A roadbed construction method suitable for widening and reconstruction of existing highway

Abstract

This application provides a roadbed construction method applicable to existing highway widening and reconstruction projects, relating to the field of highway widening and reconstruction. It includes: stepped excavation treatment: excavating in stages along the widening side of the existing roadbed to form a stepped connection zone, and laying an interface geogrid on the stepped surface; layered reverse-wrapping reinforced filling: compacting the fill material, folding the interface geogrid back into the fill body to form an inner reverse-wrapping reinforced fill body; assembling the outer segmented wall: hoisting and vertically splicing the prefabricated outer segmented wall; laying a composite drainage system; assembling the top capping components; installing the top tension restraint structure: laying a top tension geogrid, connecting the two ends to the outer segmented wall via adjustable connecting components; pre-tensioning and locking the top tension geogrid, pouring and shaping the top surface of the roadbed, connecting to the existing pavement, and removing construction auxiliary components to complete the construction. This application has the effect of reducing the risk of differential settlement and shear slippage.

Description

Technical Field

[0001] This application relates to the field of highway widening and reconstruction technology, and in particular to a roadbed construction method applicable to existing highway widening and reconstruction projects. Background Technology

[0002] Widening and reconstructing existing highways is not simply a matter of widening the roadbed; the key lies in achieving coordinated stress distribution and deformation between the newly constructed and widened roadbed and the existing roadbed. The existing roadbed bears traffic loads over a long period and undergoes natural consolidation, resulting in significant differences in density, stiffness, settlement state, and stress history compared to the newly constructed widened roadbed. Conversely, the newly constructed widened roadbed is still in the stress adjustment and compaction deformation stage during construction and the initial service period, making it prone to additional settlement and lateral deformation. Therefore, the junction between the old and new roadbeds often experiences abrupt changes in stiffness, inconsistent settlement, shear slippage, and stress concentration, which in turn induces longitudinal cracks, changes in cross slope, shoulder cracking, misalignment at the junction, and reduced overall embankment stability, affecting the driving comfort, safety, and long-term durability of the widened highway.

[0003] Currently, existing highway widening projects often employ measures such as slope cutting and excavation, stepping treatment, layered filling and compaction, laying geogrids, and constructing retaining walls or reinforced soil retaining walls to enhance the connection between the old and new roadbeds and control differential settlement. Among these, stepping treatment can improve the interlocking effect at the interface between the old and new roadbeds; geogrids can improve the overall integrity of the fill through a reinforcing effect; and retaining walls or reinforced soil retaining walls can, to some extent, address the issues of insufficient widening space and external support. While these measures are effective under conventional widening conditions, they still have shortcomings in complex situations such as construction with continuous traffic flow, widening on slopes in mountainous areas, large fill heights, or limited external space.

[0004] On the one hand, traditional methods of widening roadbeds and reinforcing them mainly rely on laying geogrids. This reinforcement primarily depends on the interfacial friction and tensile stiffness between the geogrid and the fill material, offering limited constraint on lateral deformation of the fill. When the widened fill is subjected to vehicle loads, filling loads, and rainwater infiltration, the reinforced structure struggles to effectively contain and constrain the fill material, easily leading to lateral bulging deformation on the outer side of the widened roadbed and further exacerbating vertical settlement and deformation inconsistencies at the junction of the old and new roadbeds. On the other hand, existing roadbed widening projects are often constrained by road boundaries, adjacent structures, slope topography, and traffic organization conditions, making it difficult to employ large-slope or large-scale excavation methods. While traditional rigid retaining structures offer strong lateral support, their high rigidity makes them prone to abrupt deformations between the rigid wall and the flexible fill, hindering long-term coordinated deformation between the old and new roadbeds. Furthermore, rigid retaining walls typically require large foundation excavation spaces, resulting in significant construction disturbances that fail to meet the requirements of low-disturbance, rapid, and safe construction for existing highways. Conversely, conventional reinforced soil retaining wall structures suffer from insufficient overall synergy between the wall surface, the reinforced structure, and the existing roadbed. Under loads on the top of the wall, traffic loads, and rainwater infiltration, problems such as wall bulging, top cracking, concentrated localized deformation of the reinforced structure, and persistent differential settlement of the roadbed may still occur.

