Roadbed structure of expressway crossing goaf and construction method of roadbed structure

Abstract

The invention belongs to the technical field of road construction, and particularly relates to a roadbed structure of an expressway penetrating through a goaf and a construction method of the roadbed structure. The roadbed structure comprises a first waterproof layer, a roadbed and a stable soil layer, the roadbed comprises a concrete bottom plate, concrete side plates, partition plates, beams and earthwork standard rooms. The partition plates are arranged in an area defined by the concrete bottom plate and the concrete side plates, and first filler is arranged between the partition plates or between the partition plates and the concrete side plates. The beam is arranged above the partition plate and / or the concrete side plate, and the periphery and the upper portion of the beam are filled with second filler; the geocell is arranged above the second filler in the area defined by the corresponding concrete side plates and the concrete bottom plate, and the geocell is filled with third filler. The roadbed structure can effectively solve the problems of local pressure concentration and differential settlement caused by underground cavities existing in the goaf, so that the roadbed has higher adaptability in the aspects of bearing capacity and stability.

Description

Technical Field

[0001] The invention belongs to the technical field of road construction, and in particular relates to a roadbed structure of a highway passing through a goaf and a construction method thereof. Background Art

[0002] Nowadays, highways have different roadbed filling materials, such as soil-rock mixed filling materials, gravel-soil filling materials, etc., which can effectively improve the road's carrying capacity, ensure the driving of vehicles on the road, and extend the life of the road to a certain extent. However, there are few attempts to use solid waste materials as roadbed filling materials, and highway roadbeds based on calcium carbonate are almost non-existent, and the specific construction method needs to be improved urgently; in addition, calcium carbonate is a solid waste material. Large amounts of accumulation will not only occupy land, but also harm the surrounding environment and affect people's health.

[0003] Goaf refers to the hollow area left after underground coal mining, which usually appears as a void or collapse area in the stratum. In highway construction, the existence of goaf will bring a series of potential safety risks and engineering problems. Goaf will lead to unstable foundation, which will cause road surface settlement or collapse, seriously affecting the flatness and safety of highway. Goaf will also lead to insufficient soil bearing capacity, affect the compaction and stability of the roadbed, and increase the risk of road cracking and deformation. In addition, goaf may also cause abnormal groundwater flow, further damage the roadbed structure, and even affect the long-term performance of transportation facilities.

[0004] Therefore, it is necessary to provide an improved technical solution to address the above-mentioned deficiencies in the prior art. Summary of the invention

[0005] The object of the present invention is to provide a roadbed structure for a highway passing through a goaf area and a construction method thereof, so as to help solve or improve at least one of the problems of road surface settlement, cracking and poor long-term performance that are prone to occur in goaf area highways.

[0006] In order to achieve the above-mentioned purpose, the present invention provides the following technical solutions: a roadbed structure of a highway passing through a goaf, comprising a first waterproof layer, a roadbed and a stabilized soil layer arranged in sequence from bottom to top; the roadbed comprises a concrete bottom plate, a concrete side plate, a partition, a beam and a geocell; the concrete side plate is arranged on the side of the concrete bottom plate; the partition is arranged in the area surrounded by the concrete bottom plate and the concrete side plate, and a first filler is arranged between the partitions or between the partition and the concrete side plate, and the first filler is a mixture of calcium carbonate and expansive soil; the beam is arranged above the partition and / or the concrete side plate, and a second filler is arranged around and above the beam; the geocell is arranged above the second filler in the area surrounded by the corresponding concrete side plate and the concrete bottom plate, and a third filler is arranged in the geocell.

[0007] Preferably, a second waterproof layer and / or a thermal insulation layer is provided between the concrete side plate and the first filler; and the second waterproof layer is provided between the concrete side plate and the thermal insulation layer.

[0008] Preferably, the second filler is plain soil; and the third filler is crushed stone.

[0009] Preferably, the thickness of the concrete bottom plate and / or concrete side plate is 30 cm; the thickness of the partition plate is 20 cm; and the partition plate is sealed and connected to the concrete bottom plate.

