Rapid rural road hardened pavement construction method

Abstract

The invention relates to the technical field of road engineering, in particular to a rapid rural road hardened pavement construction method which comprises the following steps: S1, pretreatment of waste tires and manufacturing of grid units; s2, roadbed treatment and leveling layer construction; s3, on-site paving of the composite flexible stress release layer; s4, factory production of the precast concrete panel; s5, prefabricated slabs are assembled and laid on site; s6, joint treatment and surface sealing are conducted; and S7, maintaining and opening traffic. According to the invention, a four-stage anti-settlement structural system with roadbed point-like reinforcement, geogrid reinforcement, rubber grid stress release and prefabricated slab bottom anchoring is innovatively built, and each structural layer performs own functions and synergistically resists deformation, so that the adaptive capacity of the road to differential settlement is improved, and the service life of the road is prolonged. The stubborn problems that a traditional rural road is prone to plate breakage, cracking and subsidence are thoroughly solved from the structural design, and the service life of the road is prolonged.

Description

Technical Field

[0001] This invention relates to the field of road engineering technology, and in particular to a quick method for constructing hardened pavement for rural roads. Background Technology

[0002] The demand for hardened rural road surfaces is increasing. Hardened surfaces, due to their dustproof, waterproof, and durable characteristics, have become the main form of rural road construction. Rural roads are an important carrier for the transportation of goods and the travel of people in rural areas.

[0003] Traditional methods for constructing hardened rural roads often involve using cast-in-place concrete pavement or laying ordinary precast concrete blocks. In rural areas, the roadbed is mostly made of plain soil, which makes it difficult to control the compaction degree. In addition, some areas have weak foundations, which can easily lead to problems such as voids at the bottom of the slabs, broken pavement slabs, cracks, and subsidence under vehicle loads and natural settlement, affecting the service life of the road. Therefore, it is necessary to design a quick method for constructing hardened rural roads. Summary of the Invention

[0004] In order to overcome the shortcomings of the existing technology, the purpose of this invention is to provide a quick method for constructing hardened rural road surfaces.

[0005] The technical solution adopted in this invention is: a quick method for constructing hardened rural road surfaces, comprising the following steps: S1: Pre-treatment of waste tires and manufacturing of grid units. The waste tires are sorted and cut, the rubber strips are surface activated, and the grid sheets are woven and formed in sequence to obtain flexible stress-relieving grid sheets with elastic buffering and structural stability. S2: Subgrade treatment and leveling layer construction, which involves mechanically compacting and locally improving the subgrade to be constructed, laying a geosynthetic isolation layer, laying a reinforcement layer, and constructing a fine leveling layer to form a flat, stable, and deformation-resistant subgrade working surface; S3: On-site paving of the composite flexible stress relief layer, which involves laying and fixing the flexible stress relief grid sheet, filling and compacting the first layer of aggregate, filling and compacting the second layer of aggregate, and spraying the tack coat oil to form a composite flexible stress relief layer with a rubber skeleton and crushed stone filling. S4: The factory production of precast concrete panels involves the sequential preparation of high-precision steel molds, installation of double-layer steel mesh, pouring and vibration of high-grade concrete, standardized curing, demolding and stacking of finished products, resulting in precast concrete panels with hemispherical anchoring protrusions and hyperboloid lap joint structures. S5: On-site assembly and laying of precast slabs, in sequence completing precise laying layout, anchored laying of precast slabs, dynamic adjustment of road surface flatness, and standardized control of slab joints, to complete the assembly of the main road structure; S6: Joint treatment and surface sealing, which involves joint cleaning, application of interface agent, layered injection of modified sealant, laying of crack-resistant tape across the joint, and overall waterproof spraying of the road surface to construct a multi-layer waterproof and crack-resistant system. S7: Maintenance and opening to traffic. The initial closure maintenance after construction and the quality inspection of various road surface indicators are completed in sequence. After passing the inspection, the road is officially opened to traffic.

[0006] As a further description of the above technical solution: In step S1, the waste tire sorting and cutting involves removing damaged tires with severely exposed bead wires, punctures in the tire body, or cracks deeper than 2cm. The qualified tire treads are cut into rubber strips with a width of 3-8cm and a length of 15-30cm using CNC tire cutting equipment. The surface activation treatment of the rubber strips involves immersing the rubber strips completely in a silane coupling agent solution for 20-40 minutes, then removing them and placing them in a ventilated and cool place to air dry naturally for no less than 12 hours.

[0007] As a further description of the above technical solution: In step S1, the mesh sheet is woven using high-strength polyester fiber rope as the braiding reinforcement. The activated rubber strips are cross-woven with warp and weft. During the weaving process, a prestress of 0.5-1.0 MPa is applied to the rubber strips to keep them taut. The resulting flexible stress-relieving mesh sheet has a mesh size of 8cm×8cm to 15cm×15cm, a thickness of 5-10cm, a porosity of 30%-50%, and a single mesh sheet specification of 2m×3m or 1m×2m, which is suitable for the on-site construction work surface.

[0008] As a further description of the above technical solution: In step S2, the roadbed compaction is carried out by 18-20t road roller in layers, with each layer not exceeding 30cm in thickness. In local soft foundation sections, 30-50cm of soft soil layer is excavated and replaced with crushed stone soil. The geotextile isolation layer is 200-400g / ㎡ long-filament singed geotextile with an overlap width of not less than 20cm, and the overlap is bonded by hot melt. The reinforcement layer is a biaxial tensile plastic geogrid that matches the size of the mesh sheet. The leveling layer is 3-5cm thick clean stone chips, which are leveled using a screed and a level, and the surface flatness is controlled within ±1cm.

