A road widening and reinforcement structure

Abstract

This utility model discloses a road surface widening and reinforcement structure, relating to the field of highway construction technology. It includes a vertical stepped structure, a longitudinal cast-in-place layer, a longitudinal cast-in-place top layer, and crack-resistant components. The vertical stepped structure is formed by cutting the old road surface base layer with a longitudinal cutting machine to create a stepped overlapping interface, with the cutting depth consistent with the thickness of the corresponding structural layer. The longitudinal cast-in-place layer is placed at the joint between the old and new road surfaces in the cement-stabilized crushed stone lower base layer, and the longitudinal cast-in-place top layer is placed at the joint of the upper base layer with its top surface flush. The crack-resistant components include ribbed steel bars transversely embedded in the middle of the upper base layer, crack-resistant wire mesh laid at the bottom of the lower base layer, and crack-resistant tape covering the joint of the upper base layer. This utility model achieves a seamless connection between the old and new road surfaces, forming an integrated load-bearing system and significantly improving the road surface's load transfer capacity and deformation resistance.

Description

Technical Field

[0001] This utility model relates to the field of highway construction technology, and more specifically to a road surface widening and reinforcement structure. Background Technology

[0002] The development of my country's highway network has led to an increase in the reconstruction and expansion of existing roads. In road widening, the coordinated stress distribution between the new and old pavements and the interface treatment have become key constraints on project quality. Traditional sloping overlapping widening construction easily leads to stress concentration at the interface, causing longitudinal cracks. The different shrinkage coefficients of the new and old structural layers result in shrinkage cracks, and vehicle loads can cause reflective cracking, significantly shortening the lifespan of the widened pavement.

[0003] Existing joint treatment technologies have many shortcomings. The treatment of base layer overlap interfaces is often simplistic, such as roughening or sloping excavation, making it difficult to achieve effective mechanical interlocking. The interlayer crack-resistant system design is unsystematic, and single-layer crack-resistant materials cannot cope with differential deformation of structural layers. Poor transition treatment at the interface between new and old materials easily creates weak points, leading to interlayer slippage under the combined effects of temperature and traffic loads. These problems result in frequent early damage to widened pavements, and even structural failure. Utility Model Content

[0004] The purpose of this utility model is to provide a road widening and reinforcement structure in order to solve the above-mentioned technical problems.

[0005] The technical solution adopted by this utility model is as follows: a road surface widening and reinforcement structure, including a vertical step structure, a longitudinal cast-in-place layer, a longitudinal cast-in-place top layer, and crack-resistant components; the vertical step structure is formed by cutting the old road surface base layer with a longitudinal cutting machine to form a stepped overlapping interface, and the cutting depth is consistent with the thickness of the corresponding structural layer; the longitudinal cast-in-place layer is set at the joint of the cement-stabilized crushed stone lower base layer of the new and old road surfaces, and the longitudinal cast-in-place top layer is set at the joint of the upper base layer with its top surface flush; the crack-resistant components include ribbed steel bars inserted transversely in the middle of the upper base layer, crack-resistant steel wire mesh laid at the bottom of the lower base layer, and crack-resistant tape covering the joint of the upper base layer.

[0006] The vertical stepped structure forms a stepped interface, enhancing the interlocking force and integrity of the new and old road base layers; the longitudinal cast-in-place layer and the top layer are set in separate upper and lower layers to ensure the continuity of the joint between the new and old base layers and the flatness of the top surface; the crack-resistant components adopt multi-dimensional protection of steel bars, wire mesh and crack-resistant tape, effectively dispersing stress and inhibiting the generation of reflective cracks, thereby improving the durability and fatigue resistance of the road structure.

[0007] Preferably, the cutting depth of the vertical stepped structure matches the thickness of each structural layer, forming a stepped overlapping interface.

[0008] Preferably, both the longitudinal cast-in-place layer and the longitudinal cast-in-place pressure layer are formed by continuous casting of C30 concrete, and together with the base structure, they form an integral load-bearing system.

[0009] Preferably, the width of the longitudinal cast-in-place layer and the longitudinal cast-in-place pressure layer is 50-60cm.

[0010] Preferably, the ribbed steel bars are φ16 threaded steel bars with a length of 1.2-1.5 times the thickness of the base layer. They are arranged in both directions at a spacing of 80-100cm, with an implantation depth of not less than 25cm and the exposed ends are welded to the newly laid base layer steel mesh to form a rigid node.