[0010] The present invention also provides a construction method for the subgrade structure of a highway passing through a goaf as described above, which adopts the following technical scheme: The construction method for the subgrade structure of a highway passing through a goaf as described above comprises the following steps: (1) preparation before construction; (2) laying the first waterproof layer; (3) pouring the concrete base plate; (4) installing the concrete side plates; (5) installing the partition plate in the area enclosed by the concrete base plate and the concrete side plates; (6) filling the first filler into the area enclosed by the concrete base plate and the concrete side plates; (7) arranging a beam above the concrete side plates and / or the partition plate, and filling a second filler around and above the beam; (8) arranging a geocell above the second filler inside the area enclosed by the corresponding concrete side plates and the concrete base plate, and filling the geocell with a third filler; (9) laying a stable soil layer above the geocell.

[0011] Preferably, the method further comprises the step of installing a second waterproof layer and / or a thermal insulation layer on the inner side of the concrete side slab.

[0012] Preferably, after the concrete base plate is cast, it is vibrated, smoothed and cured; when the partition is installed, the sealing between the partition and the concrete base plate is ensured.

[0013] Preferably, when filling the first filler, firstly mix the calcium carbonate and the expansive soil evenly, then use a grader to shape them, and after shaping, use a roller to compact them within the full width; after compaction, the first filler is cured, and the curing time of the first filler is 14 days.

[0014] Preferably, after the second filler is filled until it is uniform and flat, it is compacted; when setting the geocell, the geocell needs to be straightened and smoothed, close to the lower surface, and anchored with U-shaped nails at the joints. After the anchoring is completed, the third filler is filled.

[0015] Beneficial effects:

[0016] In the roadbed structure of the expressway passing through the goaf of the present invention, the arrangement of the concrete bottom plate, concrete side plates, partitions and beams enables the entire roadbed part to form a supporting foundation, greatly improving the rigidity and stability and not easy to collapse; the partition is used to separate the first filler, which can not only ensure that each part of the calcium carbonate reacts fully with the expansive soil, but also provide support for the highway to avoid uneven settlement; the arrangement of the geocell helps to strengthen the roadbed structure and disperse the load, and the upper load is transferred to the deeper roadbed by laying the geocell, effectively reducing the local pressure concentration caused by underground cavities or uneven settlement; calcium carbonate and expansive soil are mixed as the first filler to form a roadbed material with high strength and stability, maintaining the flatness and strength of the roadbed.

[0017] In the roadbed structure of the expressway passing through the goaf of the present invention, the provision of the thermal insulation layer and the second waterproof layer can adjust the temperature and humidity changes; wherein, the thermal insulation layer can slow down the temperature difference change, avoid frost heave or thermal expansion and contraction caused by seasonal changes, and in cold areas, it can effectively isolate the external low temperature, avoid frost heave of the roadbed, and reduce cracks and settlement caused by temperature changes; the second waterproof layer helps to solve the problem of groundwater infiltration in the goaf, and prevents the erosion of groundwater to the soil and roadbed materials through the second waterproof layer, protects the completion of the chemical reaction of calcium carbonate and expansive soil, improves the water permeability resistance of the roadbed, and ensures the long-term stability of the soil. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] 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:

[0019] Figure 1 A cross-sectional view of a roadbed structure of a highway passing through a goaf provided by an embodiment of the present invention;

[0020] Figure 2 A top view of a roadbed structure of a highway passing through a goaf before geocells are installed, provided in one embodiment of the present invention.

[0021] Reference numerals:

[0022] 1-first waterproof layer; 2-concrete bottom plate; 3-concrete side plate; 4-partition; 5-second waterproof layer; 6-insulation layer; 7-first filler; 8-beam; 9-second filler; 10-third filler; 11-geocell; 12-stable soil layer; 13-surface layer; 14-void; 15-foundation. DETAILED DESCRIPTION

[0023] 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.

[0024] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., and orientations or positional relationships indicated are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0025] In the description of the present invention, "several" means one or more, "more" means more than two, "greater than", "less than", "exceed" etc. are understood as not including the number itself, and "above", "below", "within" etc. are understood as including the number itself. If there is a description of "first" or "second", it is only used for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0026] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more features.

