A gradient flexible splicing structure for tunnel pavement expansion joints and its construction method

Abstract

This invention relates to the field of tunnel pavement technology, and more particularly to a gradient flexible splicing structure for tunnel pavement expansion joints and its construction method. The structure includes a cement concrete base slab, a leveling layer, an asphalt lower layer, and an asphalt upper layer laid sequentially from bottom to top. A super-tough elastomer is placed in the first groove of the leveling layer, and the super-tough elastomer is connected to the leveling layer through a reinforcing structure. A polymer elastic-tough elastomer is placed in the second groove of the asphalt lower layer. The expansion joint of the cement concrete base slab extends to the bottom of the first groove, and the expansion joint is filled with asphalt sealant. The width of the polymer elastic-tough elastomer is greater than the width of the super-tough elastomer, and the portions of both extending beyond the width of the expansion joint are symmetrically arranged relative to the expansion joint, forming a gradient flexible splicing structure. This results in a gradient reduction in the deformation of the expansion joint, preventing pavement cracking. The asphalt upper layer is uniformly poured, avoiding direct contact between the elastomer and vehicles, extending the service life of the flexible splicing structure, and improving the durability and comfort of the pavement structure.

Description

Technical Field

[0001] This invention relates to the field of tunnel pavement technology, and in particular to a gradient flexible splicing structure for tunnel pavement deformation joints and its construction method. Background Technology

[0002] To meet the requirements of tunnel leveling layer pouring or structural deformation, expansion joints are generally set at intervals of about 30 to 60 meters. During tunnel paving construction, these joints are usually laid directly without any treatment. However, inspections have revealed that after 1 to 2 years of use, numerous reflective cracks appear at the expansion joint locations, severely affecting the performance of the asphalt surface layer and driving comfort. Treating expansion joints has become a major challenge in tunnel pavement construction.

[0003] Currently, the main method for dealing with expansion joint pavements is to lay a stress-absorbing layer such as waterproof membrane or hot-melt geotextile on top of the expansion joint. However, the stress-absorbing layer itself is relatively thin and cannot completely absorb all the deformation. The coordinated deformation between the pavement mixture and the stress-absorbing layer can easily lead to the breakage of the stress-absorbing layer. Reflective cracks can extend to the road surface in a short time, causing problems such as cracking and water seepage in tunnel pavement and mud pumping in the base layer. The final outcome of pavement cracking has not been completely changed. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a gradient flexible splicing structure for tunnel pavement deformation joints and its construction method, which effectively solves the problems in the background art.

[0005] To achieve the above objectives, the technical solution adopted by this invention is: a gradient flexible splicing structure for tunnel pavement deformation joints, comprising:

[0006] Cement concrete base slab;

[0007] A leveling layer is laid on the cement concrete base slab, and a first groove is opened on the upper surface of the leveling layer. An ultra-tough elastomer is placed in the first groove, and the ultra-tough elastomer is fixedly connected to the leveling layer by a reinforcing structure.

[0008] The asphalt base layer is laid on top of the leveling layer, and a second groove is provided directly above the first groove, and a polymer elastic toughness is provided in the second groove;

[0009] The asphalt top layer is laid on top of the asphalt bottom layer;

[0010] The cement concrete base plate has an expansion joint that extends to the bottom of the first groove and is filled with asphalt sealant.

[0011] The portions of the polymer elastomeric body and the ultra-tough elastomer that extend beyond the width of the deformation joint are symmetrically arranged relative to the deformation joint, and the width of the polymer elastomeric body is greater than the width of the ultra-tough elastomer, forming a gradient flexible splice from top to bottom.

[0012] Furthermore, the reinforcing structure includes two wing-shaped ribbed steel plates symmetrically arranged on both sides of the expansion joint;

[0013] The airfoil-shaped ribbed steel plate includes a first connecting plate and a second connecting plate that are fitted to the bottom and sidewall of the first groove, and the first connecting plate is arranged perpendicular to the second connecting plate;

[0014] The second connecting plate has a fixing rib on its outer side, which is embedded in the leveling layer. The first and second connecting plates are coated with epoxy resin and then fully coated with 30-80 mesh diamond grit for roughening.

