Prefabricated modular paving keel structure and road construction process

Abstract

The present application relates to the technical field of road paving, and particularly relates to a prefabricated modular paving keel structure and a road construction process, which comprises a lower bearing keel layer and an upper surface layer fixed keel layer, and a fixed contact surface is arranged at the overlapping part of the two; a flexible isolation cloth with water permeability, root resistance and high friction performance is first laid on the surface of a rammed roadbed and closely connected with the original soil; then granular filler is spread on the isolation cloth to compactly form a base stable layer; then a prefabricated double-layer keel module is embedded on the stable layer, granular filler is backfilled in the gap between the modules and the water permeable cavity of the keel, and the filler and the keel are interlocked to form a combined stress layer, and a porous drainage pipe connected with the water permeable system is arranged along the paving longitudinal slope; finally, a paving surface layer is fixed on the keel, and through the three-layer function progression and the interlocking combination of the filler and the keel, the integrated effects of high bearing, high water permeability, smooth drainage without water accumulation, winter frost heave resistance and ecological root resistance are realized.

Description

Technical Field

[0001] This invention relates to the field of road paving technology, and in particular to a prefabricated modular paving keel structure and road construction process. Background Technology

[0002] In outdoor paving scenarios such as municipal sidewalks, garden landscape walkways, waterfront boardwalks, and park plazas, wood-look paving structures have been widely used due to their combination of the natural beauty of solid wood and the durability of composite materials, gradually replacing traditional solid wood paving and hardened paving. With the continuous advancement of sponge city construction in China, outdoor paving projects have placed clear and stringent requirements on the permeability and settlement resistance of road structures. Simultaneously, the popularization of prefabricated construction technology is driving the paving industry towards prefabrication, modularization, efficient construction, and low maintenance throughout its entire lifecycle. There is a continuous technical demand within the industry for paving keel systems that combine high load-bearing capacity, high permeability, easy installation, and strong adaptability to various scenarios.

[0003] The existing keel system used in current wood-look paving techniques still has several technical shortcomings: Existing technologies focus primarily on optimizing the keel structure, with core innovations concentrated on keel member shapes and grid layouts. Conventional construction often employs on-site assembly of loose keels. Traditional stone and wood paving requires: demolition → removal → base layer reconstruction → paving → curing. Concrete strength must reach the required level within at least seven days. Combined with process coordination and weather constraints, the actual cycle often exceeds two weeks. This results in low construction efficiency and poor installation accuracy. Furthermore, existing paving techniques cannot balance load-bearing capacity and long-term permeability. Conventional methods either use hardened paving, which fails to meet the permeability requirements of sponge city construction, or simple permeable paving with insufficient load-bearing capacity, leading to bending deformation and uneven settlement over time. Additionally, rainwater infiltration can cause pore blockage, resulting in rapid degradation of permeability and preventing long-term stable permeability.

[0004] In existing paving processes, the keel and filler are installed separately, which cannot form a cohesive load-bearing system. This can easily lead to problems such as keel loosening and displacement, and filler loss. At the same time, the paving structure is highly solidified after it is formed, making it difficult to dismantle, modify, and maintain. The total cost of use over the entire life cycle is high, and it cannot meet the actual application needs such as scene updates and pipeline maintenance. Summary of the Invention

[0005] In view of the problems existing in the prior art, the present invention is proposed.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a prefabricated modular paving keel structure, comprising a lower load-bearing keel layer and an upper fixed keel layer, wherein the lower load-bearing keel layer and the upper fixed keel layer are stacked vertically, and the overlapping part is provided with a fixed overlapping contact surface; the top of the upper fixed keel layer is provided with a keel upper support surface for supporting the paving panel, and the lower load-bearing keel layer and the upper fixed keel layer enclose and form a permeable unit that runs vertically through the paving panel, and the whole is a double-layered stacked keel module unit.

[0007] As a preferred embodiment of the prefabricated modular paving keel structure of the present invention, the keel structure is a truss-type double-layer composite keel assembly, the lower load-bearing keel layer is a lower oblique truss keel layer, and the upper surface fixed keel layer is an upper transverse continuous keel layer. The lower oblique truss keel layer is formed by splicing multiple sets of intersecting oblique members to form a continuous truss load-bearing structure, and the upper transverse continuous keel layer is composed of multiple parallel continuous members. The two are fixed by overlapping and fixing the contact surfaces together.

[0008] As a preferred embodiment of the prefabricated modular paving keel structure of the present invention, wherein: the lower layer of the upper transverse continuous keel layer is a plurality of parallel lower longitudinal keels, and the upper layer of the upper transverse continuous keel layer is a plurality of parallel upper transverse keels. The lower longitudinal keel and the upper transverse keel are orthogonally overlapped, and the two enclose a grid rectangular permeable unit.