[0027] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense, for example, it can be a fixed connection or a movable connection, a detachable connection or a non-detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or mutual communication; it can be a direct connection, or an indirect connection through an intermediate medium, and it can be the internal connection of two elements, the indirect connection, or the interaction relationship between two elements.

[0028] The present invention will be described in detail below in conjunction 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.

[0029] Aiming at at least one of the problems of road surface settlement, cracking and poor long-term performance existing in existing expressways in goaf areas, the present invention provides a roadbed structure for expressways passing through goaf areas.

[0030] like Figure 1-2As shown, the subgrade structure of the expressway passing through the goaf of the embodiment of the present invention comprises a first waterproof layer 1, a roadbed and a stabilized soil layer 12 arranged in sequence from bottom to top; the roadbed comprises a concrete bottom plate 2, a concrete side plate 3, a partition 4, a beam 8 and a geocell 11; the concrete side plate 3 is arranged on the side of the concrete bottom plate 2; the partition 4 is arranged in the area surrounded by the concrete bottom plate 2 and the concrete side plate 3, and a first filler 7 is arranged between the partitions 4 and the partitions 4 or between the partitions 4 and the concrete side plates 3, and the first filler 7 is a mixture of calcium carbonate and expansive soil; the beam 8 is arranged above the partition 4 and / or the concrete side plate 3, and a second filler is arranged around and above the beam 8; the geocell 11 is arranged above the second filler 9 in the area surrounded by the corresponding concrete side plate 3 and the concrete bottom plate 2, and a third filler 10 is arranged in the geocell 11. Among them, the beam 8 in the present invention can play a role in supporting and enhancing the overall rigidity and bearing capacity of the roadbed.

[0031] In the roadbed structure of the expressway passing through the goaf of the present invention, the provision of the first waterproof layer 1 can prevent the penetration of groundwater in the goaf, thereby helping to ensure the overall strength and stability of the road; the structure composed of the concrete bottom plate 2, the concrete side plate 3, the partition plate 4, the first filler 7 and the beam 8 can form the supporting foundation of the expressway passing through the goaf, greatly improving the rigidity and stability of the road surface structure, and can effectively solve the goaf ( Figure 1 In the embodiment, the local pressure concentration and uneven settlement caused by the underground cavities existing in the goaf (by arranging the cavities 14 on the foundation 15 to simulate the goaf) are eliminated, so that the roadbed has stronger adaptability in terms of bearing capacity and stability. In addition, the first filler 7 filled between the concrete bottom plate 2, the concrete side plate 3 and the partition plate 4 is a mixture of calcium carbonate and expansive soil, which can have sufficient strength after curing (calculated lime reacts with water to generate calcium hydroxide, and the reaction releases heat, so that calcium carbonate and expansive soil form a dense structure), and can provide sufficient bearing capacity.

[0032] Preferably, the beam 8 is arranged perpendicular to at least a portion of the concrete side panels 3 and / or the partitions 4 (e.g. Figure 2 The beam 8 is connected to the concrete side plate 3 and / or the partition plate 4 by means of steel bar binding.

[0033] More preferably, the beam 8 can be a cast-in-place beam (a mold is built and concrete is poured at the construction site according to the structural design), or a prefabricated beam (reinforced concrete component). Further preferably, the beam 8 is a rectangular beam, which has good bearing capacity and stability.