[0009] As a further description of the above technical solution: In step S3, the flexible stress-relieving mesh is laid in a staggered manner, with an overlap width of no less than 10cm between adjacent meshes. The overlap is tied with high-strength plastic cable ties every 20cm. The first layer of aggregate consists of hard crushed stone with a particle size of 2-4cm, and the filling thickness is 2 / 3 of the thickness of the flexible stress-relieving mesh. It is compacted using a plate vibrator at a frequency of 20-30Hz. The second layer of aggregate consists of stone chips with a particle size of 0.5-1cm mixed with 10%-20% grade 1 fly ash, and is filled to be flush with the surface of the flexible stress-relieving mesh. It is compacted at a frequency of 25-35Hz for 30-60 seconds. The tack coat is a slow-cracking emulsified asphalt tack coat, with a spraying dosage of 0.8-1.2kg / ㎡. After spraying, it naturally demulsifies and cures for no less than 4 hours.

[0010] As a further description of the above technical solution: In step S4, the bottom of the high-precision steel mold is provided with a quincunx-shaped arrangement of pits, which are used to form hemispherical protrusions with a diameter of 3-5cm and a height of 2-3cm. The center-to-center spacing of the pits is 10-15cm. The sides of the steel mold are provided with wavy curved forming blocks to form a hyperboloid lap structure. The diameter of the steel bars in the double-layer steel mesh is 6-8mm, the mesh size is 15cm×15cm, the spacing between the upper and lower mesh layers is 5-8cm, and the thickness of the protective layer is controlled at 2.5cm. The concrete is dry-hard concrete with a strength grade of C50 or above, and the slump is controlled at 3-5cm. An immersion vibrator is used in conjunction with a plate vibrator for layered vibration until the concrete surface is covered with slurry and free of air bubbles.

[0011] As a further description of the above technical solution: In step S4, the curing method is steam curing, which is divided into three stages: heating, constant temperature, and cooling. The heating rate is ≤10℃ / h, the constant temperature stage temperature is 50℃-60℃, the curing time is 8-12 hours, and the cooling rate is ≤15℃ / h. When demolding, the concrete strength reaches more than 75% of the design strength, and after demolding, curing continues until the design strength is reached.

[0012] As a further description of the above technical solution: In step S5, the laying and setting out are carried out using a total station and a chalk line to mark the road edge line, slab joint control line, and elevation control line, with the elevation error controlled within ±2mm. The precast slabs are laid using a small forklift for lifting, relying on their own weight to make the hemispherical protrusions on the bottom of the slabs embed into the surface pores of the composite flexible stress release layer by 3-5mm to form multi-point anchorage. The flatness is checked every 2m with a 3m straightedge, and uneven areas are leveled with additional stone chips, with a maximum deviation ≤3mm. The joint width between adjacent precast slabs is controlled within 5-8mm, and temporary fixing is done with plastic wedges, with the fixing point spacing not exceeding 50cm.

[0013] As a further description of the above technical solution: In step S6, the joint cleaning is performed by blowing with 0.5-0.8MPa high-pressure air and then cleaning with a wire brush to ensure that there is no floating dust, debris and water accumulation in the joint; the interface agent is a rubber asphalt interface agent, applied with a width of 3-5cm, applied evenly without omissions, and after surface drying, the sealant is injected; the sealant is a modified rubber asphalt sealant, heated to 160℃-180℃ to a fluid state, initially injected to a depth of 2-3mm below the board surface, cooled and shrunk for 30-60 minutes, and then injected a second time to be flush with the board surface; the crack-resistant tape is a 1.5-2.0mm thick high-performance self-adhesive crack-resistant tape, laid across the joint with a width of 10-15cm, and compacted from the center to both sides with a rubber mallet, without hollows or curling edges; the waterproof spray is a nano silane waterproof agent, applied by mist spraying, with a dosage of 0.2-0.3kg / ㎡, sprayed in two coats, with a 30-minute interval between the first and second coats.

[0014] As a further description of the above technical solution: In step S7, the initial maintenance involves closing the road to traffic for 2-4 hours to allow the sealant to completely cool and cure and the waterproofing agent to fully penetrate into the capillary pores of the concrete. Quality inspections include road surface smoothness, joint tightness, waterproofing agent film formation effect, and precast slab anchorage firmness. Traffic is opened after all indicators meet the standards. During the initial opening of traffic, heavy vehicles are restricted from passing, and the passage period is no less than 7 days.

[0015] The present invention has the following beneficial effects: This invention innovatively creates a four-level anti-settlement structural system consisting of point reinforcement of the roadbed, geogrid reinforcement, rubber mesh stress release, and precast slab bottom anchorage. Each structural layer performs its specific function and works synergistically to resist deformation: point reinforcement of the roadbed solves the load-bearing shortcomings of local soft foundations; geogrid reinforcement improves the overall crack resistance and settlement resistance of the roadbed, and evenly distributes the upper load to the roadbed; the rubber mesh utilizes the high elasticity and toughness of waste tires to effectively absorb and buffer the tensile stress generated by uneven settlement of the roadbed, avoiding stress concentration that could lead to pavement damage; the hemispherical protrusions arranged in a quincunx pattern at the bottom of the precast slab are embedded in the pores of the rubber mesh, forming a strong anchoring effect to prevent slab slippage and detachment, while the hyperboloid overlapping structure ensures tight splicing between precast slabs, further improving the overall stability of the pavement. This invention enhances the road's adaptability to uneven settlement, completely solving the persistent problems of slab breakage, cracking, and settlement in traditional rural roads from a structural design perspective, and extending the road's service life.