[0015] Furthermore, the first connecting plate and the second connecting plate are provided with a plurality of shear studs on the contact surfaces with the ultra-tough elastomer.

[0016] Furthermore, the opposite edges of the two first connecting plates are flush with the edge of the expansion joint.

[0017] Furthermore, two portal steel bars are symmetrically arranged at the bottom of the first groove within the leveling layer relative to the deformation joint;

[0018] The tops of the two portal steel bars are attached to the reinforcing structure, and their bottoms extend into the cement concrete base slab to form a rigid base layer for tunnel pavement.

[0019] Furthermore, the lower part of the portal-shaped steel bar is embedded 5-10cm inside the cement concrete base plate.

[0020] Furthermore, the super-tough elastomer is formed by curing a super-tough resin binder. The super-tough resin binder is prepared by mixing component A and component B. Calculated by mass parts, component A includes 50-65 parts of polyether polyol, 1-7 parts of calcium oxide, 30-50 parts of diethanolamine, and 1-5 parts of defoamer; component B includes 50-70 parts of isocyanate, 5-10 parts of bisphenol A type epoxy resin, 1-4 parts of 1,4-butanediol, and 2-5 parts of organometallic catalyst.

[0021] Furthermore, the thickness of the polymer elastomeric body is the same as the thickness of the asphalt underlayer;

[0022] The polymer elastomeric body is located directly above the super-tough elastomer, and the two sides of the polymer elastomeric body extend 5 cm beyond the width of the super-tough elastomer.

[0023] Furthermore, the polymeric elastomeric material is formed by mixing single-size aggregates and polymeric asphalt at high temperature and then paving it, with a mass ratio of polymeric asphalt to graded aggregates of 30-40:100. The polymeric asphalt consists of 100 parts base asphalt, 6-10 parts SBS modifier, 5-10 parts polyethylene additive, 10-15 parts nano-grade rubber powder, 1-3 parts activator, 0.5-1.2 parts polyvinyl alcohol fiber, 6-10 parts composite synergist, and 5-10 parts smoke reducer.

[0024] The present invention also provides a construction method for the gradient flexible splicing structure of tunnel pavement deformation joint as described above, comprising the following steps:

[0025] S1: Precast or implant portal steel bars on the cement concrete bottom slab of the tunnel. The wing-shaped ribbed steel plate is connected and fixed to the portal steel bars by welding. The upper surface of the welded wing-shaped ribbed steel plate is flush with the upper surface of the leveling layer to be poured.

[0026] S2: Erect side formwork, pour cement concrete on both sides of the wing-shaped ribbed steel plate to form a leveling layer. The strength of the leveling layer must reach 80% of the design strength before the next step of construction can be carried out.

[0027] S3: Cast ultra-tough elastomer inside the airfoil ribbed steel plate until it is flush with the upper surface of the leveling layer, and cure for 12 hours.

[0028] S4: After laying the asphalt base layer, excavate in reverse directly above the expansion joint to form a second groove. The groove opening should be 5cm wider than the ultra-tough elastomer on both sides.

[0029] S5: Lay polymer elastic toughness in the second groove. The polymer elastic toughness is laid in two layers. After the laying is completed, it is rolled. The rolled polymer elastic toughness should be flush with the upper surface of the asphalt lower layer.

[0030] S6: Lay the asphalt surface layer;

[0031] S7: After the upper layer has been cured, traffic will be opened.

[0032] The beneficial effects of this invention are as follows: This invention utilizes the principle of modulus transition to achieve a gradient reduction in the expansion and contraction of deformation joints through the combination of different flexible materials, so that the asphalt surface layer is not affected by the expansion and contraction deformation of the deformation joint, thus extending the service life of the pavement at the tunnel deformation joint. Furthermore, the uniform paving on the upper layer ensures the integrity of the asphalt surface layer and the driving comfort.