[0034] The present invention adopts a roadbed structure composed of a concrete bottom plate 2, a concrete side plate 3, a partition 4, a first filler 7 and a beam 8. The overall stability and bearing capacity of the roadbed are enhanced by arranging beams 8 and partitions 4. Compared with a structure in which the partitions 4 and beams 8 are replaced by a top plate, the present invention is more suitable for expressways in goaf areas. This is because the use of a top plate will cause a greater structural burden, and the soil layer in the goaf is often uneven and complex. The use of a top plate may increase the risk of settlement or cause structural deformation. The roadbed structure composed of a concrete bottom plate 2, a concrete side plate 3, a partition 4, a first filler 7 and beams 8 can better transfer the load to a deeper roadbed layer, thereby preventing roadbed collapse caused by underground cavities in the goaf and uneven settlement. Specifically, the beam 8 can transfer the load, especially in the uneven geological environment such as the goaf, the beam 8 can help to evenly distribute the load of the upper layer to the lower foundation, avoiding local pressure concentration caused by underground cavities and uneven settlement; the partition 4 not only helps to separate the mixed area of ​​the first filler 7 and prevent the mixed layer from being disturbed by the outside, but also can effectively control the hierarchical structure of the reaction between the calcium carbonate and the expansive soil in the first filler 7; the partition 4 also plays a role in enhancing the overall rigidity.

[0035] In the preferred embodiment of the roadbed structure of the expressway passing through the goaf of the present invention, a second waterproof layer 5 and / or a thermal insulation layer 6 are arranged between the concrete side plate 3 and the first filler 7; the second waterproof layer 5 is arranged between the concrete side plate 3 and the thermal insulation layer 6. Among them, the second waterproof layer 5 helps to prevent the erosion of the roadbed material by groundwater, protects the completion of the chemical reaction of calcium carbonate and expansive soil, improves the water permeability resistance of the roadbed, and ensures the long-term stability of the soil; the setting of the thermal insulation layer 6 helps to avoid the adverse effects caused by the drastic temperature difference changes in the goaf throughout the day, helps to ensure that calcium carbonate and expansive soil (first filler 7) can fully react during winter construction (calculated lime and expansive soil mixed reaction will release heat, and the thermal insulation layer 6 can reduce heat loss, thereby helping to achieve the full reaction of calcium carbonate and expansive soil in cold weather), and ensure the strength of the roadbed; in addition, the thermal insulation layer 6 can slow down the temperature difference change, avoid frost heave or thermal expansion and contraction caused by seasonal changes, and in cold areas, it can effectively isolate the external low temperature, avoid frost heave of the roadbed, and reduce cracks and settlement caused by temperature changes.

[0036] In the preferred embodiment of the roadbed structure of the expressway passing through the goaf of the present invention, the second filler 9 is plain soil; the third filler 10 is crushed stone. Among them, the first filler is a mixture of calcium carbonate and expansive soil, which can improve the strength of the first filler and make the roadbed more bearing capacity; the second filler is plain soil, which, as a transition layer, can not only play a role in stabilizing the structure, but also provide a good foundation support for the upper layer of crushed stone or other materials, and provide elastic transition; the third filler is crushed stone, and the crushed stone layer can play the role of a drainage layer; the selection of the above fillers enables the various layers of materials in the roadbed structure to complement each other and work synergistically, thereby improving the overall stability of the roadbed structure.

[0037] Preferably, the crushed stone should be uniform in particle size, with no large difference in particle size, and be able to fill the gap inside the geocell 11 without leaving any pores. More preferably, the particle size of the crushed stone is 10-40 mm.

[0038] In a preferred embodiment of the roadbed structure of a highway passing through a goaf of the present invention, the mixing amount of calcium carbonate in the first filler 7 is 8%, and the expansive soil is the expansive soil on site in the goaf.

[0039] In a preferred embodiment of the roadbed structure of a highway passing through a goaf of the present invention, the first waterproof layer 1 and / or the second waterproof layer 5 can be paved with materials having waterproof properties such as high-density polyethylene (HDPE) waterproof membrane or polyvinyl chloride (PVC) waterproof membrane; the thermal insulation layer 6 can be paved with materials having thermal insulation properties such as expanded perlite, XPS (extruded polystyrene foam board), etc.

[0040] In a preferred embodiment of the roadbed structure of the highway passing through the goaf of the present invention, the thickness of the concrete bottom plate 2 and / or the concrete side plate 3 is 30 cm; the thickness of the partition 4 is 20 cm; the partition 4 is sealed and connected to the concrete bottom plate 3 (preferably, the sealed connection between the partition 4 and the concrete bottom plate 3 is achieved by chemical sealant or sealing strip). The concrete side plate 3 and the partition 4 need to have sufficient rigidity to support the first filler layer (mixture of calcium carbonate and expansive soil) and other upper materials to prevent lateral displacement.

