Hexagonal drainage blind ditch structure at the bottom of the high fill backfill gully in collapsible loess areas

Abstract

This utility model discloses a hexagonal drainage blind ditch structure at the bottom of a high-fill backfill ditch in collapsible loess areas. It includes a rubble layer, an inner crushed stone layer, an inner gravel layer, a waterproof layer, an outer crushed stone layer, and an outer gravel layer. The longitudinal sections of all these layers are hexagonal. The combination of crushed stone, rubble, gravel, and the waterproof layer with different particle sizes ensures that infiltrated water is collected at the center of the hexagonal blind ditch, while preventing backfill soil from entering and being lost. Furthermore, the hexagonal design of this drainage blind ditch increases the contact area for collecting seepage water at the bottom of the high-fill backfill ditch, significantly improving the seepage water content inside the ditch, preventing settlement due to seepage water, and enhancing the stability of the backfill ditch.

Description

Technical Field

[0001] This utility model belongs to the field of drainage blind ditch technology, and in particular relates to a hexagonal drainage blind ditch structure at the bottom of a high-fill backfill ditch in collapsible loess areas. Background Technology

[0002] Many areas have significant topographic relief, with natural gullies crisscrossing the landscape; some areas have elevation differences of 20m-36m. To meet the needs of urban development and construction, these natural gullies require compaction and backfilling to eliminate collapsibility and ensure the foundation requirements for building structures are met. These gullies are ancient, primarily formed by rural sewage and flood drainage in the last century. Later, due to the development of vertical fissures in the loess, the banks of the gullies collapsed under the erosion of rainwater. Effectively managing these natural gullies is a challenge. The traditional mainstream method is compaction and backfilling. However, relying solely on this method can lead to seepage water within the gullies during and after backfilling, causing vertical settlement and displacement in high-fill gullies, which is detrimental to their stability. Utility Model Content

[0003] The technical problem this invention aims to solve is to address the shortcomings of the existing technology by providing a hexagonal drainage blind ditch structure at the bottom of a high-fill backfill ditch in collapsible loess areas. This structure utilizes a combination of crushed stone, rubble, gravel with different particle sizes and a waterproof layer to ensure that infiltrated water is collected at the center of the hexagonal blind ditch, while simultaneously preventing backfill soil from entering and being lost. Furthermore, the hexagonal design of this drainage blind ditch increases the contact area for collecting seepage water at the bottom of the high-fill backfill ditch. The hexagonal drainage blind ditch's longitudinal slope gravity then discharges the collected water outside the high-fill backfill ditch, significantly improving the seepage water content within the ditch, preventing settlement due to seepage, and enhancing the stability of the backfill ditch.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is: a hexagonal drainage blind ditch structure at the bottom of the high fill backfill ditch in collapsible loess areas, including a rubble layer, an inner crushed stone layer, an inner gravel layer, a waterproof layer, an outer crushed stone layer, and an outer gravel layer arranged sequentially from the inside to the outside at the bottom of the backfill ditch. The rubble layer, the inner crushed stone layer, the inner gravel layer, the waterproof layer, the outer crushed stone layer, and the outer gravel layer are all arranged along the extension direction of the backfill ditch, and the longitudinal section of the rubble layer, the inner crushed stone layer, the inner gravel layer, the waterproof layer, the outer crushed stone layer, and the outer gravel layer are all hexagonal structures.

[0005] The inner crushed stone layer covers the outer side of the rubble layer, and the inner side of the inner crushed stone layer is in close contact with the outer side of the rubble layer; the inner gravel layer covers the outer side of the inner crushed stone layer, and the inner side of the inner gravel layer is in close contact with the outer side of the inner crushed stone layer; the waterproof layer covers the outer side of the inner gravel layer, and the inner side of the waterproof layer is in close contact with the outer side of the inner gravel layer; the outer crushed stone layer covers the outer side of the waterproof layer, and the inner side of the outer crushed stone layer is in close contact with the outer side of the waterproof layer; the outer gravel layer covers the outer side of the outer crushed stone layer, and the inner side of the outer gravel layer is in close contact with the outer side of the outer crushed stone layer.

[0006] The upper half of the rubble layer, inner crushed stone layer, inner gravel layer, waterproof layer, outer crushed stone layer, and outer gravel layer are laid on the ground, while the lower half of the rubble layer, inner crushed stone layer, inner gravel layer, waterproof layer, outer crushed stone layer, and outer gravel layer are laid underground.

[0007] Furthermore, the waterproof layer is composed of multiple waterproof geotextiles, which are laid along the extension direction of the backfill ditch. The ends of two adjacent waterproof geotextiles are overlapped, and the overlap length of two adjacent waterproof geotextile ends is not less than 200mm.

[0008] Furthermore, the thickness of the rubble layer ranges from 600mm to 1000mm; the thickness of the inner crushed stone layer ranges from 140mm to 160mm; the thickness of the inner gravel layer ranges from 40mm to 60mm; the thickness of the outer crushed stone layer ranges from 140mm to 160mm; and the thickness of the outer gravel layer ranges from 40mm to 60mm.

[0009] Furthermore, the diameter of the rubble in the rubble layer ranges from 150mm to 300mm; the diameter of the crushed stone in the inner gravel layer ranges from 20mm to 50mm; the diameter of the gravel in the inner gravel layer ranges from 2mm to 20mm; the diameter of the crushed stone in the outer gravel layer ranges from 20mm to 50mm; and the diameter of the gravel in the outer gravel layer ranges from 2mm to 20mm.

