliding rail (1), a dovetail block (3) is connected in the dovetail groove (2) in a sliding mode, and the dovetail block (3) is used for being connected to the bottom end of the guardrail body (4); a plurality of fixing assemblies (5) are arranged on the sliding rail (1) along the length direction of the sliding rail (1), and each fixing assembly (5) comprises an expansion cylinder (51), a connecting rod (53) and an expansion block (52); the expansion cylinder (51) is arranged on the lower surface of the sliding rail (1), and a through hole communicated with the interior of the expansion cylinder (51) is formed in the bottom of the dovetail groove (2); the lower surface of the expansion cylinder (51) is provided with a plurality of bending grooves (511); a placing groove (10) is formed in the expansion cylinder (51), and the expansion block (52) is embedded in the placing groove (10); the connecting rod (53) is vertically connected above the expansion block (52) and slides in the through hole and the expansion cylinder (51); the top end of the connecting rod (53) is positioned in the placing groove (10); one side of the sliding direction of the dovetail block (3) is a guide surface (31) matched with the connecting rod (53).

2. A road guardrail as claimed in claim 1, wherein: the through-hole in-connection keeps off ring (6), one section cover that connecting rod (53) are located under keeping off ring (6) is equipped with first extension spring (9), the top and the fender ring (6) of first extension spring (9) are connected, and the bottom is connected with the top of inflation piece (52).

3. A road guardrail as claimed in claim 2, wherein: the top end of the connecting rod (53) is arranged in a slope (531), and the slope (531) is parallel to the guide surface (31).

4. A road guardrail as claimed in claim 3, wherein: the outer peripheral wall of connecting rod (53) has vertically seted up spout (8), the internal perisporium of fender ring (6) is fixed with fixed block (7), fixed block (7) slide in spout (8).

5. A road guardrail as claimed in claim 4, wherein: the baffle ring (6) is in threaded connection with the sliding rail (1).

6. A road guardrail as claimed in claim 1, wherein: the upper surface of the dovetail block (3) is vertically provided with a screw (11), and the guardrail body (4) comprises two upright posts (41) and a cross rod (42) which is positioned between the two upright posts (41) and connects the two upright posts (41); the dovetail blocks (3) are provided with a plurality of corresponding upright columns (41), and the bottom ends of the upright columns (41) are in threaded connection with the screw rods (11).

7. A road guardrail as claimed in claim 6, wherein: the bottom end of the upright post (41) penetrates through and is connected with an insertion rod (13) in a sliding mode, an insertion groove (14) for inserting the insertion rod (13) is formed in the upper surface of the sliding rail (1), a supporting plate (16) is fixed to the top end of the insertion rod (13), and an accommodating cavity (15) for the supporting plate (16) to slide up and down is formed in the upright post (41); an operation groove (17) communicated with the accommodating cavity (15) is formed in one vertical side wall of the upright column (41).

8. A road guardrail as claimed in claim 7, wherein: a glass column (18) is arranged in the accommodating cavity (15) and below the supporting plate (16); when the lower surface of the inserted rod (13) is flush with the lower surface of the upright post (41), the upper surface of the glass column (18) is abutted against the lower surface of the support plate (16), and the lower surface is supported on the inner bottom wall of the accommodating cavity (15); the lower surface of the supporting plate (16) is provided with a vertical second extension spring (19), the top end of the second extension spring (19) is fixed on the lower surface of the supporting plate (16), and the bottom end of the second extension spring is fixed on the inner bottom wall of the accommodating cavity (15).

9. A road guardrail as claimed in claim 1, wherein: the upper surface of the sliding rail (1) is positioned between the two fixed components (5) and is provided with a placing opening (20) for taking out the dovetail block (3).

10. A construction method of a road guardrail as claimed in any one of claims 1 to 9, wherein: the method comprises the following steps:

s100, a plurality of deep holes are formed in the positions, corresponding to the expansion cylinders (51) in the sliding rail (1), of the upper surface of the road;

s200, placing the slide rail (1) on the ground, and inserting the expansion cylinder (51) into the deep hole at the corresponding position;

s300, connecting the upright post (41) in the guardrail body (4) with the screw rod (11) of the dovetail block (3) in a threaded manner;

s400, inserting the dovetail block (3) into the dovetail groove (2) through the placing opening (20), pushing the dovetail block (3), and pushing the connecting column to enable the connecting column to abut against the lower portion of the dovetail block (3) by the aid of the guide surface (31) of the dovetail block (3).