[0011] Preferably, the width of the crack-resistant tape corresponds to the longitudinal cast-in-place top layer, and it is applied continuously and fully along the longitudinal joint.

[0012] Preferably, the crack-resistant steel wire mesh is formed by welding cold-drawn steel wire with a diameter of 3-5mm, and the mesh size is 10cm×10cm. When laying, it extends to the bottom of the newly laid base layer by 30-60cm.

[0013] Preferably, the surface of the longitudinal cast-in-place compacted top layer is provided with a composite crack-resistant structure, which includes a weather-resistant rubber strip embedded in the concrete surface and an SBS modified asphalt stress-absorbing layer covering the joint, wherein the top surface of the rubber strip is 2-3mm lower than the road surface elevation.

[0014] In summary, due to the adoption of the above technical solution, the beneficial effects of this utility model are:

[0015] 1. Enhance the overall structural integrity. The combination design of vertical stepped structure with longitudinal cast-in-place layer and top layer, through stepped overlapping interface and continuous pouring process (C30 concrete), achieves seamless connection between new and old pavement, forming an overall stress system, which significantly improves the load transfer capacity and deformation resistance of the pavement.

[0016] 2. Highly efficient crack resistance and multi-dimensional protection of crack-resistant components: Ribbed steel bars (φ16 threaded steel) are embedded in the middle of the base layer to improve tensile strength; the bottom crack-resistant steel wire mesh inhibits the expansion of cracks at the bottom of the base layer; the surface crack-resistant tape covers the joints to block reflective cracks, forming a "three-dimensional crack-resistant mesh" that effectively delays the generation and extension of cracks.

[0017] 3. By integrating interface strengthening, material performance optimization and crack-resistant technology, pavement damage caused by joint cracking and water damage is significantly reduced, road service life is extended, and the total life cycle maintenance cost is reduced. Attached Figure Description

[0018] This utility model will be described by way of example and with reference to the accompanying drawings, wherein:

[0019] Figure 1 This is a schematic diagram of the cross-sectional structure of this utility model;

[0020] The markings in the diagram are: 1-Vertical stepped structure, 2-Crack-resistant steel wire mesh, 3-Longitudinal cast-in-place layer, 4-Longitudinal cast-in-place top layer, 5-Ribbonded steel bar, 6-Crack-resistant tape. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can typically be arranged and designed in various different configurations.

[0022] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0023] In one embodiment of this utility model, such as Figure 1 As shown, this embodiment provides a pavement widening and reinforcement structure, including a vertical step structure 1, a longitudinal cast-in-place layer 3, a longitudinal cast-in-place top layer 4, and crack-resistant components. The vertical step structure 1 is formed by cutting the old pavement base layer with a longitudinal cutting machine to create a stepped overlapping interface, with the cutting depth consistent with the thickness of the corresponding structural layer. The longitudinal cast-in-place layer 3 is set at the joint of the cement-stabilized crushed stone lower base layer of the new and old pavements, and the longitudinal cast-in-place top layer 4 is set at the joint of the upper base layer with its top surface flush. The crack-resistant components include ribbed steel bars 5 transversely embedded in the middle of the upper base layer, crack-resistant wire mesh 2 laid at the bottom of the lower base layer, and crack-resistant tape 6 covering the joint of the upper base layer. The stepped overlapping interface formed by the vertical step structure 1 enhances the interlocking force and integrity of the new and old pavement base layers. The longitudinal cast-in-place layer 3 and the top layer are set in upper and lower layers to ensure the continuity and top surface flatness at the joint of the new and old base layers. The crack-resistant components adopt multi-dimensional protection with steel bars, wire mesh, and crack-resistant tape 6, effectively dispersing stress and inhibiting the generation of reflective cracks, thereby improving the durability and fatigue resistance of the pavement structure.