[0009] As a preferred embodiment of the prefabricated modular paving keel structure of the present invention, wherein: the lower layer of the lower oblique truss keel layer consists of multiple parallel lower oblique keels, and the upper layer of the lower oblique truss keel layer consists of multiple parallel upper oblique keels. The upper and lower inclined keels overlap at a predetermined angle, forming a grid-shaped permeable unit.

[0010] As a preferred embodiment of the prefabricated modular paving keel structure of the present invention, a limiting structure is provided at the overlapping and fixing contact surface.

[0011] As a preferred embodiment of the prefabricated modular paving keel structure of the present invention, wherein: the upper support surface of the keel is provided with positioning holes for fixing the paving panel; the bottom of the lower diagonal truss keel layer, the lower longitudinal keel, and the lower diagonal keel are all provided with reserved installation holes for anchoring with the paving pad layer.

[0012] As a preferred embodiment of the prefabricated modular paving keel structure of the present invention, wherein: both ends of the lower diagonal truss keel layer, the upper transverse continuous keel layer, the lower longitudinal keel, the upper transverse keel, the upper diagonal keel, and the lower diagonal keel are provided with limiting ends for splicing adjacent keel modules.

[0013] As a preferred embodiment of the prefabricated modular paving keel structure of the present invention, the lower load-bearing keel layer and the upper surface fixed keel layer are both integrally formed rods.

[0014] A road construction process, applied to any of the prefabricated modular paving keel structures described above, includes the following steps: S1. Subgrade pretreatment: The original subgrade soil of the paving site is compacted in layers to form a subgrade base course with a compaction degree ≥0.95. S2. Isolation and connection layer laying: The isolation layer is fully laid on the upper surface of the subgrade soil base, so that the isolation layer is completely bonded to the subgrade soil base; the isolation layer must meet the performance requirements of water permeability, root resistance, high friction and high load-bearing capacity; S3. Construction of the stable load-bearing system: On the upper surface of the isolation layer, a load-bearing sand and gravel cushion layer is laid and compacted in sequence, and a leveling sand and gravel cushion layer is laid to form a stable load-bearing foundation that enhances the overall stability of the structure; then, prefabricated double-layer composite keel is embedded in the leveling sand and gravel cushion layer according to the preset positioning, and sand and gravel filler is filled in the internal gap of the double-layer composite keel and between adjacent modules to form a water-permeable filling area of ​​the cushion layer, so that the filler and the double-layer composite keel together constitute a filler-keel combined load-bearing unit that works together to bear force and is permeable from top to bottom, meeting the preset stress strength and water permeability requirements. The top of the double-layer composite keel is provided with a keel upper support surface for supporting the surface layer; S4. Surface Paving: The surface layer is fixedly installed on the upper support surface of the keel. The surface layer meets the preset requirements for compressive strength, bending strength and bearing capacity, and the paving road construction is completed.

[0015] As a preferred embodiment of the road construction process described in this invention, in step S3, when prefabricating the double-layer composite keel, a panel fixing structure is simultaneously processed on the support surface of the keel, a pad anchoring hole is processed at the bottom of the double-layer composite keel, and splicing limiting ends are processed at both ends of the module. After the double-layer composite keel is spliced, the double-layer composite keel is anchored and fixed to the bearing sand and gravel cushion layer by passing anchors through the reserved installation holes at the bottom; the paving structure finally formed by the construction process achieves the technical effects of structural stability, ecological and environmental protection, and ease of construction and modification.

[0016] The beneficial effects of this invention are as follows: The upper and lower keel layers are fixed together by overlapping and bonding their contact surfaces, forming a synergistic load-bearing system. This allows the load transferred from the surface layer to be evenly distributed to the lower subbase, significantly improving the pavement structure's resistance to deformation and its adaptability to uneven settlement. The upper and lower keel layers enclose and form a permeable unit that runs vertically through the pavement, ensuring the permeability of the entire pavement cross-section and effectively preventing problems such as water accumulation on the road surface, softening of the base layer due to water immersion, and clogging of the subbase pores.

[0017] This process utilizes a three-layer progressive paving system consisting of a flexible functional fabric, a granular stabilizing layer, and a keel filler layer to form a synergistic load-bearing structure. The first layer, the flexible isolation fabric, is tightly bonded to the original subgrade soil, effectively constraining the slippage of the subbase due to its high frictional properties, while uniformly distributing the upper load to the subgrade. The second stabilizing layer and the third combined load-bearing layer utilize the interlocking and mutual squeezing effect of the granular filler and the keel mesh to transform the concentrated load transmitted from the surface layer into a dispersed stress transmission between the granules, greatly improving the structural integrity and resistance to uneven settlement of the paving system.