[0005] Furthermore, drainage and deformation control are also prominent issues in existing roadbed widening projects. The outer side of the widened roadbed is usually a newly filled area, and the compaction quality of the fill material, interface drainage conditions, and rainwater infiltration paths significantly affect its long-term stability. If the drainage system is inadequate, rainwater can easily seep in along the interface between the old and new roadbeds or the back wall area, leading to reduced fill material strength, decreased interfacial friction of the geogrid, and accumulation of pore water pressure, thereby weakening the anti-slip capacity and overall stability of the widened roadbed. Existing widening measures often design reinforcement, support, drainage, and construction auxiliary measures separately, lacking an integrated structural system that addresses the coordinated stress distribution between the old and new roadbeds, differential settlement control, and lateral stabilization support. Summary of the Invention

[0006] In order to overcome the technical problems described in the prior art, this application provides a roadbed construction method applicable to the widening and reconstruction of existing highways.

[0007] This application provides a roadbed construction method applicable to existing highway widening and reconstruction projects, which adopts the following technical solution: A roadbed construction method applicable to existing highway widening and reconstruction projects includes the following steps: S1. Step excavation treatment: The existing roadbed is widened in stages to form a stepped connection area. Interface geogrid is laid on the step surface, and the interface geogrid bridges the existing roadbed and the widened filling area. S2, Layered Reinforced Filling: The fill material is laid and compacted in layers, and the interface geogrid laid in each layer is folded back into the fill body to form a continuously wrapped inner reinforced fill body. S3. Synchronous assembly of the outer segmented wall: The prefabricated outer segmented wall is hoisted and vertically spliced ​​during the filling and construction. The wall back drainage layer and filter layer of the composite drainage system are laid simultaneously on the back of the wall. S4. Install a composite drainage system: Drainage boards, blind ditches, and drainage components are installed at the junction of the new and old roadbeds, inside the fill body, and on the outer segmented wall to form a continuous drainage channel. S5. Assemble the top coping components of the wall; S6. Install the top tension restraint structure: Lay the top tension geogrid, and connect the two ends to the outer segmented wall surfaces on both sides through adjustable connecting components. S7. Pre-tensioned and locked top tension geogrid, adjustable connecting components with reserved sliding and rotation allowance to adapt to differential settlement, pouring and shaping the top surface of the subgrade, connecting to the original pavement and removing construction auxiliary components to complete the construction.

[0008] Furthermore, in step S1, the interface geogrid is fixed to the stepped connection area by means of burying and anchoring trenches, and the stepped connection area, the interface geogrid, and the filler form a composite anti-slip interface.

[0009] Furthermore, in step S2, the geogrid back-wrap structure of each layer interface is connected horizontally and continuously, forming an inner back-wrap reinforced fill body.

[0010] Furthermore, in step S3, the blocks of the outer segmented wall are vertically connected by steel rods and plug-in rods.

[0011] Furthermore, in step S3, a hanging structure is set on the back of the outer segmented wall surface, which is flexibly connected to the inner reverse-wrap reinforced filling body through the hanging structure.

[0012] Furthermore, in step S5, the top capping component is a cast-in-place beam, a precast capping block, or an assembled composite beam, arranged along the entire length of the outer segmented wall surface.

[0013] Furthermore, in step S3, the composite drainage system integrates a top reverse filter drainage layer, a wall-back drainage layer, a horizontal blind drain, and wall-mounted drainage components.

[0014] Furthermore, in step S6, the adjustable connecting component includes a clamping steel plate, a turnbuckle, a rotary joint, and an elastic buffer layer. The clamping steel plate is fixedly installed on the outer segmented wall by bolts. The elastic buffer layer is pressed between the clamping steel plate and the outer segmented wall. One end of the turnbuckle is welded and fixed to the clamping steel plate, and the other end is fixedly connected to the top tie-down geogrid through the rotary joint.

[0015] Furthermore, in step S7, during the construction phase, the pre-tightening force of the top tension geogrid is adjusted by the adjustable connecting components, and during the operation phase, the deformation is reserved by the elastic buffer layer to simultaneously achieve the coordination of tie-in limit and settlement deformation.