[0033] This invention combines a double-layer elastomer and a flexible asphalt sealant structure to achieve a gradient reduction in the deformation of the expansion joint, thus preventing road surface cracking. The uniform pouring and paving of the asphalt surface layer improves the integrity and comfort of the road surface, while avoiding direct contact between the elastomer and vehicles, extending the service life of the flexible tunnel splice, avoiding the impact of the device's own deformation on the asphalt surface layer, and improving the durability and comfort of the tunnel expansion joint pavement structure.

[0034] The gradient deformation flexible splicing structure of tunnel pavement expansion joints of this invention has excellent traffic load-bearing capacity and excellent deformation resistance. It can effectively absorb the horizontal deformation caused by the expansion and contraction of concrete slabs and vehicle loads. By combining different flexible materials, the expansion and contraction of the expansion joint is reduced in a gradient manner, so that the asphalt surface layer is not affected by the expansion and contraction deformation of the expansion joint, thus extending the service life of the pavement at the tunnel expansion joint. Moreover, the uniform paving of the upper layer ensures the integrity and comfort of the pavement.

[0035] The asphalt pavement structure paving method of the present invention has a simple construction process and is more operable and convenient to construct compared with the materials and paving methods used in the prior art. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0037] Figure 1 This is a schematic diagram of the gradient flexible splicing structure of the tunnel pavement deformation joint in an embodiment of the present invention;

[0038] Figure 2 This is a schematic diagram of the reinforcing structure in an embodiment of the present invention;

[0039] Figure 3 This is a flowchart of the road structure construction method steps in an embodiment of the present invention.

[0040] Reference numerals: 1. Cement concrete base slab; 11. Expansion joint; 2. Leveling layer; 3. Lower asphalt layer; 4. Upper asphalt layer; 5. Ultra-tough elastomer; 6. Polymer elastomer; 7. Reinforcing structure; 71. Airfoil ribbed steel plate; 711. First connecting plate; 712. Second connecting plate; 713. Fixing rib; 714. Shear stud; 72. Portal reinforcement. Detailed Implementation

[0041] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0042] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0044] like Figures 1 to 2 The tunnel pavement deformation joint 11 shown is a gradient flexible splicing structure. This structure includes, from bottom to top, a cement concrete base slab 1, a leveling layer 2, an asphalt lower layer 3, and an asphalt upper layer 4. The leveling layer 2 is laid on top of the cement concrete base slab 1, and a first groove is formed on the upper surface of the leveling layer 2. A super-tough elastomer 5 is placed in the first groove, and the super-tough elastomer 5 is fixedly connected to the leveling layer 2 by a reinforcing structure 7. The asphalt lower layer 3 is laid on top of the leveling layer 2, and a second groove is provided directly above the first groove. A polymer elastic toughness body 6 is placed in the second groove. The asphalt upper layer 4 is laid on top of the asphalt lower layer 3. The combined use of the cement concrete base slab 1, the leveling layer 2, and the asphalt pavement layer gives the entire structure high strength and stability, enabling it to withstand the pressure of large traffic volumes and heavy vehicles. The super-tough elastomer 5 and the polymer elastic toughness body 6 placed on the leveling layer 2 can effectively absorb and disperse the vibration and impact force generated by vehicle travel, reduce stress concentration at the deformation joint 11, and thus improve the deformation resistance of the pavement.

[0045] The cement concrete base slab 1 has an expansion joint 11 extending to the bottom of the first groove. The expansion joint 11 is filled with asphalt sealant, which can effectively prevent water and dust from entering the gap and reduce road surface damage and corrosion. In addition, the polymer elastic tough body 6 and the ultra-tough elastomer 5 are symmetrically arranged on the left and right sides of the expansion joint 11, and the width of the polymer elastic tough body 6 is greater than the width of the ultra-tough elastomer 5, forming a gradient flexible splice from top to bottom.