[0018] The first layer of flexible fabric has the dual functions of high permeability and long-term root barrier. While ensuring rapid infiltration of rainwater, it can effectively prevent plant roots from penetrating and damaging the roadbed, and prevent frost heave and mudslides. The second and third layers are filled with granular filler to construct a vertically continuous permeable channel network. Together with the porous drainage pipes connected to the permeable system, a dual drainage system of vertical infiltration and horizontal drainage is formed. This ensures that the overall permeability coefficient of the paving system meets the standards for sponge city construction, and can quickly drain stagnant water, ensuring smooth drainage throughout the process. It fundamentally solves the problem of structural damage caused by frost heave due to low temperature water accumulation in winter, and greatly improves the all-weather adaptability and service life of the paving structure. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the overall structure of the paving keel structure of the present invention; Figure 2 This is a schematic diagram of the upper transverse continuous keel layer in this invention; Figure 3 This is a schematic diagram of the lower-level oblique truss keel layer in this invention; Figure 4 This is a schematic cross-sectional view of the road surface structure in this invention.

[0021] Figure reference numerals: 100, Truss-type double-layer composite keel assembly; 101, Lower layer diagonal truss keel layer; 102, Upper layer transverse continuous keel layer; 103, Composite fixed contact surface; 104, Lower layer longitudinal keel; 105, Upper layer transverse keel; 106, Grid rectangular permeable unit; 107, Upper layer diagonal keel; 108, Lower layer diagonal keel; 109, Grid diamond permeable unit; 201. Subgrade soil base; 202. Isolation layer; 203. Bearing sand and gravel cushion layer; 204. Leveling sand and gravel cushion layer; 205. Double-layer composite joists; 206. Joist upper support surface; 207. Permeable filling area of ​​cushion layer; 208. Surface layer slab. Detailed Implementation

[0022] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0023] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0024] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments. Example

[0025] Reference Figures 1-4 This is the first embodiment of the present invention, which provides a prefabricated modular paving keel structure.

[0026] Specifically, it includes a lower load-bearing keel layer and an upper fixed keel layer. The lower load-bearing keel layer and the upper fixed keel layer are stacked on top of each other, and the overlapping part is provided with a fixed overlapping contact surface 103. The top of the upper fixed keel layer is provided with a keel upper support surface 206 for supporting the paving panel. The lower load-bearing keel layer and the upper fixed keel layer enclose each other to form a permeable unit that runs vertically through the floor. The whole is a double-layered stacked keel 205 module unit.

[0027] In this embodiment, the core of the prefabricated modular paving keel structure is a double-layered composite keel module unit 205. The entire module is manufactured using standardized prefabrication in a factory and can be modularly adjusted according to the actual dimensions of the paving site. The core module includes a lower load-bearing keel layer and an upper fixed keel layer, both layers of keels are made of integrally molded rods, suitable for the conventional load-bearing requirements of landscape paving and municipal sidewalks. The upper surface of the lower load-bearing keel layer is completely fitted with the lower surface of the upper fixed keel layer, forming a composite fixed contact surface 103. The contact surface is seamless, ensuring complete load transfer between the upper and lower keels and preventing deformation of the rods due to localized stress concentration. The top of the upper fixed keel layer is a flat keel support surface 206. The flat surface of the support surface is used to directly adhere and fix the paving panel, preventing warping and abnormal noise after the panel is laid. The gaps between the members of the lower load-bearing keel layer and the gaps between the members of the upper fixed keel layer are aligned vertically to form a permeable unit that runs vertically through the surface, ensuring that rainwater can seep vertically into the road surface without obstruction or clogging.

[0028] Preferably, the keel structure is a truss-type double-layer composite keel assembly 100, the lower load-bearing keel layer is a lower diagonal truss keel layer 101, and the upper fixed keel layer is an upper transverse continuous keel layer 102. The lower skew truss keel layer 101 is formed by splicing multiple sets of intersecting skew members to form a continuous truss load-bearing structure, and the upper transverse continuous keel layer 102 is composed of multiple parallel continuous members. The two are fixed together by overlapping and fixing the contact surface 103.

[0029] The keel structure is specifically a truss-type double-layer composite keel assembly 100, where the lower load-bearing keel layer is the lower diagonal truss keel layer 101, and the upper fixed keel layer is the upper transverse continuous keel layer 102. The lower diagonal truss keel layer 101 is spliced ​​together from multiple sets of diagonally intersecting members with a cross angle of 45°, forming a continuous triangular truss load-bearing structure that can adapt to large-span, high-load-bearing paving scenarios.

[0030] The upper transverse continuous keel layer 102 is composed of multiple parallel continuous members with a center-to-center distance of 500mm between adjacent continuous members. It corresponds one-to-one with the triangular nodes of the lower oblique truss keel layer 101. The contact surfaces of the two form a complete overlapping and fixed contact surface 103, which ensures that the upper load can be completely transferred to the lower truss structure through the nodes and then evenly distributed to the lower pad layer.

[0031] The lower layer of the upper transverse continuous keel layer 102 consists of multiple parallel lower longitudinal keels 104, and the upper layer of the upper transverse continuous keel layer 102 consists of multiple parallel upper transverse keels 105. The lower longitudinal keel 104 and the upper transverse keel 105 are orthogonally overlapped at 90°, and the two enclose each other to form a grid rectangular permeable unit 106.