[0016] Furthermore, in step S7, the construction auxiliary components include disassembly and assembly brackets, grid guides, wall positioning components, and layer thickness control components, which are used for positioning, support, and correction throughout the construction process and can be disassembled after construction is completed.

[0017] In summary, this application includes at least one of the following beneficial technical effects: 1. This invention combines the existing roadbed stepped connection zone with the inner reverse-wrapped reinforced filling body to form a composite connection system between the old and new roadbeds, which has the combined effects of interlocking, friction, ties and wrapping constraints. This can effectively improve the stress transmission path at the joint between the old and new roadbeds and reduce the risk of differential settlement and shear slip. 2. This invention uses an inner reverse-wrapping reinforcement structure to wrap and constrain the widened fill layer by layer, transforming the widened fill into a reinforced fill with internal continuous ties and lateral restraint capabilities, thereby improving its integrity, resistance to lateral deformation, and adaptability to uneven settlement. 3. This invention provides lateral support for widening the roadbed through the outer segmented wall surface. At the same time, the segmented structure reduces the sudden change in wall stiffness and construction difficulty, so that the wall structure has sufficient support capacity and can adapt to the local deformation requirements during the construction and service period of the widened roadbed. 4. This invention uses a top-pull geogrid and adjustable connecting components to connect the outer segmented wall, the inner reverse-wrapping reinforcement structure, and the widened fill into a synergistic force-bearing system. This can limit the outward movement of the wall, disperse lateral earth pressure, reduce local stress concentration, and improve the deformation coordination ability of the overall structure.

[0018] 5. This invention combines wall-back drainage, internal drainage, reverse filtration and anti-clogging, and top drainage through a composite drainage system, which can reduce the adverse effects of rainwater infiltration on the strength of the filler and the performance of the reinforced interface, reduce the accumulation of pore water pressure, and thus improve the hydraulic stability and durability of the widened roadbed during long-term service. 6. This invention enables the positioning and installation of wall sections, reinforcing materials, tie rods, and drainage components through modular construction auxiliary components. This reduces construction deviations, improves construction efficiency, and minimizes disturbance to existing roadbeds and traffic flow. It is suitable for complex engineering conditions such as continuous traffic flow, limited construction space, and widening of slopes in mountainous areas. Attached Figure Description

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

[0020] Figure 1 This is a schematic diagram of the widening of an existing roadbed in an embodiment of this application.

[0021] Figure 2 This is a schematic diagram showing the connection between the inner inverted reinforced filling body and the outer segmented wall surface in an embodiment of this application.

[0022] Figure 3 This is a schematic diagram of the connection between the top-pull geogrid and the adjustable connecting member in an embodiment of this application.

[0023] Reference numerals: 1. Existing roadbed; 2. Stepped connection zone; 3. Inner-side reinforced fill; 4. Outer-side segmented wall; 5. Composite drainage system; 6. Top capping component; 7. Top tension geogrid; 8. Adjustable connection component; 81. Clamping steel plate; 82. Turnbuckle; 83. Rotary joint; 84. Elastic buffer layer; 9. Hanging structure. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0025] This application discloses a roadbed construction method applicable to the widening and reconstruction of existing highways. (Refer to...) Figure 1 , Figure 2 and Figure 3 A roadbed construction method applicable to existing highway widening and reconstruction projects includes the following steps: S1. Step excavation treatment: Along the existing roadbed 1, the side slope is widened and multi-level steps are excavated from top to bottom. Weeds and loose soil on the step slope are cleared, and the steps are leveled and compacted to form a stepped connection area 2.

[0026] The interface geogrid is laid horizontally across the steps, with half of the interface geogrid laid flat and buried within the surface of the existing roadbed step 1, and the other half extending outward to the widened filling area; the interface geogrid is fixed by anchoring trench burial method, and shallow anchoring trenches are excavated along the inner side of the steps, with the ends of the interface geogrid folded back into the trench, backfilled with plain soil, compacted and locked.

