Bridgehead section roadbed capable of weakening differential settlement and construction method of bridgehead section roadbed

Abstract

The invention provides a bridgehead section roadbed capable of weakening differential settlement and a construction method of the bridgehead section roadbed. A bottom plate is poured above a foundation, and bottom ribs matched with the bottom plate in width are arranged in the bottom plate; the ground beams are arranged above the bottom plate, the multiple ground beams extend in parallel in the extending direction of a road, and waste steel rails are arranged in the ground beams; first earthwork standard rooms are laid on the bottom plate and the ground beams, the first earthwork standard rooms are filled with broken stones, and plain soil and lime stabilized soil are laid on the first earthwork standard rooms to serve as a roadbed. The method can be suitable for special geological environments such as goaf areas and karst cave areas, the abandoned sleepers are fully utilized, the ground beams are filled with the abandoned sleepers, the overall stability becomes good, differential settlement of the foundation is weakened, the construction speed is high, the engineering quality is reliable, and the cost is low; the two layers of earthwork standard rooms are adopted, the strength and integrity of the waste sleeper roadbed can be greatly improved, roadbed settlement is reduced, manpower and material resources are saved, and economical efficiency is good.

Description

Technical Field

[0001] The invention belongs to the technical field of road construction, and in particular relates to a bridgehead section roadbed for weakening differential settlement and a construction method thereof. Background Art

[0002] The mined-out area may cause surface subsidence due to the formation of cavities after the underground ore body is mined, affecting the safety of surrounding buildings and infrastructure, while the underground cavities in the karst area may cause the foundation of buildings and roads to be unstable, increasing the risk of damage. In addition, there may be groundwater flow in the karst area, causing water gushing and affecting the stability of the roadbed. Both of these situations will cause uneven roadbed settlement, affecting the flatness and safety of the road.

[0003] Therefore, it is necessary to provide an improved technical solution to address the above-mentioned deficiencies in the prior art. Summary of the invention

[0004] The purpose of the present invention is to overcome the deficiencies in the above-mentioned prior art. The present invention provides a bridgehead section roadbed that weakens differential settlement and a construction method thereof.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] A bridgehead section roadbed for weakening differential settlement, comprising:

[0007] A bottom plate, the bottom plate is cast on the foundation, and bottom ribs matching the width of the bottom plate are arranged inside the bottom plate;

[0008] A ground beam, wherein the ground beam is arranged above the bottom plate, a plurality of the ground beams extend in parallel along the extension direction of the road, and waste rails are arranged inside the ground beams;

[0009] The first geocell is laid on the bottom plate and the ground beam, the first geocell is filled with crushed stone, and plain soil and lime-stabilized soil are laid above the first geocell as a roadbed.

[0010] Preferably, the scrap rails in each of the ground beams are multiple sections, and the joints of the scrap rails in any two adjacent ground beams are staggered;

[0011] A casting template is arranged on the base plate to cast the ground beam and the base plate integrally.

[0012] Preferably, a second geocell is laid under the base plate, the second geocell is filled with crushed stone, and plain soil is provided on both sides of the base plate.

[0013] Preferably, concrete bored piles corresponding to the ground beams are provided on the foundation, the concrete bored piles pass upward through the bottom reinforcement, and the scrap rails are anchored to the upper ends of the concrete bored piles by rigid fasteners.

[0014] Preferably, the concrete bored pile passes through a karst cave below the foundation, and the karst cave is filled by pouring cement, so that the concrete bored pile and the karst cave are cast as one.

[0015] Preferably, abandoned sleepers are laid between two adjacent ground beams, and at least two layers of abandoned sleepers are spaced apart and distributed longitudinally;

[0016] The ground beam is provided with a drainage pipe perpendicular to the extension direction of the road, and the drainage pipe extends outward to the outside of the bottom plate.

[0017] A method for constructing a bridgehead section roadbed for weakening differential settlement comprises the following steps:

[0018] Step S1, leveling the foundation of the bridge head section and measuring and laying out lines above the foundation;

[0019] Step S2, tying bottom reinforcements of a width suitable for the foundation, and laying waste rails corresponding to the ground beams on the bottom reinforcements;

[0020] Step S3, setting up the templates corresponding to the bottom plate and the ground beam, and casting the ground beam and the bottom plate as one;

[0021] Step S4, after the initial setting of the concrete, the formwork is removed, and a first geocell is laid above the bottom plate and the ground beam, the first geocell is filled with crushed stone, and plain soil and lime-stabilized soil are laid above the first geocell as a roadbed;

[0022] Step S5, laying an asphalt concrete surface layer on the roadbed.

[0023] Preferably, in step S1, concrete bored piles corresponding to the ground beams are driven in the corresponding karst cave area of ​​the bridgehead section, and the upper ends of the concrete bored piles extend upward to the bottom reinforcement elevation.