[0032] The upper transverse continuous keel layer 102 is a double-layer orthogonal grid structure. The lower layer consists of multiple parallel lower longitudinal keels 104, and the upper layer consists of multiple parallel upper transverse keels 105. Both layers use structural members and are orthogonally overlapped at 90°, with spot welding used at the intersections to form a stable rectangular grid frame. The lower longitudinal keels 104 and the upper transverse keels 105 enclose a grid-rectangular permeable unit 106. The permeable area of ​​each unit is uniform and can be perfectly aligned with the joints of the paved panels, further improving rainwater infiltration efficiency.

[0033] The orthogonal grid structure distributes surface loads more evenly, and all four corners of a single panel can be mapped to grid nodes, avoiding cracking and deformation caused by single-point stress on the panel. At the same time, no complicated angle calibration is required during construction layout; positioning can be done simply by following the longitudinal and transverse lines, greatly reducing the difficulty of on-site operations.

[0034] Preferably, the lower layer of the lower skew truss keel layer 101 consists of multiple parallel lower skew keels 108, and the upper layer of the lower skew truss keel layer 101 consists of multiple parallel upper skew keels 107. The upper diagonal keel 107 and the lower diagonal keel 108 overlap at a predetermined angle, and the two enclose each other to form a grid-shaped permeable unit 109.

[0035] Among them, the lower skew truss keel layer 101 is optimized with skew grid. The lower skew truss keel layer 101 is a double-layer skew grid structure. Its lower layer consists of multiple parallel lower skew keels 108, and its upper layer consists of multiple parallel upper skew keels 107. Both layers of members are members, and the two are superimposed at a preset angle of 45°. The intersection is fixed by spot welding to form a continuous diamond grid structure.

[0036] For non-standard scenarios such as curved paving and irregular corner paving, the preset angle can be flexibly adjusted to adaptable angles such as 30° and 60° to perfectly fit the contour requirements of irregular paving without the need for on-site cutting of poles. The upper diagonal keel 107 and the lower diagonal keel 108 enclose a grid diamond-shaped permeable unit 109, with continuous permeable channels, ensuring consistent permeability across the entire cross-section even in irregular paving scenarios, with no permeable blind spots. Example

[0037] Reference Figures 1-4 This is the second embodiment of the present invention, which is implemented based on the previous embodiment.

[0038] Specifically, a limiting structure is provided at the overlapping and fixed contact surface 103.

[0039] A limiting structure is provided at the overlapping and fixed contact surface 103. When the upper and lower keels are overlapped, the horizontal limiting is achieved first, and then the vertical fixing is completed by bolts. This can completely avoid the problem of horizontal slippage and misalignment of the upper and lower keels during use. Especially in irregular paving and road sections with side slopes, the limiting structure can greatly improve the stability of the overall structure and prevent the structure from loosening under long-term load.

[0040] The upper support surface 206 of the keel is provided with positioning holes for fixing the paving panel; the bottom of the lower diagonal truss keel layer 101, the lower longitudinal keel 104, and the lower diagonal keel 108 are all provided with reserved installation holes for anchoring with the paving pad layer.

[0041] The keel upper support surface 206 is provided with positioning holes for fixing the paving panel. The positioning holes are prefabricated round holes with a diameter of 5mm. A set of them is set every 300mm along the length of the keel, corresponding one-to-one with the fixing point of the paving panel. The panel can be directly aligned and fixed during installation without secondary adjustment.

[0042] The bottom of the lower diagonal truss keel layer 101, the lower longitudinal keel 104, and the lower diagonal keel 108 are all provided with reserved installation holes for anchoring with the pavement subbase. The reserved installation holes are 12mm diameter through holes, which are compatible with M10 expansion bolts. A set of holes is set every 1000mm along the length of the keel. The holes are opened simultaneously during factory prefabrication. On-site anchoring can be completed simply by inserting expansion bolts, which greatly improves installation efficiency.

[0043] The lower diagonal truss keel layer 101, the upper transverse continuous keel layer 102, the lower longitudinal keel 104, the upper transverse keel 105, the upper diagonal keel 107, and the lower diagonal keel 108 are all provided with limiting ends for splicing adjacent keel modules.

[0044] The lower oblique truss keel layer 101, the upper transverse continuous keel layer 102, the lower longitudinal keel 104, the upper transverse keel 105, the upper oblique keel 107, and the lower oblique keel 108 are all provided with limiting ends for splicing adjacent keel modules.

[0045] When two adjacent keel modules are spliced, the positioning and straightness control of the modules can be quickly achieved through the matching installation of the limiting end, without the need for repeated on-site line adjustments. At the same time, it can ensure that the keel members of adjacent modules are completely aligned, the permeable units are connected without misalignment, and avoid problems such as water accumulation and panel warping at the splicing point.