[0041] Preferably, the height of the concrete side panels 3 and / or partitions 4 is 0.6 m; selecting concrete side panels 3 and / or partitions 4 of this height helps to ensure the stability of the structure while not being too high, thereby avoiding material waste.

[0042] Preferably, the height of the geocell 11 is 10-30 cm to effectively enhance the bearing capacity and stability of the roadbed.

[0043] The present invention also proposes a construction method for a roadbed structure of a highway passing through a goaf as described above, comprising the following steps: (1) preparation before construction; (2) laying a first waterproof layer 1; (3) pouring a concrete base plate 2; (4) installing a concrete side plate 3; (5) installing a partition plate 4 in the area enclosed by the concrete base plate 2 and the concrete side plate 3; (6) filling a first filler 7 into the area enclosed by the concrete base plate 2 and the concrete side plate 3; (7) arranging a beam 8 above the concrete side plate 3 and / or the partition plate 4, and filling a second filler 9 around and above the beam 8; (8) arranging a geocell 11 above the second filler 9 inside the area enclosed by the concrete side plate 3 and the concrete base plate 2, and filling the geocell 11 with a third filler 10; and (9) arranging a stabilized soil layer 12 in sequence above the geocell 11.

[0044] Preferably, step (1) includes: after determining the location to be constructed, cleaning the area around the surface of the goaf to prevent debris from appearing at the paving location and thus affecting the stability of the entire roadbed, ensuring that the construction site is clean and tidy; transporting the geocell 11 and materials such as gravel to the construction site to complete the pre-construction preparations.

[0045] Preferably, when laying the first waterproof layer 1 in step (2), the first waterproof layer 1 should ensure full coverage, and the joints should be sealed by heat welding to ensure that there is no water seepage path.

[0046] In a preferred embodiment of the construction method of the roadbed structure of a highway passing through a goaf of the present invention, the step of installing a second waterproof layer 5 and / or a thermal insulation layer 6 on the inner side of the concrete side plate 3 is also included.

[0047] In a preferred embodiment of the construction method of the roadbed structure of a highway passing through a goaf of the present invention, after the concrete base plate 2 is cast, vibration, smoothing and curing are carried out (the concrete base plate 2 is cast on the basis of the first waterproof layer 1, and vibration, smoothing and curing are required after the concrete casting is completed to ensure that the concrete base plate 2 is solid and uniform; during the curing period of the concrete base plate 2, appropriate humidity and temperature should be maintained to avoid cracking of the concrete base plate 2; preferably, the thickness of the concrete base plate 2 is 30 cm); when installing the partition 4, the sealing between the partition 4 and the concrete base plate 2 is ensured.

[0048] Preferably, a chemical sealant or a sealing strip is used at the gap between the partition 4 and the concrete bottom plate 2 to fill the gap therebetween and solidify the gap to form a sealing layer to ensure the sealing between the partition 4 and the concrete bottom plate 2 .

[0049] In a preferred embodiment of the construction method of the roadbed structure of a highway passing through a goaf of the present invention, when filling the first filler 7, the calcium carbonate and the expansive soil are mixed evenly, and then shaped by a grader, and after shaping, they are rolled over the entire width by a roller; the first filler 7 is cured for 14 days (beam 8 is installed after the curing is completed).

[0050] In a preferred embodiment of the construction method of the roadbed structure of a highway passing through a goaf of the present invention, the second filler 9 is filled in the area within the corresponding concrete side plate 3 (i.e., the area enclosed by the concrete side plate 3; preferably, the concrete side plate 3 is arranged along the circumference of the concrete bottom plate 2) until it is evenly and flatly filled (preferably, the second filler 9 is filled to a position slightly higher than the top surface of the beam 8 to help ensure the uniformity and flatness of the second filler 9), and then compacted; when setting the geocell 11, the geocell 11 needs to be straightened and smoothed, close to the lower surface, and anchored at the joints with U-shaped nails. After the anchoring is completed, the third filler 10 is backfilled until it is flush with the height of the geocell 11, and then compacted with a roller after manual leveling.