[0046] In a preferred embodiment of the present invention, the leveling layer 2 and the super-tough elastomer 5 achieve integral paving through the synergistic effect of the reinforcing structure 7. The super-tough elastomer 5 is disposed on the upper surface of the leveling layer 2, extending the deformation joint 11 to the bottom of the super-tough elastomer 5, which can largely accommodate the displacement of the deformation joint 11. The polymer elastic-tough body 6 is located in the asphalt lower layer 3, connected to the super-tough elastomer 5 and the asphalt upper layer 4, and fills the deformation joint 11 below with asphalt sealant. The widths of the polymer elastic-tough body 6, the super-tough elastomer 5, and the asphalt sealant in the vertical direction are as follows from top to bottom: The deformation of the expansion joint 11 is reduced by combining the ultra-tough elastomer 5 with the polymer elastomer 6 and the asphalt sealant to form a gradient flexible splice. Through the double-layer elastomer and flexible asphalt sealant structure, the deformation of the expansion joint 11 is reduced in a gradient, avoiding road surface cracking. The asphalt surface layer 4 is uniformly poured and paved, which improves the integrity and comfort of the road surface. At the same time, it avoids direct contact between the elastomer and vehicles, extends the service life of the tunnel flexible splice, avoids the impact of the deformation of the splice structure itself on the asphalt surface layer, and improves the durability and comfort of the road surface structure of the tunnel expansion joint 11.

[0047] In a preferred embodiment of the present invention, the reinforcing structure 7 includes two airfoil-shaped ribbed steel plates 71 symmetrically arranged on both sides of the expansion joint 11; the airfoil-shaped ribbed steel plate 71 includes a first connecting plate 711 and a second connecting plate 712 that are attached to the bottom and sidewall of the first groove, the first connecting plate 711 being arranged perpendicular to the second connecting plate 712; a fixing rib 713 is provided on the outer side of the second connecting plate 712, and the fixing rib 713 is embedded in the leveling layer 2.

[0048] Specifically, the wing-shaped ribbed steel plate 71 is composed of two L-shaped steel plates symmetrically distributed on both sides of the expansion joint 11. It can effectively resist the stress concentration generated by the road surface and disperse it to the surrounding area, reducing structural deformation and damage. The first connecting plate 711 is set perpendicular to the second connecting plate 712. The surfaces of the first connecting plate 711 and the second connecting plate 712 are coated with epoxy resin and then fully coated with 30-80 mesh diamond grit for roughening treatment, which can increase the stability of the connection and make the connection between the wing-shaped ribbed steel plate 71 and the leveling layer 2 more solid, effectively preventing shearing and slippage at the expansion joint 11. The wing-shaped ribs are welded to the outer side of the second connecting plate 712, and the fixing ribs 713 are embedded in the leveling layer 2, providing additional support and fixing. This can increase the compaction effect of the leveling layer 2, reduce settlement and deformation, and maintain the flatness and stability of the road surface.

[0049] Based on the above embodiments, a plurality of shear studs 714 are provided on the mating surfaces of the first connecting plate 711 and the second connecting plate 712 and the ultra-tough elastomer 5.

[0050] Specifically, T-shaped shear studs 714 are welded to the inner sides of the first connecting plate 711 and the second connecting plate 712, with the ratio of side shear studs 714 to bottom shear studs 714 being 1:3. After welding, an epoxy resin coating is applied to the surface, with a coating amount of 0.4–0.6 kg / m². 2 Then, a 30-80 mesh diamond abrasive is applied, and after curing, a rough surface is formed. The shear studs 714 increase the shear resistance of the connection. When subjected to lateral force or shear stress, the shear studs 714 have the ability to absorb and transfer load, thereby reducing the shear stress concentration between the ultra-tough elastomer 5 and the leveling layer 2, and thus improving the shear strength of the structure.

[0051] During the pouring of the leveling layer 2, since part of the expansion joint 11 is located within the leveling layer 2, in order to ensure the stability of the expansion gap of the expansion joint 11 in the vertical direction, the relative edges of the two first connecting plates 711 are flush with the edge of the expansion joint 11. A template is erected inside the expansion joint 11, and the template is fixed to the edge of the expansion joint 11 by welding. Cement concrete is poured from both sides of the fixing rib 713 to form the leveling layer 2. After that, the erected template is removed, and asphalt sealant is poured along the gap between the two first connecting plates 711 of the expansion joint 11 until it is flush with the bottom surface of the wing-shaped ribbed steel plate 71. At this time, the first groove in the leveling layer 2 is formed. The asphalt sealant reduces the expansion of the expansion joint 11 and makes it less likely to cause edge chipping.