[0024] Preferably, in step S2, a second geocell is laid above the foundation, and the second geocell is filled with crushed stone.

[0025] Preferably, slopes are provided on both sides of the paved plain soil and lime-stabilized soil.

[0026] Beneficial effects: This application can be applied to special geological environments such as goaf areas and karst cave areas, make full use of abandoned sleepers, use abandoned sleepers to fill ground beams, improve overall stability, weaken differential settlement of foundation, fast construction speed, reliable project quality, and low cost; the use of two layers of geocells can greatly improve the strength and integrity of the abandoned sleeper roadbed, reduce roadbed settlement, save manpower and material resources, and is economical. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. Among them:

[0028] Figure 1 A schematic top view of a roadbed in a specific embodiment provided by the present invention;

[0029] Figure 2 It is a simplified cross-sectional view of the roadbed in the specific embodiment provided by the present invention.

[0030] In the figure: 1. ground beam; 2. abandoned rails; 3. concrete piles; 4. abandoned sleepers; 5. base plate; 6. plain soil; 7. asphalt concrete surface layer; 8. lime-stabilized soil; 9. first geocell; 10. second geocell; 11. cave; 12. bottom reinforcement. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention belong to the scope of protection of the present invention.

[0032] In the description of the present invention, the terms "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and do not require that the present invention must be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on the present invention. The terms "connected" and "connected" used in the present invention should be understood in a broad sense. For example, they can be fixed connections or detachable connections; they can be directly connected or indirectly connected through intermediate components. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0033] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments. It should be noted that the embodiments and features in the embodiments of the present invention can be combined with each other without conflict.

[0034] like Figure 1-2As shown, the present application provides a method for constructing a roadbed under special geological conditions such as goaf areas and karst cave areas, specifically comprising a bottom plate 5, a ground beam 1, and a first geocell 9. The bottom plate 5 is cast above the foundation, and the concrete used is C20. The width of the bottom plate 5 is adapted to the width of the foundation. Bottom bars 12 adapted to its width are provided in the bottom plate 5. The bottom bars 12 include mutually perpendicular steel bars, namely, transverse bottom bars 12 of the bottom plate 5 and longitudinal bottom bars 12 of the bottom plate 5. The bottom bars 12 can be multi-layer or single-layer. The ground beam 1 is arranged at There may be multiple ground beams 1 above the base plate 5, and the multiple ground beams 1 extend in parallel along the extension direction of the road. Specifically, there may be three ground beams 1, which are respectively located on both sides and the center of the road. A scrap rail is arranged inside the ground beam 1, and a first geocell 9 is laid on the base plate 5 and the ground beam 1. The first geocell 9 is filled with gravel, and plain soil 6 and lime-stabilized soil 8 are laid above the first geocell 9 as a roadbed, and then an asphalt concrete surface layer 7 is continued to be spread on the roadbed until the predetermined construction elevation is reached to form a bridgehead section roadbed.

[0035] In an optional embodiment, the scrap rails in each ground beam 1 are multiple sections, and the scrap rails can be cut into 8-15 meter long sections. The joints of the scrap rails in any two adjacent ground beams 1 are staggered, and the ground beam 1 and the bottom plate 5 are laid longitudinally, and the scrap rails are also laid longitudinally. A casting template is set on the bottom plate 5 to cast the ground beam 1 and the bottom plate 5 as a whole, thereby improving the stability of the bottom plate 5. In addition to increasing the strength of the bottom plate 5, the ground beams 1 on both sides can also protect the above plain soil 6 and lime-stabilized soil 8, thereby improving the stability of the plain soil 6 and lime-stabilized soil 8.

[0036] In an optional embodiment, a second geocell 10 is laid under the base plate 5, and the second geocell 10 is filled with gravel. Plain soil 6 is provided on both sides of the base plate 5. The height of the plain soil 6 on both sides is higher than the base plate 5 and the ground beam 1 and is set to the same elevation as the plain soil 6 above the base plate 5. Greening is carried out above the plain soil 6 on both sides, and slope protection and greening vegetation are set on the slopes on both sides of the plain soil 6 and lime-stabilized soil 8.

[0037] In an optional embodiment, concrete bored piles 3 corresponding to the ground beams 1 are provided on the foundation, and the concrete bored piles 3 can strengthen the strength of the foundation and prevent the foundation from settling. The concrete bored piles 3 pass upward through the bottom reinforcement 12, and connecting reinforcement can be reserved on the outer wall of the concrete bored piles 3 to connect with the bottom reinforcement 12. The waste rails are anchored to the upper ends of the concrete bored piles 3 by rigid fasteners. The concrete bored piles 3 are arranged in multiple rows, and the multiple rows of concrete bored piles 3 are spaced apart along multiple ground beams 1. Specifically, the distance between two adjacent concrete bored piles 3 on the same ground beam 1 is not greater than the length of each section of the waste rail 2.