[0016] This invention abandons the existing technology's single-use approach of grinding waste tires into powder as an asphalt modifier, and realizes the high-value utilization of waste tires as structural layer materials: through sorting, cutting, silane coupling agent surface activation, prestressed weaving and other processes, waste tires are processed into flexible stress-relieving mesh sheets, which serve as the core skeleton of the road composite flexible stress-relieving layer, giving full play to the high elasticity, deformation resistance, and wear resistance of rubber materials; at the same time, the surface activation treatment, through the bridging effect of the coupling agent, greatly improves the interfacial adhesion between rubber and inorganic aggregates, forming a stable rubber skeleton and crushed stone filling composite structure, effectively solving the black pollution problem caused by waste tires, realizing the recycling of solid waste resources, and reducing the dependence of road construction on natural elastic materials, thus having significant ecological and environmental protection benefits and resource conservation benefits.

[0017] This invention constructs a triple waterproofing system consisting of an emulsified asphalt tack coat, a self-healing sealant, and a nano-silane hydrophobic layer. It achieves comprehensive, all-around waterproofing from three dimensions: the base layer, joints, and the entire slab. Each waterproofing layer works progressively and synergistically: the first layer, the emulsified asphalt tack coat, seals the surface pores of the composite flexible stress-relieving layer, preventing moisture from seeping into the base layer; the second layer, the modified rubber asphalt sealant, densely processes the joints of the precast slabs, its elastic deformation capacity adapting to minor road surface deformations and enabling self-repair of minor damage, completely blocking rainwater seepage from the joints; the third layer, the nano-silane waterproofing agent, seals the capillaries of the concrete slab at the molecular level, forming an overall hydrophobic layer, achieving full-section waterproofing of the road surface. This triple waterproofing system effectively blocks moisture seepage to the roadbed, preventing roadbed softening, frost heave, and subsidence, fundamentally solving the problem of water damage at joints in traditional rural roads, and further extending the service life of the roads.

[0018] The flexible stress-relieving mesh and precast concrete panels of this invention are both produced in a standardized manner in the factory. On-site work only requires the laying and assembly of each structural layer, eliminating the need for complex on-site formwork, mixing, and pouring procedures, thus greatly simplifying the construction process. At the same time, the base layer is constructed using a dry method, eliminating the need for cement mixing and generating no construction wastewater. The construction process is not affected by weather factors such as rainfall and low temperatures, enabling all-weather construction and significantly improving construction efficiency. This effectively reduces the impact of construction on agricultural production and transportation in rural areas and the daily travel of residents, making it particularly suitable for rural road construction with tight schedules and significant traffic disruptions. Attached Figure Description

[0019] Figure 1 This is a flowchart of the method of the present invention. Detailed Implementation

[0020] Reference Figure 1 The present invention provides a quick method for constructing hardened rural road surfaces, comprising the following steps: S1: Pre-treatment of waste tires and fabrication of grid cells: The core purpose of this step is to process waste tires into flexible stress-relieving mesh sheets that can serve as the framework for road structural layers. This addresses the issues of poor bonding between rubber and inorganic materials and the easy deformation of the mesh sheets under stress, thus realizing the material utilization of waste tires for structural layers. Specifically, it includes three sub-steps: 1.1 Waste Tire Sorting and Cutting: First, waste truck and lorry tires are collected and manually sorted to remove damaged tires with severely exposed bead wires, punctures, or cracks deeper than 2cm, ensuring the structural strength of the raw materials. CNC tire cutting equipment is then used to precisely cut qualified tires, cutting only the tire tread into rubber strips 3-8cm wide and 15-30cm long. Strips that are too narrow are prone to breakage during weaving and use, while strips that are too wide increase weaving difficulty and reduce the elasticity of the mesh. The length is designed to match the weaving size of the mesh, facilitating on-site splicing.

[0021] 1.2 Surface Activation Treatment of Rubber Strips: The cut rubber strips are completely immersed in a silane coupling agent solution for surface activation treatment. The immersion time is strictly controlled within 20-40 minutes. If the immersion is too short, the rubber surface will not be sufficiently activated, and the adhesion to inorganic materials will not be improved. If the immersion is too long, the construction cost will increase and there will be no additional effect. After immersion, the rubber strips are taken out and placed in a ventilated and cool place to air dry naturally for no less than 12 hours to ensure that the coupling agent forms a stable activated layer on the rubber surface. The core purpose of this process is to form chemical bonds between the rubber and subsequent aggregates and binders through the bridging effect of the coupling agent, which greatly improves the interfacial adhesion between the rubber surface and inorganic materials and avoids the phenomenon of rubber separating from aggregates during use.

[0022] 1.3 Mesh Weaving and Forming: High-strength polyester fiber rope is used as the weaving reinforcement. The activated and dried rubber strips are cross-woven, and a prestress of 0.5-1.0 MPa is applied to the rubber strips during the weaving process to keep them taut and prevent slack. This ensures the mesh remains stable under stress and during use, preventing deformation and loosening. Depending on the size of the construction site, the mesh is woven into standard sizes of 2m×3m or 1m×2m. The resulting flexible stress-relieving mesh has a mesh size of 8cm×8cm to 15cm×15cm, a thickness of 5-10cm, and a porosity of 30%-50%. This parameter design ensures that the mesh has sufficient elastic buffer space and provides ample porosity for aggregate filling, forming a composite structure foundation of rubber skeleton and crushed stone filling. After weaving, the mesh is visually inspected, and defective products with loose weaving or broken rubber strips are removed. The mesh is then stacked in a dry and ventilated place for later use.