[0052] In a preferred embodiment of the present invention, two portal steel bars 72 are symmetrically arranged at the bottom of the first groove in the leveling layer 2 relative to the deformation joint 11; the top of the two portal steel bars 72 is attached to the reinforcing structure 7, and their bottom extends into the cement concrete base plate 1 to form a rigid base layer for tunnel pavement.

[0053] Specifically, the cement concrete base slab 1 is symmetrically arranged with an expansion joint 11 in the middle. Holes are drilled in the cement concrete base slab 1, and portal steel bars 72 are arranged at 10cm intervals and 5cm from the edge of the expansion joint 11. The portal steel bars 72 are symmetrically installed with sealant. A wing-shaped ribbed steel plate 71 is installed directly above the portal steel bars 72 by welding. Preferably, the lower part of the portal steel bars 72 is embedded 5-10cm into the cement concrete base slab 1. Through the arrangement of the wing-shaped ribs and the portal steel bars 72, the wing-shaped ribbed steel plate 71 and the leveling layer 2 form an integral whole, achieving synchronous deformation, which increases the stability and overall rigidity of the road surface. Furthermore, when paving the road surface, the portal steel bars 72 are pre-embedded in the leveling layer 2 and attached to the reinforcing structure 7, which can improve the accuracy and efficiency of construction and reduce the difficulty and cost of construction.

[0054] In a preferred embodiment of the present invention, the super-tough elastomer 5 is formed by curing a super-tough resin binder, with a thickness of 5-10 cm and a width of 30-40 cm. The super-tough resin binder is prepared by mixing component A and component B. Component A, by mass parts, includes 50 parts of polyether polyol, 1 part of calcium oxide, 30 parts of diethanolamine, and 1 part of defoamer; component B includes 50 parts of isocyanate, 5 parts of bisphenol A epoxy resin, 1 part of 1,4-butanediol, and 2 parts of organometallic catalyst.

[0055] In this invention, ultra-tough resin components A and B are mixed in a 1:1 ratio and poured into the airfoil-shaped ribbed steel plate 71 after 2 minutes, until flush with the upper edge of the airfoil-shaped ribbed steel plate 71. Shear studs 714 and surface roughening ensure a strong bond between the steel plate and the ultra-tough elastomer 5, forming a unified whole. The ultra-tough resin binder is designed to adapt to the deformation of the expansion joint 11, allowing the ultra-tough elastomer 5 to be stretched when the expansion joint 11 widens and compressed when the expansion joint 11 narrows. The above-mentioned mixing ratio meets the specific technical indicators shown in the table below after testing.

[0056] Table 1 Technical Specifications of Ultra-Tough Resin Cementitious Materials

[0057]

[0058] In this invention, the thickness of the polymer elastic toughness body 6 is the same as the thickness of the asphalt lower layer 3; and the polymer elastic toughness body 6 is located directly above the super-tough elastomer 5. The polymer elastic toughness body 6 extends 5cm beyond the super-tough elastomer 5 on both sides, which can increase the flexibility and elasticity of the pavement, distribute the load and reduce stress concentration, and provide an additional sealing and protective layer. Specifically, the asphalt lower layer 3 has a paving thickness of 60mm. The position of the super-tough elastomer 5 is marked on the asphalt lower layer 3. After widening the two sides by 5cm, a second groove is excavated in the lower layer. The polymer elastic toughness body 6 is poured into the second groove of the paving lower layer. The pouring should be 1-2cm higher than the groove opening. After cooling, a small road roller is used to compact it to be flush with the groove opening. After the polymer elastic toughness body 6 reaches the design strength, an asphalt upper layer 4 with a thickness of 40mm is laid on top of the asphalt lower layer 3.