[0038] Alternatively, a connecting rib is reserved at the upper end of the concrete pile 3, and after the connecting rib is placed on the abandoned rail 2, the two are fixed by bending and welding.

[0039] In an optional embodiment, geological exploration is carried out before the construction of the concrete bored piles 3. Then, through reasonable arrangement and design of the concrete bored piles 3, the concrete bored piles 3 pass through the karst cave 11 below the foundation and are lowered into the bored pile reinforcement cage. Then, cement can be poured through the pile holes of the bored piles to fill the karst cave 11, so that the concrete bored piles 3 and the karst cave 11 are cast as one, thereby ensuring the stability of the foundation.

[0040] In an optional embodiment, abandoned sleepers 4 are laid between two adjacent ground beams 1, at least two layers of abandoned sleepers 4 are distributed in a longitudinal interval, and multiple arrays are distributed in any layer of abandoned sleepers 4. Any two adjacent abandoned sleepers 4 in the same layer or adjacent layers are connected by iron chains, steel bars or steel cables to form a flexibly connected grid structure, thereby maximizing the deformation resistance of the foundation, so that the foundation has higher stability. A drainage pipe is provided on the ground beam 1 in a direction perpendicular to the extension of the road, and the drainage pipe extends outward to the outside of the bottom plate 5. During the casting process of the ground beam, a drainage pipe passing through the ground beam is pre-buried, so that the seepage water between the two ground beams can be discharged to both sides.

[0041] In this embodiment, the abandoned sleepers 4 are located within 6 layers of plain soil and / or 8 layers of lime-stabilized soil. The 6 layers of plain soil and / or 8 layers of lime-stabilized soil are spread in layers, and then the abandoned sleepers 4 are placed at the designed elevation. Furthermore, the abandoned sleepers 4 on both sides are provided with connecting ribs, which are used to be riveted on the slope protection blocks on the side slopes on both sides, thereby ensuring the stability of the side slopes on both sides. The abandoned sleepers 4 can be arranged longitudinally or extended horizontally. The outer wall of the abandoned sleepers 4 is roughened, and a plurality of sockets are drilled in the axial direction. A part of the sockets is used for installing iron chains, steel bars or steel cables, and another part is used for plugging in square timber, which is carbonized to improve the stability of the abandoned sleepers 4.

[0042] In an optional embodiment, a method for constructing a bridgehead section roadbed that weakens differential settlement includes the following steps: Step S1, after determining the location to be constructed, clean up the discarded sleepers 4 to prevent debris from appearing at the laying location and affecting the stability of the entire roadbed, ensuring that the construction site is clean and tidy; transport the discarded sleepers 4, geocells, gravel and other materials to the construction site, level the foundation of the bridgehead section, and measure and lay out above the foundation to determine the exact position and size of the ground beam 1, thereby completing the preparations before construction.

[0043] Step S2, tie the bottom reinforcement 12 that matches its width to the foundation, and lay the scrap steel rail corresponding to the ground beam 1 above the bottom reinforcement 12, the scrap steel rail is placed flat at the position of the ground beam 1, and its long side direction is the direction of the ground beam 1, fix the scrap steel rail, and each ground beam 1 should be provided with a corresponding scrap steel rail, and the directions of the scrap steel rails are consistent.

[0044] Step S3, set up a concrete pouring template corresponding to the bottom plate 5 and the ground beam 1 on the foundation, and ensure that the template is stable and meets the design requirements, pour concrete into the template, so that the ground beam 1 and the bottom plate 5 are poured as one, and use tools such as vibrators to ensure that the concrete is dense and avoid voids. After the concrete pouring is completed, proper maintenance is carried out to keep the concrete moist and prevent cracking. After the concrete reaches a certain strength, remove the template, check the surface quality of the ground beam 1 and the bottom plate 5, and ensure reliable quality.

[0045] Step S4, after the initial setting of the concrete, the formwork is removed, and the first geocell 9 is laid on the bottom plate 5 and the ground beam 1, and the first geocell 9 is filled with crushed stones, and the first geocell 9 is laid on the first geocell 9 as a roadbed; the first geocell 9 should be close to the upper side of the ground beam 1 and the bottom plate 5, and the first geocell 9 needs to be straightened and smooth, and no distortion or wrinkles should occur. The joints are anchored with U-shaped nails. When the first geocell 9 is laid to the predetermined position, it is backfilled with crushed stones until it is flush with the height of the first geocell 9, and rolled and compacted. The plain soil 6 is laid on the first geocell 9 until it is higher than the height of the ground beam 1 and forms a horizontal surface.