[0023] S2: Subgrade treatment and leveling layer construction: The core purpose of this step is to comprehensively strengthen and level the original subgrade, improving its overall bearing capacity, deformation resistance, and impermeability. This provides a flat, stable, and solid working surface for the laying of all upper structural layers, fundamentally preventing pavement damage caused by uneven subgrade settlement. Specifically, it includes four sub-steps: 2.1 Subgrade Compaction: First, the road surface to be constructed is cleared, removing weeds, tree roots, humus, and other debris. After leveling the subgrade, an 18-20t roller is used for layered compaction, with each layer not exceeding 30cm in thickness. The compaction principle is to start with light compaction and gradually increase the intensity, starting slowly and gradually increasing the speed, and starting from the edges and then moving to the center. Each layer is compacted 6-8 times. After compaction, the subgrade compaction degree is tested using the ring cutter method to ensure that the compaction degree meets the design requirements for rural Class IV roads. For sections with localized weak foundations, excavation and replacement are used. After excavating 30-50cm of weak soil, well-graded crushed stone is replaced and compacted in layers to improve the bearing capacity of the local foundation and prevent localized settlement from affecting the overall stability of the road surface.

[0024] 2.2 Laying the geotextile isolation layer: A layer of 200-400g / ㎡ long-filament singed geotextile is fully laid on the compacted subgrade surface as a geotextile isolation layer. If the geotextile is too light, it will be easily damaged during construction and will not be able to play an isolation role; if it is too heavy, it will increase the construction cost. The geotextile is laid in a staggered manner, with an overlap width of not less than 20cm. The overlap is bonded with hot melt to ensure overall sealing. The core purpose of this process is to play a filtering and isolation role, preventing the subgrade soil from mixing with the upper aggregate under the action of water and vehicle loads, while preventing the upper aggregate from seeping into the subgrade, and ensuring the integrity of the subgrade and the upper structural layer.

[0025] 2.3 Laying the Reinforcing Layer: A layer of biaxially oriented plastic geogrid is fully laid on the surface of the geotextile as a reinforcing layer. The mesh size of the geogrid matches the size of the flexible stress-relieving mesh sheet prepared in step one, and its ultimate tensile strength is ≥50kN / m to ensure the reinforcement effect. The geogrid is also laid in a staggered manner, with an overlap width of not less than 15cm, and the overlap is fixed with cable ties. The core purpose of this process is to reinforce and strengthen the subgrade, disperse the stress generated by the upper load, improve the overall deformation resistance of the subgrade, and prevent local cracking and subsidence of the subgrade.

[0026] 2.4 Fine leveling layer construction: Lay a 3-5cm thick layer of clean stone chips on the surface of the geogrid. The mud content of the stone chips should be ≤1% to avoid excessive mud content affecting the permeability and flatness of the fine leveling layer. Use a screed and a level to perform fine leveling. Check the elevation multiple times during the leveling process to ensure that the flatness of the fine leveling layer surface is controlled within ±1cm. The core purpose of this process is to provide a flat and smooth working base for the subsequent laying of flexible stress-relieving mesh sheets, ensuring the flatness and integrity of the mesh sheet laying, and avoiding uneven stress in the mesh sheets due to uneven base surface.

[0027] S3: On-site installation of composite flexible stress relief layer: This step is the core structural layer construction process of this invention. Its core purpose is to construct a composite flexible stress-relieving layer with a rubber skeleton and crushed stone filling on the leveling layer, so as to absorb and buffer the stress of uneven settlement of the roadbed. At the same time, the first waterproof barrier is formed by spraying a tack coat to prevent water from seeping into the roadbed. Specifically, it includes four sub-steps: 3.1 Mesh Sheet Laying: The flexible stress-relieving mesh sheets prefabricated in step S1 are laid on the leveling layer in a staggered manner. The staggered laying can improve the overall stress dispersion ability of the mesh sheets. The overlap width between adjacent mesh sheets is not less than 10cm. The overlap is tied with high-strength plastic cable ties every 20cm to ensure that the ties are firm, so that all mesh sheets form an integral and continuous stress-relieving layer, avoiding displacement between mesh sheets and ensuring the integrity of stress buffering. During the laying process, avoid wrinkles and twists in the mesh sheets to ensure that they are flat and adhere to the leveling layer.

[0028] 3.2 First layer of aggregate filling: The first layer of aggregate is filled into the pores of the grid sheet. The aggregate is hard crushed stone with a particle size of 2-4cm and a mud content of ≤1% to ensure the strength and permeability of the aggregate. The filling thickness is strictly controlled to about 2 / 3 of the grid sheet thickness. After filling, a plate vibrator is used to compact the aggregate at a frequency of 20-30Hz to ensure that the crushed stone is fully embedded in the bottom of the grid and forms a tight bond with the rubber grid. The core purpose of this process is to provide a bottom rigid support for the rubber grid sheet, forming a basic structure of rubber soft skeleton and crushed stone hard filling, thereby improving the load-bearing capacity of the composite layer.