[0027] The stepped connection zone 2, the interface geogrid, and the widened fill material form a composite anti-slip interface with stepped interlocking, geogrid bonding, and interface friction synergy. When the widened subgrade shows a tendency to slide along the interface between the old and new subgrades, the interface geogrid can convert the sliding shear force into the tension of the geogrid itself and the interface friction force between the geogrid and the fill material, thus constraining the relative shear displacement of the old and new subgrades and suppressing the joint misalignment and longitudinal cracks from the source.

[0028] S2, Layered Reinforced Filling: After the interface geogrid is laid to the outer edge of the widened fill body, the subgrade fill material is laid in layers and compacted to the designed compaction degree using a vibratory roller. After each layer of fill material is laid, the interface geogrid is folded back into the fill body to form a reverse wrapping structure, and then the next layer of fill material is laid to cover the reverse wrapping section and compacted simultaneously.

[0029] The geogrids at each interface form a continuous, transversely connected structure along the road, with overlapping spaces between upper and lower layers, forming a continuous, internally wrapped, reinforced fill body 3. The construction process is coherent, with each layer of fill material forming a wrapping constraint, significantly improving the overall integrity, tensile strength, and resistance to lateral expansion deformation of the fill body, providing a stable internal load-bearing foundation for the outer segmented wall 4 and the top tension constraint structure.

[0030] S3, Synchronous assembly of the outer segmented wall panel 4: Precast outer segmented wall panels 4 are hoisted simultaneously with the layered filling. Steel rods are used as vertical connectors between adjacent upper and lower wall panels. These rods pass through pre-drilled vertical holes in the wall panels, ensuring continuous longitudinal stress on the wall. The vertical connecting rods allow for minute rotations and displacements between the wall panels within a defined range, accommodating the compaction deformation of the fill material and the differential settlement between the old and new roadbeds, thus preventing stress concentration and cracking of the rigid, monolithic wall.

[0031] In this embodiment, the pre-embedded hanging structure 9 on the back of the outer segmented wall 4 is a ring installed on the back of the outer segmented wall 4 and a hook-shaped steel bar that is rotatably hung on the ring. During subsequent construction, the hook-shaped steel bar is flexibly connected to the interface geogrid in the inner reverse-wrap reinforced fill body 3, which can transmit lateral earth pressure and adapt to small relative displacements between the outer segmented wall 4 and the inner reverse-wrap reinforced fill body 3.

[0032] The outer segmented wall 4 is assembled simultaneously with the wall back drainage layer and geotextile filter layer of the composite drainage system 5. The drainage layer is filled with graded crushed stone, and the filter layer wraps the crushed stone to prevent fine particles from the roadbed from blocking the drainage channel.

[0033] S4. Install a composite drainage system 5: The composite drainage system 5 is composed of a top reverse filter drainage layer, a wall-back drainage layer, horizontal drainage blind ditches, and wall-side drainage components. A top reverse filter drainage layer, consisting of plastic drainage boards and geotextile filter cloth, is laid on top of the junction of the new and old roadbeds to intercept and filter rainwater and surface runoff from the road surface, preventing rainwater from seeping down along the junction of the new and old roadbeds and softening the fill material. A layer of horizontal crushed stone blind ditches is set at certain heights inside the widened fill body, and the blind ditches are connected to the wall-back drainage layer. The bottom of the outer segmented wall 4 is reserved with circular drainage holes as drainage components, and all drainage structures are interconnected to form a through drainage channel.

[0034] The composite drainage system 5 can quickly drain seepage water from the backfill, wall back, and the interface between new and old materials, reduce pore water pressure in the subgrade, prevent the strength of the fill material from decaying, reduce the interface friction of the geogrid, and improve the long-term hydraulic stability of the subgrade.

[0035] S5, Assemble the top coping component of the wall: After the roadbed is filled to the design subbase elevation, a coping component 6 is installed along the entire length of the top of the outer segmented wall 4. The coping component 6 can be a cast-in-place beam, a precast coping block, or a prefabricated composite beam. In this embodiment, a precast reinforced concrete coping block is selected, with adjacent coping blocks tightly spliced ​​and continuously arranged along the longitudinal direction of the road. The coping component 6 can disperse the concentrated tensile stress transmitted by the top tension geogrid 7, preventing local pressure damage to the top of the wall, and at the same time providing a stable installation base for the adjustable connecting component 8.