[0024] Specifically, the old road base layer is first treated by using a high-precision longitudinal cutting machine to make vertical cuts along the edge of the old road base layer. The cutting depth is consistent with the thickness of the structural layer to be reinforced (e.g., 20cm for the lower base layer and 18cm for the upper base layer), forming a stepped overlap interface. Each step is ≥30cm wide, ensuring that there is no loose material on the interface between the old and new base layers. After cutting, the interface is cleaned, rinsed with a high-pressure water gun, and an interface agent (such as epoxy resin) is applied to enhance the bonding performance. Then, the longitudinal cast-in-place layer 3 is constructed, and crack-resistant steel wire mesh 2 (specification: Φ5@10×10cm) is laid at the bottom of the joint. The overlap length of the mesh is ≥15cm, and it is tied and fixed. In the middle of the upper base layer (9cm from the top surface), holes are drilled in both directions at intervals of 80-100cm, with a hole diameter of 20mm and a depth of ≥25cm. Five Φ16 ribbed steel bars are implanted, with an exposed length ≥15cm. Reinforcing adhesive is injected into the holes for fixation. The exposed ends are welded to the newly laid base layer steel mesh (Φ12@15×15cm) to form a rigid joint. C30 concrete is poured, compacted using an immersion vibrator, and simultaneously vibrated and leveled. A curing agent is sprayed before final setting to ensure seamless connection with the existing base layer. Finally, crack-resistant tape 6 is applied. After the top layer reaches the required strength, the joint surface is cleaned and a special primer is applied. Crack-resistant tape 6 (50-60cm wide, ≥2mm thick) is fully applied along the longitudinal joint, using a roller to remove air bubbles, and the edges are heat-sealed to form a continuous waterproof and crack-resistant layer.

[0025] In another embodiment of this utility model, the cutting depth of the vertical step structure 1 is matched with the thickness of each structural layer to form a stepped overlapping interface. The strict matching of the cutting depth with the thickness of each structural layer avoids misalignment or stress concentration between the old and new base layers due to deviations in step dimensions, ensuring uniform stress distribution at the stepped overlapping interface and further optimizing the collaborative bearing capacity of the old and new road surfaces.

[0026] In another embodiment of this utility model, both the longitudinal cast-in-place layer 3 and the longitudinal cast-in-place top layer 4 are formed by continuous casting of C30 concrete, and together with the base structure, they form an integral load-bearing system. The use of continuous C30 concrete casting eliminates the weak joint problem of traditional layered construction, enabling the cast-in-place layer and the base layer to form a seamless integral load-bearing system, significantly improving the flexural tensile strength and shear resistance of the joint area.

[0027] In another embodiment of this utility model, the width of the longitudinal cast-in-place layer 3 and the longitudinal cast-in-place top layer 4 is 50-60cm. Limiting the width of the cast-in-place layer and the top layer to 50-60cm ensures sufficient load transfer area while avoiding material waste, balancing economy and structural stability, and ensuring a continuous and effective load transfer path between the old and new road surfaces.

[0028] In another embodiment of this utility model, the ribbed steel bar 5 is a φ16 threaded steel bar with a length of 1.2-1.5 times the thickness of the base layer. It is arranged bidirectionally at intervals of 80-100cm, with an insertion depth of not less than 25cm, and the exposed end is welded to the newly laid base layer steel mesh to form a rigid node. The high strength of the φ16 ribbed steel bar 5 and the reasonable spacing (80-100cm) form a three-dimensional constraint network, suppressing base layer shrinkage and cracking. The insertion depth and exposed welding design achieve rigid anchoring of the old and new structures, enhancing lateral tensile strength and preventing separation or misalignment at the joints.

[0029] In another embodiment of this utility model, the width of the crack-resistant tape 6 corresponds to the longitudinal cast-in-place top layer 4, and it is continuously and fully applied along the longitudinal joint. The crack-resistant tape 6 is applied with the same width as the top layer to form a continuous sealing layer, which prevents moisture from penetrating the joint and delays the expansion of thermal shrinkage cracks. Together with the internal crack-resistant components, it forms a three-dimensional crack prevention system that combines rigidity and flexibility.

[0030] In another embodiment of this utility model, the crack-resistant wire mesh is formed by welding cold-drawn steel wire with a diameter of 3-5mm, and the mesh size is 10cm×10cm. During installation, it extends 30-60cm to the bottom of the newly laid base layer. By extending the crack-resistant wire mesh to the bottom of the newly laid base layer by 30-60cm, the shear strength of the interface between the old and new base layers is significantly enhanced, inhibiting the propagation of longitudinal cracks caused by differential settlement or load transfer. The use of cold-drawn steel wire with a diameter of 3-5mm and a 10cm×10cm mesh size forms a uniform stress grid, effectively dispersing local stress generated by vehicle dynamic loads and reducing fatigue damage to the base layer. Increasing the mesh extension length to 60cm further covers weak areas of the new base layer, forming a continuous crack-resistant barrier, reducing the risk of water infiltration leading to base layer softening, and extending the service life of the pavement.