[0029] 3.3 Second Aggregate Filling: A second aggregate layer is filled on top of the first aggregate layer. The aggregate used is stone chips with a particle size of 0.5-1cm, and 10%-20% of Grade I fly ash is added to the stone chips. The addition of fly ash can improve the bonding force between aggregates and reduce material costs. The aggregate is filled to be flush with the surface of the grid sheet. After filling, a plate vibrator is used again to vibrate and compact it at a frequency of 25-35Hz for 30-60 seconds until the aggregate surface is flat, dense, and free of looseness. The core purpose of this process is to compact the pores of the grid sheet, fill the gaps in the first aggregate layer, and form a dense composite structure layer of rubber skeleton and crushed stone filling. This composite structure layer combines the elastic buffering performance of rubber with the rigid bearing performance of aggregate, effectively absorbing and buffering the tensile stress caused by uneven settlement of the roadbed.

[0030] 3.4 Prime Coat Spraying: Using an intelligent sprayer, slow-cracking emulsified asphalt prime coat is evenly sprayed onto the dense composite structural layer surface. The spraying dosage is strictly controlled at 0.8-1.2 kg / m² to ensure the prime coat evenly covers the composite layer surface and fully penetrates into the surface pores. After spraying, natural demulsification and curing should take at least 4 hours to allow the prime coat to form a continuous and dense waterproof film on the composite layer surface. The core purpose of this process is to seal the surface pores of the composite layer, forming the first waterproof barrier to prevent moisture from seeping into the interior of the composite layer and the subgrade, thus preventing subgrade softening.

[0031] S4: Factory production of precast concrete panels: The core purpose of this step is to factory-produce precast concrete panels with hemispherical anchoring protrusions and hyperboloid overlapping structures in a standardized manner. This ensures uniform panel quality, meets strength standards, and is dimensionally accurate, providing qualified pavement main components for rapid on-site assembly and paving. Simultaneously, a special structural design achieves anchoring and tight overlap between the panels and the composite flexible stress-relieving layer. This process includes five sub-steps: 4.1 Mold Preparation: High-precision steel molds are used as production molds for precast concrete panels. The flatness and dimensional error of the steel molds are controlled within ±0.5mm to ensure the accuracy of the precast panel dimensions. Several recesses are pre-set on the bottom of the steel mold to form hemispherical anchoring protrusions. The recesses are arranged in a quincunx pattern with a center-to-center spacing of 10-15cm. The diameter of the formed hemispherical protrusions is 3-5cm and the height is 2-3cm. The quincunx arrangement ensures uniform force distribution at the anchoring points and improves the anchoring effect between the precast panel and the composite layer. Wavy curved forming blocks are set on the sides of the steel mold to form a double-curved overlapping structure on the sides of the precast panel, which facilitates the tight splicing between precast panels and improves the sealing and stability of the joints. Before use, the molds are cleaned, polished, and oiled to prevent concrete from sticking to the molds.

[0032] 4.2 Reinforcing Mesh Installation: Precisely place a double-layer reinforcing mesh inside the cleaned steel mold. Use HRB400 grade round steel with a diameter of 6-8mm. The mesh size is 15cm x 15cm. Fix the upper and lower layers of mesh with positioning bars at 5-8cm intervals. Strictly control the concrete cover thickness to 2.5cm to prevent exposed rebar corrosion. After installation, check the position and firmness of the reinforcing mesh to ensure there is no misalignment or loosening. The core purpose of this process is to provide reinforcement for the precast concrete panel, improving its structural strength, crack resistance, and flexural strength to withstand the vehicle loads of rural roads.

[0033] 4.3 Concrete Pouring: Pour dry-hard concrete of strength grade C50 or above into the steel mold with the steel mesh installed. The slump of the concrete is controlled at 3-5cm. Dry-hard concrete effectively improves the density and strength of the precast slab and avoids defects such as honeycomb and pitting. During the pouring process, layered pouring is adopted, with each layer being 20-30cm thick. An immersion vibrator is used in conjunction with a plate vibrator for layered vibration. The vibrator moves from the edge of the mold to the center and vibrates until the concrete surface is smooth and free of air bubbles. This ensures that the concrete fully fills the raised pits at the bottom of the mold and the curved parts on the sides, ensuring the forming quality of the precast slab anchoring protrusions and the double-curved overlapping structure. After pouring, a power trowel is used to smooth the concrete surface to ensure that the panel surface is flat.

[0034] 4.4 Curing: After the concrete is smoothed, immediately cover its surface with a layer of geotextile and use steam curing. Steam curing is divided into three stages: heating, constant temperature, and cooling. The heating rate is ≤10℃ / h to prevent cracks from forming due to rapid temperature changes. The constant temperature stage is controlled at 50℃-60℃ for 8-12 hours to accelerate the early strength development of the concrete. The cooling rate is ≤15℃ / h, allowing it to cool naturally to room temperature. The core purpose of this process is to ensure that the concrete is fully hydrated and hardened, so that the precast slab reaches the design strength and avoids problems such as early cracking and insufficient strength.

[0035] 4.5 Demolding and Stacking: When the strength of the precast concrete panel reaches more than 75% of the design strength, a special demolding equipment is used for demolding. During the demolding process, the panels are lifted and placed gently to avoid collisions and scratches that could damage them. After demolding, the precast panels are inspected for appearance and dimensions, and unqualified products with surface damage, dimensional deviations, or poor anchoring protrusions are rejected. Qualified precast panels are stacked according to specifications, with wooden blocks used as spacers to prevent direct contact between panels. They are then placed in a dry and ventilated curing area to continue curing until they reach the design strength, ready for on-site construction.