[0036] S6. Install the top tension restraint structure: A top-pull geogrid 7 is laid under the top capping component 6. The top-pull geogrid 7 spans the deformation-sensitive area above the roadbed and the two ends of the top-pull geogrid 7 are fixed to the top of the outer block wall 4 on both sides by adjustable connecting components 8.

[0037] The adjustable connecting component 8 is assembled from a clamping steel plate 81, turnbuckles 82, a rotary joint 83, and an elastic buffer pad 84. The elastic buffer pad can be a damping pad, rubber pad, etc. The clamping steel plate 81 is locked and fixed to the top of the outer segmented wall 4 with high-strength bolts. The elastic buffer pad 84 is pressed and arranged between the clamping steel plate 81 and the wall. One end of the turnbuckle 82 is welded and fixed to the clamping steel plate 81, and the other end is tied and fixed to the end of the top tension geogrid 7 through the rotary joint 83. The entire component achieves a reliable and flexible connection between the top tension geogrid 7 and the outer wall.

[0038] S7, Pre-tensioned and locked top tension geogrid 7: During the construction phase, pre-tensioning force can be applied to the top tension geogrid 7 using turnbuckles 82 and the geogrid can be locked and limited. The top surface of the roadbed can then be poured and shaped to connect with the existing road surface. After the roadbed is formed as a whole, all construction auxiliary components are removed, including dismantling and assembling construction supports, geogrid laying guides, wall positioning components, and layer thickness control components. The construction auxiliary components are used throughout the geogrid laying and wall assembly stages to control the elevation, alignment, and layer thickness. After removal, they do not occupy roadbed structural space and do not affect the long-term load-bearing capacity of the roadbed.

[0039] During highway operation, differential settlement occurs between the old and new roadbeds. When this differential settlement causes tension on the top tension geogrid 7, the clamping steel plate 81 will compress and partially push against the outer segmented wall 4. The elastic buffer layer 84 is compressible, and at the pressure point of the clamping steel plate 81, the elastic buffer layer 84 undergoes elastic compression deformation, increasing the contact area between the clamping steel plate 81 and the outer segmented wall 4, dispersing localized concentrated compressive stress, and preventing localized pressure-bearing cracking of the outer segmented wall 4. After the load disappears, the elastic buffer layer 84 rebounds and returns to its initial clamping state. The differential settlement between the old and new roadbeds will cause the top tension geogrid 7 to have a tendency to slide laterally / longitudinally, causing the clamping steel plate 81 to slightly shift relative to the outer segmented wall 4. The elastic buffer layer 84 can undergo shear deformation, allowing the clamping steel plate 81 to slide slightly, offsetting the additional shear force transmitted from the top tension geogrid 7, and preventing the shear force from acting directly on the wall bolts and concrete surface. Repeated vehicle loads and slow long-term settlement of the roadbed result in cyclical alternating stress at the nodes. The internal polymer materials of the damping pads and rubber pads have internal friction. When the steel plate 81 is repeatedly squeezed and the pad layer is moved, the pad layer converts the additional stress generated by settlement and vehicle vibration into heat energy dissipation through internal material friction, avoiding the continuous accumulation of stress and preventing stress fatigue damage to the wall, grid, and turnbuckle 82 connection parts.

[0040] After construction using this method, the stepped connection zone 2, the interface geogrid, the inner reinforced fill 3, the outer segmented wall 4, the top capping component 6, the top tension geogrid 7, the adjustable connection component 8, and the composite drainage system 5 form an integrated composite stability system. Within a narrow widening space, this method simultaneously achieves: anti-slip properties at the interface between the old and new roadbeds, internal containment of the fill material, flexible external support, top lateral restraint, adaptive adjustment of differential settlement, and comprehensive seepage prevention and drainage—multiple synergistic effects. This significantly reduces longitudinal cracking at the junction of the old and new roadbeds, roadbed misalignment, wall bulging and slippage, and other defects. It is suitable for complex widening conditions such as mountainous slopes, restricted right-of-way, and continuous traffic flow. The construction process is continuous, with minimal on-site disturbance and lower overall cost.