[0059] In a preferred embodiment of the present invention, the polymer elastic toughness 6 is formed by mixing single-size aggregate and polymer asphalt at high temperature and then laying it. The mass ratio of polymer asphalt to graded aggregate is 30-40:100. Specifically, the single-size aggregate and polymer asphalt are mixed at 185°C in a ratio of 30:100 to form the polymer elastic toughness 6, which is then poured into the groove. The single-size aggregate is ordinary basalt crushed stone with a maximum particle size of 19mm. The aggregate gradation range is as follows: the passing rate of sieve with a sieve size of 16mm is 75%-80%, the passing rate of sieve with a sieve size of 13.2mm is 42%-50%, and the passing rate of sieve with a sieve size of 9.5mm is 10%-15%. The polymer asphalt is formed by sequentially adding and stirring 100 parts of base asphalt, 6 parts of SBS modifier, 5 parts of polyethylene additive, 10 parts of nano-grade rubber powder, 1 part of activator, 0.5 parts of polyvinyl alcohol fiber, 6 parts of composite synergist, and 5 parts of smoke reducer at 160℃. The specific technical indicators shown in the table below are met by setting the above proportions.

[0060] Table 2 Technical Specifications of Polymer Elastics and Toughnesses

[0061]

[0062] This invention also provides a construction method for a gradient flexible splicing structure for tunnel pavement expansion joints, such as... Figure 3 As shown, it includes the following steps:

[0063] S1: Precast or implant portal steel bars 72 on the cement concrete bottom slab 1 of the tunnel. The wing-shaped ribbed steel plate 71 is connected and fixed to the portal steel bars 72 by welding. The height of the upper surface of the welded wing-shaped ribbed steel plate 71 is flush with the upper surface of the leveling layer 2 that needs to be poured.

[0064] S2: Erect side formwork and pour cement concrete on both sides of the wing-shaped ribbed steel plate 71 to form leveling layer 2. The strength of leveling layer 2 must reach 80% of the design strength before the next step of construction can be carried out.

[0065] S3: Cast ultra-tough elastomer 5 inside the wing-shaped ribbed steel plate 71. Cast the ultra-tough elastomer 5 until it is flush with the upper surface of the leveling layer 2, and cure for 12 hours.

[0066] S4: After laying the asphalt base layer 3, excavate in reverse directly above the expansion joint 11 to form a second groove. The groove opening should be 5cm wider than the ultra-tough elastomer 5 on both sides.

[0067] S5: Lay polymer elastic toughness 6 in the second groove. The polymer elastic toughness 6 is laid in two layers. After the laying is completed, it is rolled. The rolled polymer elastic toughness 6 should be flush with the upper surface of the asphalt lower layer 3.

[0068] S6: Lay the asphalt surface layer 4.

[0069] S7: After the upper layer has been cured, traffic will be opened.

[0070] The gradient deformation flexible splicing structure of the tunnel pavement expansion joint 11 of this invention has excellent traffic load-bearing capacity and excellent deformation resistance. It can effectively absorb the horizontal and vertical deformation caused by the expansion and contraction of concrete slabs and vehicle loads. By combining different flexible materials, the expansion and contraction of the expansion joint 11 is reduced in a gradient manner, so that the asphalt surface layer is not affected by the expansion and contraction deformation of the expansion joint 11, thus extending the service life of the pavement at the tunnel expansion joint 11. Moreover, the uniform paving of the upper layer ensures the integrity and comfort of the pavement.