[0036] S5: On-site assembly and installation of precast slabs: The core purpose of this step is to quickly and accurately assemble and lay precast concrete panels produced in the factory onto the composite flexible stress-relieving layer, achieving anchoring and interlocking between the precast panels and the underlying composite layer. This ensures the smoothness, integrity, and robustness of the main pavement structure, and significantly shortens construction time through on-site assembly. The process includes four sub-steps: 5.1 Laying and Setting Out: On the surface of the completed and cured composite flexible stress-relieving layer, a total station and a level are used for precise measurement and setting out. Then, the road edge line, the joint control line of the precast slab, and the elevation control line are marked with a chalk line. The elevation error is controlled within ±2mm, and the joint control line is clear and straight. After the setting out is completed, it is checked to ensure that the setting out is accurate and to provide a reliable positioning basis for the accurate laying of the precast slab.

[0037] 5.2 Precast Slab Laying: A small forklift is used to transport the precast concrete panels, cured to the design strength, to the laying location. Flexible lifting equipment is used during transportation to prevent damage to the edges and corners of the panels. During laying, the hemispherical protrusion at the bottom of the precast slab is placed downwards, and the panel is slowly lowered. The weight of the precast slab itself causes the hemispherical protrusion to embed into the surface pores of the composite flexible stress-relieving layer by 3-5mm, forming a multi-point interlocking anchoring structure. The core purpose of this process is to achieve a rigid connection between the precast slab and the lower composite flexible stress-relieving layer, preventing the slab from slipping or becoming detached under vehicle loads and roadbed settlement. At the same time, the elasticity of the composite layer allows the precast slab to adapt to minor roadbed settlements.

[0038] 5.3 Smoothness Adjustment: During the precast slab laying process, a 3m straightedge is used to check the road surface smoothness every 2m, with a check frequency of no less than 2 checks per panel. For any uneven areas detected, the precast slab is gently lifted and a small amount of clean stone chips are added underneath to level it, ensuring that the maximum road surface smoothness deviation is ≤3mm. The core purpose of this process is to ensure the overall smoothness of the road surface, improve the comfort of vehicle driving, and at the same time avoid stress concentration caused by local unevenness, which could lead to panel cracking.

[0039] 5.4 Joint Control: During the laying process, the joint width between adjacent precast slabs must be strictly controlled, precisely within 5-8mm. Excessively wide joints increase the amount of sealant needed and are prone to cracking, while excessively narrow joints can cause panel damage due to temperature deformation. Plastic wedges are used for temporary fixing at the joints, with a spacing of no more than 50cm between fixing points to ensure that all precast slab joints are uniform, consistent, and straight. The core purpose of this process is to reserve reasonable working space for subsequent joint treatment, ensure the sealing effect of the joints, and prevent displacement of the precast slabs during subsequent construction.

[0040] S6: Joint treatment and surface sealing: The core purpose of this step is to provide comprehensive sealing and crack-resistant treatment for the joints of the precast slabs, and to apply a waterproof coating to the entire road surface, constructing a multi-layered waterproof and crack-resistant system that seals the joints and provides overall waterproofing. This prevents water infiltration at the source, avoids water damage to the roadbed, and enhances the crack resistance and stability of the joints, extending the service life of the road surface. Specifically, it includes five sub-steps: 6.1 Joint Cleaning: High-pressure air of 0.5-0.8MPa is used to blow and clean the joints between precast slabs to remove dust, gravel, and debris. Then, the inner wall of the joint is repeatedly cleaned with a wire brush to ensure that there is no dust, debris, or water inside the joint, and that the inner wall of the joint is clean and dry. The core purpose of this process is to prevent impurities from affecting the bonding effect between the sealant and the concrete panel, and to ensure the firmness and tightness of the joint seal.

[0041] 6.2 Applying the interface agent: Apply the rubber asphalt interface agent evenly to the concrete panel surface on both sides of the joint. The application width should be strictly controlled to 3-5cm. Ensure that the application is even, without any omissions or accumulations. After the interface agent is applied, allow it to dry to the touch for about 30 minutes before proceeding with the subsequent sealant injection. The core purpose of this step is to enhance the adhesion between the sealant and the concrete panel, improve the sealing effect of the joint, and prevent the sealant from peeling off from the concrete.

[0042] 6.3 Sealant Injection: Modified rubber asphalt sealant is injected using a specialized joint injection gun. Before injection, the sealant is heated to 160℃-180℃ in a hot melt kettle to make it fluid. During heating, it is stirred continuously to ensure that the sealant is uniform and free of lumps. For the first injection, the sealant is slowly injected into the joint until it is 2-3mm below the surface of the slab. After the sealant has cooled and shrunk naturally for 30-60 minutes, a second injection is performed until the sealant is flush with the surface of the slab, without any depressions or protrusions. Modified rubber asphalt sealant has good elastic deformation capacity and self-healing properties, which can adapt to minor deformations of the road surface. Minor damage can be slightly expanded when exposed to heat or water to achieve self-repair. The core purpose of this process is to seal and waterproof the joint, preventing rainwater from seeping into the joint.

[0043] 6.4 Laying Anti-Crack Tape: After the joint has been poured and preliminarily cured, lay a 1.5-2.0mm thick layer of high-performance self-adhesive anti-crack tape across the joint surface. The width of the anti-crack tape should be controlled at 10-15cm to ensure complete coverage of the joint. When laying, gradually spread the anti-crack tape from the center to both sides to avoid hollow areas and curling edges. Then, use a rubber mallet to repeatedly press it from the center to both sides to ensure that the anti-crack tape adheres tightly to the panel surface. The core purpose of this process is to provide secondary protection for the joint, enhance its crack resistance and shear strength, and prevent cracking and edge peeling under vehicle loads.