[0051] Preferably, the concrete side plates 3 are arranged along the circumference of the concrete bottom plate 2; the construction area of ​​the highway passing through the goaf of the present invention is larger than the area enclosed by the concrete side plates 3; the second filler 9 (preferably, the second filler can be made of plain soil) is backfilled in the construction area outside the concrete side plates 3 until it is flush with the top surface of the geocell 11.

[0052] In a preferred embodiment of the construction method of the roadbed structure of a highway passing through a goaf of the present invention, a layer of stabilized soil is laid on top of the geocell 11, and compacted after laying to ensure that it is uniform and dense; a road surface layer 13 is laid on the stabilized soil layer 12, and the temperature and humidity need to be controlled during the construction process to ensure the quality of the surface layer 13. After laying, a roller is used to compact the surface layer 13 to ensure that it has good strength and durability.

[0053] In a preferred embodiment of the construction method of the roadbed structure of a highway passing through a goaf of the present invention, the following steps are included:

[0054] (1) Preparation before construction: After the location to be constructed is determined, the surface of the goaf is cleaned to prevent debris from appearing at the paving location and thus affecting the stability of the entire roadbed, ensuring that the construction site is clean and tidy; the geocell 11 and materials such as gravel are transported to the construction site to complete the preparation before construction;

[0055] (2) Laying the first waterproof layer 1: Lay the first waterproof layer 1 (high-density polyethylene waterproof membrane or polyvinyl chloride waterproof membrane can be used) on the cleaned ground. The first waterproof layer 1 should ensure full coverage, and the joints should be heat-welded or otherwise sealed to ensure that there is no water seepage path;

[0056] (3) Casting concrete base plate 2: On the basis of the first waterproof layer 1, cast concrete base plate 2 with a thickness of 30 cm. After the concrete casting is completed, it needs to be vibrated, leveled and cured to ensure that the base plate is solid and uniform. During the curing period, appropriate humidity and temperature should be maintained to avoid cracking on the surface of the concrete base plate 2;

[0057] (4) Installing concrete side panels 3: Install concrete side panels 3 on the upper part of the concrete bottom plate 2, with a thickness of 30 cm (preferably, the height of the concrete side panels 3 is 0.6 m; the gap between the concrete bottom plate 2 and the concrete side panels 3 is filled with grouting materials to enhance the sealing and bearing capacity between the two; the concrete side panels 3 are arranged along the circumference of the concrete bottom plate 2; more preferably, the concrete side panels 3 are arranged along the circumference of the concrete bottom plate 2);

[0058] (5) Installing a partition 4 between the concrete bottom plate 2 and the concrete side plate 3: Install an internal partition 4 between the concrete side plate 3 and the concrete bottom plate 2. The thickness of the partition 4 is 20 cm. When installing the partition 4, ensure that it is sealed with the concrete bottom plate 2 to avoid the formation of a moisture penetration channel (the gap between the partition 4 and the concrete bottom plate 2 is filled and cured with a chemical sealant or a sealing strip to form a sealing layer). First, set a second waterproof layer 5 (a high-density polyethylene waterproof membrane or a polyvinyl chloride waterproof membrane can be used) on the inner side of the partition 4 and close to the concrete side plate 3 to enhance the waterproof performance of the roadbed and prevent moisture from entering; in addition, set a thermal insulation layer 6 on the inner side of the second waterproof layer 5 (that is, the second waterproof layer 5 is set between the concrete side plate 3 and the thermal insulation layer 6). The thermal insulation layer 6 and the second waterproof layer 5 should be set at the same height as the concrete side plate 3 and the internal partition 4. During the paving process, it is necessary to ensure that the material joints are tight and there are no leaks. The thickness of the thermal insulation layer 6 should meet the design requirements;