[0071] Those skilled in the art should understand that this invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to this invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A gradient flexible splicing structure for tunnel pavement deformation joints, characterized in that, include: Cement concrete base slab; A leveling layer is laid on the cement concrete base slab, and a first groove is opened on the upper surface of the leveling layer. An ultra-tough elastomer is placed in the first groove, and the ultra-tough elastomer is fixedly connected to the leveling layer by a reinforcing structure. The asphalt base layer is laid on top of the leveling layer, and a second groove is provided directly above the first groove, and a polymer elastic toughness is provided in the second groove; The asphalt top layer is laid on top of the asphalt bottom layer; The cement concrete base plate has an expansion joint that extends to the bottom of the first groove and is filled with asphalt sealant. The portions of the polymer elastomeric body and the ultra-tough elastomer that extend beyond the width of the deformation joint are symmetrically arranged relative to the deformation joint, and the width of the polymer elastomeric body is greater than the width of the ultra-tough elastomer, forming a gradient flexible splice body. The reinforcing structure includes two wing-shaped ribbed steel plates symmetrically arranged on both sides of the expansion joint; The airfoil-shaped ribbed steel plate includes a first connecting plate and a second connecting plate that are fitted to the bottom and sidewall of the first groove, and the first connecting plate is arranged perpendicular to the second connecting plate; The second connecting plate has a fixing rib on its outer mating surface, and the fixing rib is embedded in the leveling layer; The first connecting plate and the second connecting plate are provided with a plurality of shear studs on the contact surfaces with the ultra-tough elastomer; Two portal steel bars are symmetrically arranged at the bottom of the first groove within the leveling layer, relative to the deformation joint. The tops of the two portal steel bars are attached to the reinforcing structure, and their bottoms extend into the cement concrete base slab to form a rigid base layer for tunnel pavement. Asphalt sealant is poured along the expansion joint in the gap between the two first connecting plates until it is flush with the bottom surface of the wing-shaped ribbed steel plate. This forms the first groove in the leveling layer. After the asphalt lower layer is laid, the second groove is formed by excavating directly above the expansion joint.

2. The gradient flexible splicing structure for tunnel pavement deformation joints according to claim 1, characterized in that, The opposite edges of the two first connecting plates are flush with the edge of the expansion joint.

3. The gradient flexible splicing structure for tunnel pavement deformation joints according to claim 1, characterized in that, The lower part of the portal-shaped steel bar is inserted into the cement concrete base plate 5-10cm.

4. The gradient flexible splicing structure for tunnel pavement deformation joints according to claim 1, characterized in that, The ultra-tough elastomer is formed by curing an ultra-tough resin binder.

5. The gradient flexible splicing structure for tunnel pavement deformation joints according to claim 1, characterized in that, The thickness of the polymer elastic toughness is the same as the thickness of the asphalt underlayer; The polymer elastomeric body is located directly above the super-tough elastomer, and the two sides of the polymer elastomeric body extend 5 cm beyond the width of the super-tough elastomer.

6. The gradient flexible splicing structure for tunnel pavement deformation joints according to claim 1, characterized in that, The polymer elastomeric material is formed by mixing single-size aggregate and polymer asphalt at high temperature and then paving it. The mass ratio of polymer asphalt to graded aggregate is 30-40:

100.

7. A construction method for a gradient flexible splicing structure for tunnel pavement deformation joints as described in any one of claims 1-6, characterized in that, Includes the following steps: S1: Precast or implant portal steel bars on the cement concrete bottom slab of the tunnel. The wing-shaped ribbed steel plate is connected and fixed to the portal steel bars by welding. The upper surface of the welded wing-shaped ribbed steel plate is flush with the upper surface of the leveling layer to be poured. S2: Erect side formwork, pour cement concrete on both sides of the wing-shaped ribbed steel plate to form a leveling layer. The strength of the leveling layer must reach 80% of the design strength before the next step of construction can be carried out. S3: Cast ultra-tough elastomer inside the airfoil ribbed steel plate until it is flush with the upper surface of the leveling layer, and cure for 12 hours. S4: After laying the asphalt base layer, excavate in reverse directly above the expansion joint to form a second groove. The groove opening should be 5cm wider than the ultra-tough elastomer on both sides. S5: Lay polymer elastic toughness in the second groove. The polymer elastic toughness is laid in two layers. After the laying is completed, it is rolled. The rolled polymer elastic toughness should be flush with the upper surface of the asphalt lower layer. S6: Lay the asphalt surface layer; S7: After the upper layer has been cured, traffic will be opened.

Images