[0044] 6.5 Surface Waterproofing Spraying: Using an agricultural sprayer, a nano-silane waterproofing agent is sprayed in a mist onto the entire road surface. The spraying dosage is strictly controlled at 0.2-0.3 kg / m². To ensure the spraying effect, a two-coat method is adopted. After the first spraying, wait 30 minutes to allow the waterproofing agent to initially penetrate before applying the second spraying to ensure that the waterproofing agent evenly covers the road surface. The nano-silane waterproofing agent can deeply penetrate into the capillaries of concrete, react chemically with the concrete, and form a dense hydrophobic layer, sealing the water seepage channels of the concrete at the molecular level. The core purpose of this process is to form a third waterproof barrier for the entire road surface, achieving full-section waterproofing and preventing water from seeping in through the capillaries of the concrete panel.

[0045] S7: Maintenance and Opening to Traffic: The core purpose of this step is to ensure that the joint sealant and road waterproofing agent function effectively. A comprehensive quality inspection ensures that all road surface indicators meet design and usage requirements. Simultaneously, initial traffic restrictions protect the road structure, ensuring the stability and lifespan of the road after it is put into normal use. This step includes three sub-steps: 7.1 Initial maintenance: After the road joint treatment and surface sealing are completed, the road should be closed to traffic immediately. The initial maintenance time is 2-4 hours. After the sealant has completely cooled and cured and the waterproofing agent has fully penetrated into the capillary pores of the concrete and formed a stable water-repellent layer, subsequent quality inspections can be carried out. During the maintenance period, personnel and vehicles are strictly prohibited from entering to avoid damaging the sealant and waterproofing agent film layer.

[0046] 7.2 Quality Inspection: Organize professional quality inspection personnel to conduct a comprehensive and detailed quality inspection of the completed road surface. The inspection contents mainly include: road surface flatness (tested with a 3m straightedge, maximum deviation ≤3mm), joint tightness (tested with water spray method, no water seepage), waterproofing agent film formation effect (uniform surface with no missed spraying), and precast slab anchorage firmness (no loosening or displacement). Any unqualified parts found in the inspection shall be rectified immediately until all indicators meet the standards.

[0047] 7.3 Opening to Traffic: Once all road surface quality indicators meet the standards, the road closure will be officially lifted and traffic will be opened. To protect the road surface structure, heavy vehicles (total mass > 10t) will be restricted from passing during the initial opening period, with the restriction period not less than 7 days, to prevent heavy vehicles from passing too early and causing the precast slabs to loosen or the joints to break. Later, weight limit signs can be set up according to the actual use of the road to adapt to the load requirements of rural roads.

[0048] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A quick method for constructing hardened rural road surfaces, characterized in that, Includes the following steps: S1: Pre-treatment of waste tires and manufacturing of grid units. The waste tires are sorted and cut, the rubber strips are surface activated, and the grid sheets are woven and formed in sequence to obtain flexible stress-relieving grid sheets with elastic buffering and structural stability. S2: Subgrade treatment and leveling layer construction, which involves mechanically compacting and locally improving the subgrade to be constructed, laying a geosynthetic isolation layer, laying a reinforcement layer, and constructing a fine leveling layer to form a flat, stable, and deformation-resistant subgrade working surface; S3: On-site paving of the composite flexible stress relief layer, which involves laying and fixing the flexible stress relief grid sheet, filling and compacting the first layer of aggregate, filling and compacting the second layer of aggregate, and spraying the tack coat oil to form a composite flexible stress relief layer with a rubber skeleton and crushed stone filling. S4: The factory production of precast concrete panels involves the sequential preparation of high-precision steel molds, installation of double-layer steel mesh, pouring and vibration of high-grade concrete, standardized curing, demolding and stacking of finished products, resulting in precast concrete panels with hemispherical anchoring protrusions and hyperboloid lap joint structures. S5: On-site assembly and laying of precast slabs, in sequence completing precise laying layout, anchored laying of precast slabs, dynamic adjustment of road surface flatness, and standardized control of slab joints, to complete the assembly of the main road structure; S6: Joint treatment and surface sealing, which involves joint cleaning, application of interface agent, layered injection of modified sealant, laying of crack-resistant tape across the joint, and overall waterproof spraying of the road surface to construct a multi-layer waterproof and crack-resistant system. S7: Maintenance and opening to traffic. The initial closure maintenance after construction and the quality inspection of various road surface indicators are completed in sequence. After passing the inspection, the road is officially opened to traffic.

2. The method for constructing a quick rural road hardening surface according to claim 1, characterized in that, In step S1, the waste tire sorting and cutting involves removing damaged tires with severely exposed bead wires, punctures in the tire body, or cracks deeper than 2cm. The qualified tire treads are cut into rubber strips with a width of 3-8cm and a length of 15-30cm using CNC tire cutting equipment. The surface activation treatment of the rubber strips involves immersing the rubber strips completely in a silane coupling agent solution for 20-40 minutes, then removing them and placing them in a ventilated and cool place to air dry naturally for no less than 12 hours.

3. The method for constructing a quick rural road hardening surface according to claim 1, characterized in that, In step S1, the mesh sheet is woven using high-strength polyester fiber rope as the braiding reinforcement. The activated rubber strips are cross-woven with warp and weft. During the weaving process, a prestress of 0.5-1.0 MPa is applied to the rubber strips to keep them taut. The resulting flexible stress-relieving mesh sheet has a mesh size of 8cm×8cm to 15cm×15cm, a thickness of 5-10cm, a porosity of 30%-50%, and a single mesh sheet specification of 2m×3m or 1m×2m, which is suitable for the on-site construction work surface.