[0046] Both the lower load-bearing keel layer and the upper fixed keel layer are integrally molded rods.

[0047] Both the lower load-bearing keel layer and the upper fixed keel layer are integrally molded rods. The materials are mainly calcium carbonate and high molecular resin, with added anti-aging agents and toughening agents, and are extruded in one piece. Compared with traditional solid wood and ordinary wood-plastic materials, the anti-corrosion level reaches the highest level, with no risk of insect infestation or rot. The outdoor service life can reach more than 20 years. At the same time, it has excellent resistance to ultraviolet fading and no obvious discoloration or cracking after long-term outdoor use, making it fully suitable for the harsh outdoor paving environment. Example

[0048] This is the third embodiment of the present invention, which provides a road construction process.

[0049] Specifically, it includes the following steps: S1. Subgrade pretreatment: The original subgrade soil of the paving site is compacted in layers to form a subgrade base course with a compaction degree ≥0.95 201. The paving site is cleared, removing debris, loose soil, and weak soil layers. The original soil or backfill is then backfilled and compacted in layers, with each layer not exceeding 300mm in thickness. A road roller is used for compaction, ultimately forming a subgrade soil base 201 with a compaction degree ≥0.95. The surface flatness error of the formed subgrade soil base 201 is not greater than 10mm, and the elevation error is not greater than ±20mm, providing a flat and stable subgrade foundation for the subsequent paving system and ensuring a stable connection between the superstructure and the original subgrade.

[0050] By adopting a layered backfilling and compaction process, the problem of uneven settlement of the roadbed can be avoided at the source. At the same time, the overall compaction degree of the roadbed is uniform and controllable, providing a uniform stress foundation for subsequent paving, avoiding cracking and water accumulation in the upper paving structure caused by local settlement of the roadbed, and further improving the long-term stability of the paving structure.

[0051] S2. Isolation and connection layer laying: 80g / m² high permeability non-woven fabric is fully laid on the upper surface of the subgrade soil base 201 as isolation layer 202, so that the isolation layer 202 is completely bonded to the subgrade soil base 201; the isolation layer 202 must meet the performance requirements of water permeability, root resistance, high friction and high load-bearing capacity. This step is the first core innovation layer of this process. The isolation and connection layer is fully laid on the upper surface of the subgrade soil base 201. There is no unique limitation on the material or type of this layer. It is only clear that its core performance must meet the requirements of water permeability, root resistance, high friction and high load-bearing capacity. Any material that meets the above performance requirements, such as high water permeability non-woven fabric or high load-bearing permeable fabric, can be used to form the isolation layer 202.

[0052] During installation, the isolation layer 202 should be fully bonded and directly connected to the subgrade soil base 201, with an overlap width of no less than 100mm between adjacent strips. The isolation layer should be kept flat, without wrinkles or damage throughout the process to form a complete reverse filter isolation system.

[0053] This layer, through its core performance limitations, ensures that rainwater can smoothly infiltrate downwards while effectively preventing plant roots from piercing and damaging the pavement structure and preventing the subgrade soil from being washed away by rainwater and causing blockage of the subgrade pores. At the same time, its high friction performance enables a seamless and stable connection between the subgrade and the superstructure, avoiding slippage and misalignment of the supergrade subgrade. This is the fundamental guarantee for the stable permeable ecological technology of this process.

[0054] In addition, this layer adopts a flexible fabric paving process, which can adapt to paving scenarios with different geological conditions and climates, and can also block the rise of capillary water in the subgrade. Combined with subsequent drainage, it can further avoid the problem of frost heave caused by water freezing in the subgrade at low winter temperatures, and greatly improve the all-weather adaptability of the paving structure. At the same time, the complete reverse filtration and isolation system can ensure the long-term stability of the subbase gradation, avoid the blockage of permeable pores, and achieve long-term stable compliance with permeability standards.

[0055] S3. Construction of the stable bearing system: A 150mm thick natural sand and gravel cushion layer (203) and a 50mm thick natural sand and gravel cushion layer (204) are sequentially laid and compacted on the upper surface of the isolation layer (202) to form a stable bearing foundation; the gradation of the natural sand and gravel cushion layers is 25% Ø10-20mm gravel and 25%... Ø30-40mm gravel and 50% coarse yellow sand are compacted and leveled; then, prefabricated double-layer composite keel 205 is embedded in the leveled sand and gravel pad 204 according to the preset positioning. In the double-layer composite keel (205), the lower diagonal truss keel layer 101 adopts a wood-colored mineral steel-plastic rod with a cross section of 140×25mm and a length of 4000mm; the upper transverse continuous keel layer 102 adopts mineral steel-plastic with a cross section of 50×32mm (arranged in a 500mm continuous length) and mineral steel-plastic with a cross section of 50×50mm (arranged in an 800mm continuous length), and is connected by expansion nails. Simultaneously, sand and gravel filler is filled into the internal gaps of the double-layer composite keel 205 and between adjacent modules to form a permeable filling area 207 of the cushion layer. This allows the filler and the double-layer composite keel 205 to jointly form a filler-keel combination bearing unit that is synergistically stressed and permeable from top to bottom, meeting the preset stress strength and permeability requirements. The top of the double-layer composite keel 205 is provided with a keel upper support surface 206 for supporting the surface layer. This step is the second core innovation layer of this process, the core of which is to construct a synergistic force-bearing system of a stabilizing layer + filler-keel combined load-bearing unit.