[0046] Step S5, laying an asphalt concrete surface layer 7 on the roadbed, laying a lime stabilization layer and an asphalt concrete surface layer 7 in sequence, forming a road slope of 1:1, and waiting for the construction to be completed, the road can be used smoothly.

[0047] In an optional embodiment, in step S1, concrete bored piles 3 are driven before the foundation construction of the bridgehead section. The concrete bored piles 3 are driven in the cave 11 area, and corresponding to the direction of the ground beam 1, the upper ends of the concrete bored piles 3 extend upward to the elevation of the bottom reinforcement 12, so that the scrap rails and the bottom reinforcement 12 are staggered with each other, thereby forming a three-dimensional steel structure to ensure the stability of the foundation.

[0048] In an optional embodiment, in step S2, the second geocell 10 is first laid at the selected position. The second geocell 10 needs to be straightened and smooth without distortion or wrinkling. U-shaped nails are used for anchoring at the joints. After laying, gravel is backfilled until it is flush with the height of the second geocell 10, and then it is compacted by a roller after manual leveling.

[0049] Side slopes are arranged on both sides of the paved plain soil 6 and the lime-stabilized soil 8, and slope protection blocks are arranged on the side slopes.

[0050] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are within the scope of protection of the pending claims of the present invention.

Claims

1. A bridgehead section roadbed for weakening differential settlement, characterized in that: include: A bottom plate, the bottom plate is cast on the foundation, and bottom ribs matching the width of the bottom plate are arranged inside the bottom plate; A ground beam, wherein the ground beam is arranged above the bottom plate, a plurality of the ground beams extend in parallel along the extension direction of the road, and waste rails are arranged inside the ground beams; The first geocell is laid on the bottom plate and the ground beam, the first geocell is filled with crushed stone, and plain soil and lime-stabilized soil are laid above the first geocell as a roadbed.

2. The bridgehead section roadbed for weakening differential settlement according to claim 1 is characterized in that: The scrap rails in each of the ground beams are multiple sections, and the joints of the scrap rails in any two adjacent ground beams are staggered; A casting template is arranged on the base plate to cast the ground beam and the base plate integrally.

3. The bridgehead section roadbed for weakening differential settlement according to claim 1 is characterized in that: A second geocell is laid under the bottom plate, the second geocell is filled with crushed stones, and plain soil is provided on both sides of the bottom plate.

4. The bridgehead section roadbed for weakening differential settlement according to claim 1 is characterized in that: Concrete piles corresponding to the ground beams are arranged on the foundation, the concrete piles pass through the bottom reinforcement upwards, and the scrap rails are anchored to the upper ends of the concrete piles through rigid fasteners.

5. The bridgehead section roadbed for weakening differential settlement according to claim 4 is characterized in that: The concrete cast-in-place pile passes through the karst cave below the foundation, and the karst cave is filled by pouring cement, so that the concrete cast-in-place pile and the karst cave are cast as one.

6. The bridgehead section roadbed for weakening differential settlement according to claim 1, characterized in that: Abandoned sleepers are laid between two adjacent ground beams, and at least two layers of abandoned sleepers are spaced apart longitudinally; The ground beam is provided with a drainage pipe perpendicular to the extension direction of the road, and the drainage pipe extends outward to the outside of the bottom plate.

7. A method for constructing a bridgehead section roadbed to reduce differential settlement, characterized in that: The following steps are involved: Step S1, leveling the foundation of the bridge head section and measuring and laying out lines above the foundation; Step S2, tying bottom reinforcements of a width suitable for the foundation, and laying waste rails corresponding to the ground beams on the bottom reinforcements; Step S3, setting up the templates corresponding to the bottom plate and the ground beam, and casting the ground beam and the bottom plate as one; Step S4, after the initial setting of the concrete, the formwork is removed, and a first geocell is laid above the bottom plate and the ground beam, the first geocell is filled with crushed stone, and plain soil and lime-stabilized soil are laid above the first geocell as a roadbed; Step S5, laying an asphalt concrete surface layer on the roadbed.

8. The method for constructing a bridgehead section roadbed with weakened differential settlement according to claim 7, characterized in that: In step S1, concrete cast-in-place piles corresponding to the ground beams are driven in the corresponding karst cave area of ​​the bridgehead section, and the upper ends of the concrete cast-in-place piles extend upward to the bottom reinforcement elevation.

9. The method for constructing a bridgehead section roadbed with weakened differential settlement according to claim 7, characterized in that: In step S2, a second geocell is laid on the foundation, and the second geocell is filled with crushed stones.

10. The method for constructing a bridgehead section roadbed with weakened differential settlement according to claim 7, characterized in that: Slopes are set on both sides of the paved plain soil and lime-stabilized soil.

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