[0059] (6) Fill the first filler 7 between the concrete bottom plate 2 and the concrete side plate 3: In the space inside the partition 4, the calcium carbonate and the expansive soil are fully mixed according to the designed ratio (for example, the calcium carbonate content is 8%) to ensure that the reaction is fully carried out; after the mixture is evenly mixed, it is immediately shaped with a grader (the flatness of the roadbed is ensured by shaping with a grader; during the shaping process, the blade of the grader is ensured to be parallel to the ground to avoid unnecessary ups and downs; the roadbed surface is properly trimmed by adjusting the depth of the blade of the grader). The two sides of the road surface should be rolled 2-3 times more. After shaping, it is rolled with a light roller within the full width (before rolling, the first filler 7 should be checked for uniformity to avoid looseness or unevenness). situation; choose a suitable roller, compact in layers, the layer thickness is generally controlled within 100mm to 150mm, and each layer is rolled at least 3-5 times; adopt a combination of static rolling and vibration rolling, vibration rolling can effectively improve the density of the roadbed, and static rolling helps to enhance the overall stability); maintain after rolling, the maintenance time is 14 days (during maintenance, the temperature should be maintained between 10℃ and 30℃, and the humidity range should generally be maintained between 80% and 95%; during maintenance, avoid direct sunlight to prevent rapid evaporation of moisture; if conditions on the construction site permit, use coverings (such as wet sacks or plastic film) to protect the surface and prevent moisture evaporation).

[0060] (7) A beam 8 is arranged above the concrete side plate 3 and the partition plate 4, and the beam 8 is perpendicular to the concrete side plate 3 and the partition plate 4 (the beam 8 and the concrete side plate 3 and the partition plate 4 can be connected by steel bar binding), and a second filler 9 is filled around and above the beam 8 (the second filler 9 can be plain soil; the second filler 9 is filled to a position higher than the top surface of the beam 8, so that the second filler 8 is uniform and flat, and compacted to ensure the stability of the second filler; preferably, the height of the beam is 30 cm, and the thickness of the plain soil above the beam 8 can be 10 cm); wherein, before rolling, the uniformity of the second filler 9 should be checked to avoid looseness or unevenness; a suitable roller is selected, and the layer is compacted in layers, and the layer thickness is generally controlled within 100 mm to 150 mm, and each layer is rolled at least 3-5 times; a method combining static rolling and vibration rolling is adopted, and vibration rolling can effectively improve the density of the roadbed, while static rolling helps to enhance the overall stability.

[0061] (8) A geocell 11 is arranged above the second filler 9 in the area enclosed by the corresponding concrete side plate 3 and the concrete bottom plate 2 (preferably, the height of the geocell 11 is 10-30 cm), and the third filler 10 is filled in the geocell 11: a layer of geocell 11 is laid on the backfill soil (the second filler 9, i.e., plain soil). The geocell 11 needs to be straightened and smooth, close to the lower surface, and no distortion or wrinkles should occur. U-shaped nails are used for anchoring at the joints. After anchoring, crushed stone (with a particle size of 10-40 mm) is used for backfilling until it is flush with the height of the geocell 11. After manual leveling, it is compacted by a roller. In addition, in the construction area outside the concrete side plate 3, the second filler 9 (plain soil) is used for backfilling until it is flush with the top surface of the geocell 11.

[0062] (9) Laying a stabilized soil layer 12 on top of the geocell 11: Lay a layer of stabilized soil (lime stabilized soil; the height of the stabilized soil layer 12 can be 50 cm) on the geocell 11, and compact it after laying to ensure that it is uniform and dense, thereby completing the construction of the roadbed structure of the highway passing through the goaf of this embodiment.

[0063] Then, the road surface layer 13 is laid on the stabilized soil layer 12 (preferably, asphalt concrete can be used as the surface layer material; the height of the surface layer can be 20 cm). The temperature and humidity need to be controlled during the construction process to ensure the quality of the surface layer 13. After paving, the surface layer 13 is compacted by a roller to ensure that it has good strength and durability.

[0064] After paving is completed, check the construction quality of all layers to ensure that the connections between the layers are firm and the surface is flat to meet the requirements. For the parts that need maintenance, such as the concrete base plate 2 and the surface layer 13, they should be maintained in accordance with the specifications to ensure their strength and stability.