[0056] On the upper surface of the isolation layer 202, a load-bearing sand and gravel cushion layer 203 is laid and compacted in sequence, followed by a leveling sand and gravel cushion layer 204. These two layers together constitute the stabilizing layer of this process, used to enhance the overall stability and load distribution uniformity of the pavement structure. Any aggregate that meets the gradation requirements, such as crushed stone or fine sand, can be used; there are no material limitations on the aggregate. After laying, the overall elevation error is controlled to be no more than 5mm, and the compaction degree meets the preset load-bearing requirements, providing a uniform and stable load-bearing foundation for the superstructure.

[0057] The process of laying a load-bearing sub-layer and a leveling sub-layer in layers not only achieves a wide and uniform distribution of load through the lower load-bearing sub-layer, greatly improving the overall load-bearing capacity of the paving system, but also achieves high-precision flatness control through the upper leveling sub-layer. This eliminates the need for secondary leveling and cutting on-site, significantly reducing the difficulty of assembling the subsequent keel modules and improving on-site construction efficiency. At the same time, the layered and graded design further enhances the continuity of permeable channels, avoids clogging of pores in a single sub-layer, and forms a complete permeable system with the isolation layer and combined load-bearing units.

[0058] Within the leveled gravel cushion layer 204, lines are marked according to the design spacing to indicate the installation edge lines and anchor points of each prefabricated module, with a line position error of no more than 2mm. Simultaneously, filler material is laid and embedded with the factory-prefabricated double-layer composite keel 205, ensuring the filler material completely fills the internal gaps of the double-layer composite keel 205 and between adjacent modules, forming a permeable filling area 207 in the cushion layer. The filler material and the double-layer composite keel 205 together constitute an inseparable, collaboratively stressed filler-keel combined load-bearing unit. Both are constructed synchronously and formed collaboratively, jointly achieving the core functions of stable stress and vertical permeability, meeting the preset stress strength and permeability requirements. This is the core carrier of the stable permeable ecological technology of this process.

[0059] By forming a complete interlocking and inter-extrusion effect between the filler and the keel mesh, the concentrated load transmitted from the surface layer is evenly distributed to the underlying subbase, avoiding the industry pain points of loosening of the keel, loss of filler, and uneven stress caused by the separate construction of the keel and filler in the existing technology. At the same time, the continuous and permeable water channel formed by the two can ensure that rainwater infiltrates quickly without stagnation, and can be quickly drained with the help of porous drainage pipes, further enhancing the anti-frost heave effect. In addition, the modular installation process does not require on-site pouring and wet work, and individual modules can be independently disassembled and modified in the later stage without damaging the surrounding paving structure, which greatly reduces the maintenance cost throughout the entire life cycle.

[0060] During the embedding process of the modules, the splicing and positioning of adjacent double-layer laminated keels 205 are completed through the limiting ends at both ends of the modules, and the flatness and straightness of the modules are adjusted, so that the upper supporting surface 206 of the keel at the top of the double-layer laminated keel 205 is flush with the upper surface of the leveling sand-gravel cushion layer 204; after the splicing is completed, an anchor member is passed through the pre-reserved mounting hole at the bottom of the double-layer laminated keel 205 to anchor and fix it to the load-bearing sand-gravel cushion layer 203, the spacing between adjacent anchoring points is ≤1000mm, ensuring that each module has at least 2 sets of anchoring points, so as to prevent the modules from floating or displacing during use.

[0061] After the modules are spliced and anchored, porous drainage pipes are laid at the splicing positions of adjacent double-layer laminated keel 205 modules along the longitudinal slope direction of the paved road. There is no limitation on the material of the pipe, and it is only required to meet the core performance requirements of pressure resistance, corrosion resistance, water permeability and drainage; during laying, the pipe body is fully communicated with the permeable filling zone 207 of the cushion layer and the through permeable units of the keel modules, forming a dual drainage system of vertical infiltration and horizontal drainage. Rainwater that infiltrates from the surface layer and is retained in the cushion layer can be quickly drained, ensuring smooth drainage without water accumulation throughout the whole process, fundamentally avoiding the problems of pavement structure heaving, cracking and keel loosening caused by freezing and expansion of water accumulated in the pores of the cushion layer in low-temperature winter environments, greatly improving the frost heave resistance performance and all-climate environment adaptability of the pavement structure, and effectively extending the service life of the pavement structure.