[0031] In another embodiment of this invention, the surface of the longitudinal cast-in-place compacted top layer is provided with a composite crack-resistant structure, comprising a weather-resistant rubber strip embedded in the concrete surface and an SBS modified asphalt stress-absorbing layer covering the joints, wherein the top surface of the rubber strip is 2-3 mm below the road surface elevation. The weather-resistant rubber strip absorbs the shrinkage stress of the concrete through elastic deformation, while the SBS modified asphalt stress-absorbing layer covers the joints, forming a flexible sealing layer. The combination of the two achieves dual protection of vertical deformation buffering and transverse crack prevention. The design of the rubber strip's top surface being 2-3 mm below the road surface avoids wear caused by vehicle impacts and provides deformation space to adapt to the expansion and contraction of concrete caused by temperature changes, preventing stress concentration at the joints. The composite structure effectively prevents rainwater from seeping into the joints, while the high and low temperature stability of the SBS modified asphalt layer reduces material aging, ensuring long-term crack prevention and reducing later maintenance costs.

[0032] The construction process of this utility model is as follows: cutting the old road → interface treatment → laying the anti-crack mesh of the lower base layer → inserting and welding the steel bars → pouring the cast-in-place layer → constructing the upper base layer capping → sealing with anti-crack tape 6 → curing and testing.

Claims

1. A road surface widening and reinforcement structure, characterized in that: It includes a vertical step structure (1), a longitudinal cast-in-place layer (3), a longitudinal cast-in-place top layer (4), and crack-resistant components; the vertical step structure (1) is formed by cutting the old road base layer with a longitudinal cutting machine to form a stepped overlapping interface, and the cutting depth is consistent with the thickness of the corresponding structural layer; the longitudinal cast-in-place layer (3) is set at the joint of the cement-stabilized crushed stone lower base layer of the new and old road surfaces, and the longitudinal cast-in-place top layer (4) is set at the joint of the upper base layer and the top surface is flush with it; the crack-resistant components include ribbed steel bars (5) that are horizontally implanted in the middle of the upper base layer, crack-resistant steel wire mesh (2) laid at the bottom of the lower base layer, and crack-resistant tape (6) covering the joint of the upper base layer.

2. The road widening and reinforcement structure according to claim 1, characterized in that: The cutting depth of the vertical stepped structure (1) is matched with the thickness of each structural layer to form a stepped overlapping interface.

3. The road surface widening and reinforcement structure according to claim 1, characterized in that: Both the longitudinal cast-in-place layer (3) and the longitudinal cast-in-place pressure layer (4) are formed by continuous casting of C30 concrete and form an integral load-bearing system with the base structure.

4. The road surface widening and reinforcement structure according to claim 3, characterized in that: The width of the longitudinal cast-in-place layer (3) and the longitudinal cast-in-place pressure layer (4) is 50-60cm.

5. The road surface widening and reinforcement structure according to claim 1, characterized in that: The ribbed steel bar (5) is made of φ16 threaded steel bar with a length of 1.2-1.5 times the thickness of the base layer. It is laid in both directions at a spacing of 80-100cm, with an implantation depth of not less than 25cm and the exposed end is welded to the newly laid base layer steel mesh to form a rigid node.

6. The road surface widening and reinforcement structure according to claim 1, characterized in that: The width of the crack-resistant tape (6) corresponds to the longitudinal cast-in-place top layer (4), and it is continuously applied along the longitudinal joint.

7. The road surface widening and reinforcement structure according to claim 1, characterized in that: The crack-resistant steel wire mesh (2) is formed by welding cold-drawn steel wire and extends to the bottom of the newly laid base layer by 30-60cm during installation.

8. The road surface widening and reinforcement structure according to claim 1, characterized in that: The longitudinal cast-in-place top layer (4) is provided with a composite crack-resistant structure, which includes a weather-resistant rubber strip embedded in the concrete surface and an SBS modified asphalt stress-absorbing layer covering the joint, wherein the top surface of the rubber strip is 2-3mm lower than the road surface elevation.

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