[0041] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for roadbed construction applicable to existing highway widening and reconstruction projects, characterized in that, Includes the following steps: S1. Step excavation treatment: The existing roadbed is widened in stages to form a stepped connection area. Interface geogrid is laid on the step surface, and the interface geogrid bridges the existing roadbed and the widened filling area. S2, Layered Reinforced Filling: The fill material is laid and compacted in layers, and the interface geogrid laid in each layer is folded back into the fill body to form a continuously wrapped inner reinforced fill body. S3. Synchronous assembly of the outer segmented wall: The prefabricated outer segmented wall is hoisted and vertically spliced ​​during the filling and construction. The wall back drainage layer and filter layer of the composite drainage system are laid simultaneously on the back of the wall. S4. Install a composite drainage system: Drainage boards, blind ditches, and drainage components are installed at the junction of the new and old roadbeds, inside the fill body, and on the outer segmented wall to form a continuous drainage channel. S5. Assemble the top coping components of the wall; S6. Install the top tension restraint structure: Lay the top tension geogrid, and connect the two ends to the outer segmented wall surfaces on both sides through adjustable connecting components. S7. Pre-tensioned and locked top tension geogrid, adjustable connecting components with reserved sliding and rotation allowance to adapt to differential settlement, pouring and shaping the top surface of the subgrade, connecting to the original pavement and removing construction auxiliary components to complete the construction.

2. The method for roadbed construction applicable to the widening and reconstruction of existing highways according to claim 1, characterized in that, In step S1, the interface geogrid is fixed to the stepped connection area by burying and anchoring trenches. The stepped connection area, the interface geogrid, and the filler form a composite anti-slip interface.

3. The method for roadbed construction applicable to the widening and reconstruction of existing highways according to claim 1, characterized in that, In step S2, the geogrid back-wrap structure of each layer is connected horizontally and continuously, forming an inner back-wrap reinforced fill body.

4. The method for roadbed construction applicable to the widening and reconstruction of existing highways according to claim 1, characterized in that, In step S3, the blocks of the outer segmented wall are vertically connected by steel rods and plug-in rods.

5. A roadbed construction method applicable to existing highway widening and reconstruction projects according to claim 1, characterized in that, In step S3, a hanging structure is set on the back of the outer segmented wall surface, and the hanging structure is flexibly connected with the inner reverse-wrapped reinforced filling body.

6. The method for roadbed construction applicable to the widening and reconstruction of existing highways according to claim 1, characterized in that, In step S5, the top capping component is a cast-in-place beam, a precast capping block, or an assembled composite beam, arranged along the entire length of the outer segmented wall surface.

7. A roadbed construction method applicable to existing highway widening and reconstruction projects according to claim 1, characterized in that, In step S3, the composite drainage system integrates the top reverse filter drainage layer, the wall-back drainage layer, the horizontal blind ditch, and the wall surface drainage components.

8. A roadbed construction method applicable to existing highway widening and reconstruction projects according to claim 1, characterized in that, In step S6, the adjustable connecting component includes a clamping steel plate, a turnbuckle, a rotary joint, and an elastic buffer layer. The clamping steel plate is fixedly installed on the outer segmented wall by bolts. The elastic buffer layer is pressed between the clamping steel plate and the outer segmented wall. One end of the turnbuckle is welded and fixed to the clamping steel plate, and the other end is fixedly connected to the top tie-down geogrid through the rotary joint.

9. A method for roadbed construction applicable to the widening and reconstruction of existing highways according to claim 8, characterized in that, In step S7, during the construction phase, the pre-tightening force of the top tension geogrid is adjusted by the adjustable connecting components. During the operation phase, the deformation is reserved by the elastic buffer layer, so as to simultaneously achieve the coordination of tie limit and settlement deformation.

10. A method for roadbed construction applicable to the widening and reconstruction of existing highways according to claim 1, characterized in that, In step S7, the construction auxiliary components include disassembly and assembly brackets, grid guides, wall positioning components, and layer thickness control components, which are used for positioning, support, and correction throughout the construction process and can be disassembled after construction is completed.

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