[0062] Through the synergistic effect of the filler and the keel, the pain points in the prior art caused by separate construction of the keel and the filler, such as uneven stress, easy loosening and displacement, filler loss and permeability performance attenuation, are solved. Meanwhile, all prefabricated components are subjected to standardized processing in the factory, no secondary cutting or hole opening is required on site, which greatly improves the construction efficiency. In addition, the modules can be directly disassembled in the later stage to realize rapid demolition and modification of the pavement structure without damaging the roadbed and cushion layer system.

[0063] S4, Surface layer paving: The surface layer plate 208 is fixedly installed above the upper supporting surface 206 of the keel. The surface layer plate 208 meets the preset performance requirements of pressure resistance, bending resistance and bearing capacity, thus completing the construction of the paved road.

[0064] In this step, the keel structure, as a supporting prefabricated component of the combined load-bearing unit, cooperates with the filler to solve the pain points in the prior art caused by separate construction of the keel and the filler, such as uneven stress, easy loosening and displacement, filler loss and permeability performance attenuation. Meanwhile, all prefabricated components are subjected to standardized processing in the factory, no secondary cutting or hole opening is required on site, which greatly improves the construction efficiency. In addition, the modules can be directly disassembled in the later stage to realize rapid demolition and modification of the pavement structure without damaging the roadbed and cushion layer system.

[0065] In this step, the surface material is required to meet the preset requirements for compressive strength, bending strength, and load-bearing capacity. No unique or mandatory restrictions are placed on the material or type. Any paving material that meets the above performance requirements, such as surface board 208, composite board, or natural stone, can be used.

[0066] During construction, the selected surface material is fixed to the upper support surface 206 of the keel using fasteners. After the surface layer is paved, its joints correspond vertically with the drainage channels of the permeable units and porous drainage pipes below, ensuring that water collected in the surface layer can quickly enter the drainage system through the joints. This prevents water accumulation on the surface layer and freezing in the joints, further improving the anti-freezing effect in winter and the safety of pedestrians. Expansion joints are reserved between adjacent surface materials to accommodate the thermal expansion and contraction of the materials, preventing warping and cracking of the surface layer under high and low temperature cycles, improving the appearance integrity and long-term service life of the paving structure, and finally completing the construction of the entire paved road.

[0067] Preferably, in step S3, when prefabricating the double-layer composite keel 205, the panel fixing structure is processed on the support surface 206 of the keel, the pad anchoring installation hole is processed at the bottom of the double-layer composite keel 205, and the splicing limiting end is processed at both ends of the module. After the double-layer composite keel 205 is spliced, the double-layer composite keel 205 is anchored to the bearing sand and gravel cushion layer 203 through the anchors passing through the reserved installation holes at the bottom. The spacing between adjacent anchor points is ≤1000mm. The paving structure finally formed by the construction process achieves the technical effects of structural stability, ecological and environmental protection, and ease of construction and modification.

[0068] In step S3, after the double-layer composite keel 205 module is spliced, the double-layer composite keel 205 module is anchored to the bearing sand and gravel pad layer 203 by passing M10 expansion nails through the reserved installation holes of the lower bearing keel layer. The spacing between adjacent anchor points is ≤1000mm to ensure that each module has at least 2 sets of anchor points to prevent the module from floating or shifting during use.

[0069] This paving construction method uses factory-prefabricated modules with detachable mechanical connections, which enables rapid assembly of components and secure structural locking. While ensuring construction safety and project quality, it also facilitates the replacement and maintenance of components later. The resulting paving structure can simultaneously achieve multiple comprehensive advantages, such as structural stability and reliability, long-term stable permeability, green and environmentally friendly features, simple on-site construction, and easy dismantling and maintenance later.

[0070] Construction does not require large quantities of main materials such as concrete and asphalt, eliminating long-distance transportation of raw materials and on-site mixing and processing, thus reducing multiple additional costs from the source. Only two construction workers are needed to work together, and the project can be completed and opened to traffic on the same day, shortening the overall construction period by more than 66% compared to traditional methods. The entire process does not require the entry of large construction equipment or rely on experienced professional technicians; ordinary workers can independently carry out construction work after a brief pre-job training. All components adopt a modular prefabrication model in the factory, with readily available stock for immediate supply and on-site assembly and use. The project progresses daily from start to finish, abandoning the construction pace of traditional projects that often takes several weeks. It breaks the limitation of traditional concrete paving requiring a 7-day curing period, allowing the paving to bear load immediately after assembly, with the overall construction cycle only one-third of that of traditional methods. There is no dust generation on the construction site, and the operation noise is controllable, ensuring a clean and pollution-free construction process that meets the requirements of green construction.

[0071] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A prefabricated modular paving keel structure, comprising a lower load-bearing keel layer and an upper surface fixing keel layer, characterized in that: The lower load-bearing keel layer and the upper surface fixed keel layer are stacked on top of each other, and the overlapping part is provided with a fixed overlapping contact surface (103); the top of the upper surface fixed keel layer is provided with a keel upper support surface (206) for supporting the paving panel. The lower load-bearing keel layer and the upper surface fixed keel layer enclose each other to form a permeable unit that runs through the upper and lower parts. The whole is a double-layer stacked keel (205) module unit.