4. The method for constructing a quick rural road hardening surface according to claim 1, characterized in that, In step S2, the roadbed compaction is carried out by 18-20t road roller in layers, with each layer not exceeding 30cm in thickness. In local soft foundation sections, 30-50cm of soft soil layer is excavated and replaced with crushed stone soil. The geotextile isolation layer is 200-400g / ㎡ long-filament singed geotextile with an overlap width of not less than 20cm, and the overlap is bonded by hot melt. The reinforcement layer is a biaxial tensile plastic geogrid that matches the size of the mesh sheet. The leveling layer is 3-5cm thick clean stone chips, which are leveled using a screed and a level, and the surface flatness is controlled within ±1cm.

5. The method for constructing a quick rural road hardening surface according to claim 1, characterized in that, In step S3, the flexible stress-relieving mesh is laid in a staggered manner, with an overlap width of no less than 10cm between adjacent meshes. The overlap is tied with high-strength plastic cable ties every 20cm. The first layer of aggregate consists of hard crushed stone with a particle size of 2-4cm, and the filling thickness is 2 / 3 of the thickness of the flexible stress-relieving mesh. It is compacted using a plate vibrator at a frequency of 20-30Hz. The second layer of aggregate consists of stone chips with a particle size of 0.5-1cm mixed with 10%-20% grade 1 fly ash, and is filled to be flush with the surface of the flexible stress-relieving mesh. It is compacted at a frequency of 25-35Hz for 30-60 seconds. The tack coat is a slow-cracking emulsified asphalt tack coat, with a spraying dosage of 0.8-1.2kg / ㎡. After spraying, it naturally demulsifies and cures for no less than 4 hours.

6. The method for constructing a quick rural road hardening surface according to claim 1, characterized in that, In step S4, the bottom of the high-precision steel mold is provided with a quincunx-shaped arrangement of pits, which are used to form hemispherical protrusions with a diameter of 3-5cm and a height of 2-3cm. The center-to-center spacing of the pits is 10-15cm. The sides of the steel mold are provided with wavy curved forming blocks to form a hyperboloid lap structure. The diameter of the steel bars in the double-layer steel mesh is 6-8mm, the mesh size is 15cm×15cm, the spacing between the upper and lower mesh layers is 5-8cm, and the thickness of the protective layer is controlled at 2.5cm. The concrete is dry-hard concrete with a strength grade of C50 or above, and the slump is controlled at 3-5cm. An immersion vibrator is used in conjunction with a plate vibrator for layered vibration until the concrete surface is covered with slurry and free of air bubbles.

7. The method for constructing a quick rural road hardening surface according to claim 1, characterized in that, In step S4, the curing method is steam curing, which is divided into three stages: heating, constant temperature, and cooling. The heating rate is ≤10℃ / h, the constant temperature stage temperature is 50℃-60℃, the curing time is 8-12 hours, and the cooling rate is ≤15℃ / h. When demolding, the concrete strength reaches more than 75% of the design strength, and after demolding, curing continues until the design strength is reached.

8. The method for constructing a quick rural road hardening surface according to claim 1, characterized in that, In step S5, the laying and setting out are carried out using a total station and a chalk line to mark the road edge line, slab joint control line, and elevation control line, with the elevation error controlled within ±2mm. The precast slabs are laid using a small forklift for lifting, relying on their own weight to make the hemispherical protrusions on the bottom of the slabs embed into the surface pores of the composite flexible stress release layer by 3-5mm to form multi-point anchorage. The flatness is checked every 2m with a 3m straightedge, and uneven areas are leveled with additional stone chips, with a maximum deviation ≤3mm. The joint width between adjacent precast slabs is controlled within 5-8mm, and temporary fixing is done with plastic wedges, with the fixing point spacing not exceeding 50cm.

9. A quick method for constructing hardened rural road surfaces according to claim 1, characterized in that, In step S6, the joint cleaning is performed by blowing with 0.5-0.8MPa high-pressure air and then cleaning with a wire brush to ensure that there is no floating dust, debris and water accumulation in the joint; the interface agent is a rubber asphalt interface agent, applied with a width of 3-5cm, applied evenly without omissions, and after surface drying, the sealant is injected; the sealant is a modified rubber asphalt sealant, heated to 160℃-180℃ to a fluid state, initially injected to a depth of 2-3mm below the board surface, cooled and shrunk for 30-60 minutes, and then injected a second time to be flush with the board surface; the crack-resistant tape is a 1.5-2.0mm thick high-performance self-adhesive crack-resistant tape, laid across the joint with a width of 10-15cm, and compacted from the center to both sides with a rubber mallet, without hollows or curling edges; the waterproof spray is a nano silane waterproof agent, applied by mist spraying, with a dosage of 0.2-0.3kg / ㎡, sprayed in two coats, with a 30-minute interval between the first and second coats.

10. A quick method for constructing hardened rural road surfaces according to claim 1, characterized in that, In step S7, the initial maintenance involves closing the road to traffic for 2-4 hours to allow the sealant to completely cool and cure and the waterproofing agent to fully penetrate into the capillary pores of the concrete. Quality inspections include road surface smoothness, joint tightness, waterproofing agent film formation effect, and precast slab anchorage firmness. Traffic is opened after all indicators meet the standards. During the initial opening of traffic, heavy vehicles are restricted from passing, and the passage period is no less than 7 days.

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