[0065] The present invention uses a mixed filler of calcium carbonate and expansive soil between the concrete bottom plate 2, the partition plate 4 and the concrete side plate 3. Compared with traditional fillers, it can significantly improve the engineering properties of the soil and enhance the bearing capacity and stability of the roadbed; the overall support structure formed by the beam and the concrete bottom plate, the concrete side plate and the partition plate system can disperse the load, reduce local pressure concentration, and reduce the risk of uneven settlement; the application of geocells in the roadbed helps to disperse and transfer the upper load, prevent local settlement and road cracking. The design of the first waterproof layer, the second waterproof layer and the thermal insulation layer can not only effectively prevent groundwater infiltration, but also reduce the impact of temperature changes on the roadbed material, thereby extending the service life of the roadbed.

[0066] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A roadbed structure for a highway passing through a goaf, characterized in that: It includes a first waterproof layer, a roadbed and a stabilized soil layer arranged in sequence from bottom to top; The roadbed includes a concrete base plate, concrete side plates, partitions, beams and geocells; the concrete side plates are arranged on the sides of the concrete base plate; the partitions are arranged in the area surrounded by the concrete base plate and the concrete side plates, and a first filler is arranged between the partitions or between the partitions and the concrete side plates, and the first filler is a mixture of calcium carbonate and expansive soil; the beams are arranged above the partitions and / or the concrete side plates, and a second filler is arranged around and above the beams; the geocell is arranged above the second filler in the area surrounded by the corresponding concrete side plates and the concrete base plate, and a third filler is arranged in the geocell.

2. The roadbed structure of a highway passing through a goaf as claimed in claim 1, characterized in that: A second waterproof layer and / or a thermal insulation layer is provided between the concrete side plate and the first filler; The second waterproof layer is arranged between the concrete side plate and the thermal insulation layer.

3. The roadbed structure of a highway passing through a goaf as claimed in claim 1, characterized in that: The second filler is plain soil; The third filler is crushed stone.

4. The roadbed structure of a highway passing through a goaf as claimed in claim 1, characterized in that: The thickness of the concrete bottom plate and / or concrete side plate is 30 cm; the thickness of the partition plate is 20 cm; The partition is sealed and connected to the concrete bottom plate.

5. The method for constructing a roadbed structure of a highway passing through a goaf as claimed in any one of claims 1 to 4, characterized in that: The steps include: (1) Preparation before construction; (2) laying the first waterproof layer; (3) pouring the concrete base plate; (4) installing the concrete side panels; (5) installing the partition in the area enclosed by the concrete bottom plate and the concrete side plates; (6) filling the first filler into the area enclosed by the concrete bottom plate and the concrete side plates; (7) Arranging a beam above the concrete side plate and / or partition, and filling a second filler around and above the beam; (8) a geocell is provided above the second filler in the area enclosed by the corresponding concrete side plate and the concrete bottom plate, and a third filler is filled in the geocell; (9) Laying a stable soil layer above the geocell.

6. The method for constructing a roadbed structure of a highway passing through a goaf as claimed in claim 5, characterized in that: The method also includes the step of installing a second waterproof layer and / or a thermal insulation layer on the inner side of the concrete side slab.

7. The method for constructing a roadbed structure of a highway passing through a goaf as claimed in claim 5, characterized in that: After the concrete base plate is poured, it is vibrated, leveled and cured; When installing the partition, ensure the sealing between the partition and the concrete base plate.

8. The method for constructing a roadbed structure of a highway passing through a goaf as claimed in claim 5, characterized in that: When filling the first filler, firstly, the calcium carbonate and the expanded soil are mixed evenly, and then shaped by a grader, and then rolled by a roller within the full width; After the rolling is completed, the first filler is cured, and the curing time of the first filler is 14 days.

9. The method for constructing a roadbed structure of a highway passing through a goaf as claimed in claim 5, characterized in that: After filling the second filler until it is evenly leveled, compacting is performed; When setting up the geocell, the geocell needs to be straightened and smoothed, close to the lower surface, and anchored with U-shaped nails at the joints. After the anchoring is completed, the third filler is filled.

Images