2. The prefabricated modular paving keel structure as described in claim 1, characterized in that: The keel structure is a truss-type double-layer composite keel assembly (100), the lower load-bearing keel layer is a lower diagonal truss keel layer (101), and the upper layer fixed keel layer is an upper transverse continuous keel layer (102). The lower oblique truss keel layer (101) is formed by splicing multiple sets of intersecting oblique members to form a continuous truss force-bearing structure, and the upper transverse continuous keel layer (102) is composed of multiple parallel continuous members. The two are fixed together by overlapping and fixing the contact surface (103).

3. The prefabricated modular paving keel structure as described in claim 2, characterized in that: The lower layer of the upper transverse continuous keel layer (102) consists of multiple parallel lower longitudinal keels (104), and the upper layer of the upper transverse continuous keel layer (102) consists of multiple parallel upper transverse keels (105). The lower longitudinal keel (104) and the upper transverse keel (105) are orthogonally overlapped at 90°, and the two enclose a grid rectangular permeable unit (106).

4. The prefabricated modular paving keel structure as described in claim 3, characterized in that: The lower layer of the lower oblique truss keel layer (101) consists of multiple parallel lower oblique keels (108), and the upper layer of the lower oblique truss keel layer (101) consists of multiple parallel upper oblique keels (107). The upper oblique keel (107) and the lower oblique keel (108) are overlapped at a preset angle, and the two enclose each other to form a grid diamond permeable unit (109).

5. The prefabricated modular paving keel structure as described in claim 1, characterized in that: A limiting structure is provided at the overlapping fixed contact surface (103).

6. The prefabricated modular paving keel structure as described in claim 2 or 4, characterized in that: The upper support surface (206) of the keel is provided with positioning holes for fixing the paving panel; the bottom of the lower diagonal truss keel layer (101), the lower longitudinal keel (104), and the lower diagonal keel (108) are all provided with reserved installation holes for anchoring with the paving pad layer.

7. The prefabricated modular paving keel structure as described in claim 2 or 4, characterized in that: The lower oblique truss keel layer (101), the upper transverse continuous keel layer (102), the lower longitudinal keel (104), the upper transverse keel (105), the upper oblique keel (107), and the lower oblique keel (108) are all provided with limiting ends for splicing adjacent keel modules.

8. The prefabricated modular paving keel structure as described in claim 1, characterized in that: Both the lower load-bearing keel layer and the upper fixed keel layer are integrally formed rods.

9. A road construction process, employing the prefabricated modular paving keel structure as described in any one of claims 1 to 8, characterized in that: Includes the following steps S1. Subgrade pretreatment: The original subgrade soil of the paving site is compacted in layers to form a subgrade soil base with a compaction degree ≥0.95 (201). S2. Laying of isolation and connection layer: The isolation layer (202) is fully laid on the upper surface of the subgrade soil base (201) so that the isolation layer (202) and the subgrade soil base (201) are completely bonded and connected; the isolation layer (202) must meet the performance requirements of water permeability, root resistance, high friction and high load bearing. S3. Construction of stable bearing system: On the upper surface of the isolation layer (202), a bearing sand and gravel cushion layer (203) is laid and rolled, and a leveling sand and gravel cushion layer (204) is laid to form a stable bearing foundation that enhances the overall stability of the structure; then, a prefabricated double-layer composite keel (205) is embedded in the leveling sand and gravel cushion layer (204) according to the preset positioning, and sand and gravel filler is filled in the internal gap of the double-layer composite keel (205) and between adjacent modules to form a permeable filling area (207) of the cushion layer, so that the filler and the double-layer composite keel (205) together constitute a filler-keel combined bearing unit that is synergistically stressed and permeable from top to bottom, meeting the preset stress strength and permeability requirements. The top of the double-layer composite keel (205) is provided with a keel upper support surface (206) for supporting the surface layer. S4. Surface Paving: The surface plate (208) is fixedly installed on the upper support surface (206) of the keel. The surface plate (208) meets the preset requirements for compressive strength, bending strength and bearing capacity, and the paving road construction is completed.

10. The road construction process as described in claim 9, characterized in that: In step S3, when prefabricating the double-layer composite keel (205), the panel fixing structure is processed on the support surface (206) of the keel, the pad anchoring installation hole is processed at the bottom of the double-layer composite keel (205), and the splicing limiting end is processed at both ends of the module. After the double-layer composite keel (205) is spliced, the double-layer composite keel (205) is anchored to the bearing sand and gravel cushion layer (203) by passing the anchor through the reserved installation hole at the bottom; the paving structure finally formed by the construction process achieves the technical effects of structural stability, ecological and environmental protection, and easy construction and modification.

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