[0010] Furthermore, the slope ratio of each inclined side of the rubble layer, the inner crushed stone layer, the inner gravel layer, the waterproof layer, the outer crushed stone layer, and the outer gravel layer is 1:1.

[0011] This utility model has the following advantages compared with the prior art:

[0012] 1. This utility model uses a combination of crushed stone, rubble, gravel with different particle sizes and a waterproof layer to ensure that infiltrated water is collected at the center of the hexagonal blind ditch, while ensuring that the backfill soil in the upper high fill backfill area does not enter the blind ditch and be lost. In addition, the hexagonal structure of this drainage blind ditch increases the contact area for collecting seepage water at the bottom of the high fill backfill ditch. The longitudinal slope gravity of the hexagonal drainage blind ditch discharges the collected water into the outside of the high fill backfill ditch, significantly improving the seepage water content inside the high fill backfill ditch, preventing the ditch from settling due to seepage water, and improving the stability of the backfill ditch.

[0013] 2. This utility model, through the setting of inner and outer gravel layers, can effectively prevent particles from entering the interior of the blind ditch in the upper 20-meter backfill area and being discharged and lost through the voids inside the blind ditch, thereby causing the loss of backfill soil.

[0014] 3. The central stone layer of this utility model blind ditch has a large gap space, which can effectively collect the seepage water collected in the blind ditch and thus effectively discharge it outside the ditch; and the large space of the central stone can effectively connect with the filter bag and drainage pipe at the end of the ditch, increasing the drainage area at the end of the blind ditch and allowing the water collected in the blind ditch to be quickly discharged outside the ditch at the end of the blind ditch.

[0015] In summary, this utility model, through the combination of crushed stone, rubble, gravel with different particle sizes and a waterproof layer, ensures that infiltrated water is collected at the center of the hexagonal blind ditch, while ensuring that the backfill soil in the upper high-fill backfill area does not enter the blind ditch and be lost. In addition, the hexagonal structure of this drainage blind ditch increases the contact area for collecting seepage water at the bottom of the high-fill backfill ditch. The longitudinal slope gravity of the hexagonal drainage blind ditch discharges the collected water outside the high-fill backfill ditch, significantly improving the seepage water content inside the high-fill backfill ditch, preventing the ditch from settling due to seepage water, and improving the stability of the backfill ditch.

[0016] The technical solution of this utility model will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of this utility model.

[0018] Explanation of reference numerals in the attached figures:

[0019] 1—Backfilled gully; 2—Rock layer; 3—Inner layer of crushed stone;

[0020] 4—Inner gravel layer; 5—Waterproof layer; 6—Outer crushed stone layer;

[0021] 7—Outer gravel layer. Detailed Implementation

[0022] like Figure 1 As shown, this utility model includes a rubble layer 2, an inner crushed stone layer 3, an inner gravel layer 4, a waterproof layer 5, an outer crushed stone layer 6, and an outer gravel layer 7 arranged sequentially from the inside to the outside at the bottom of the backfill ditch 1. The rubble layer 2, the inner crushed stone layer 3, the inner gravel layer 4, the waterproof layer 5, the outer crushed stone layer 6, and the outer gravel layer 7 are all arranged along the extension direction of the backfill ditch 1, and the longitudinal section of the rubble layer 2, the inner crushed stone layer 3, the inner gravel layer 4, the waterproof layer 5, the outer crushed stone layer 6, and the outer gravel layer 7 is a hexagonal structure.

[0023] The inner crushed stone layer 3 covers the outer side of the rubble layer 2, and the inner side of the inner crushed stone layer 3 is in close contact with the outer side of the rubble layer 2; the inner gravel layer 4 covers the outer side of the inner crushed stone layer 3, and the inner side of the inner gravel layer 4 is in close contact with the outer side of the inner crushed stone layer 3; the waterproof layer 5 covers the outer side of the inner gravel layer 4, and the inner side of the waterproof layer 5 is in close contact with the outer side of the inner gravel layer 4; the outer crushed stone layer 6 covers the outer side of the waterproof layer 5, and the inner side of the outer crushed stone layer 6 is in close contact with the outer side of the waterproof layer 5; the outer gravel layer 7 covers the outer side of the outer crushed stone layer 6, and the inner side of the outer gravel layer 7 is in close contact with the outer side of the outer crushed stone layer 6.

[0024] The upper half of the rubble layer 2, inner crushed stone layer 3, inner gravel layer 4, waterproof layer 5, outer crushed stone layer 6, and outer gravel layer 7 are laid on the ground, while the lower half of the rubble layer 2, inner crushed stone layer 3, inner gravel layer 4, waterproof layer 5, outer crushed stone layer 6, and outer gravel layer 7 are laid underground.

[0025] In practical use, the combination of crushed stone, rubble, gravel with different particle sizes and a waterproof layer ensures that infiltrated water is collected at the center of the hexagonal blind ditch, while ensuring that the backfill soil in the upper high-fill backfill area does not enter the blind ditch and be lost. In addition, the hexagonal structure of this drainage blind ditch increases the contact area for collecting seepage water at the bottom of the high-fill backfill ditch. The longitudinal slope gravity of the hexagonal drainage blind ditch discharges the collected water outside the high-fill backfill ditch, significantly improving the seepage water content inside the high-fill backfill ditch, preventing the ditch from settling due to seepage water, and improving the stability of the backfill ditch.

[0026] The inner gravel layer 4 and the outer gravel layer 7 can effectively prevent particles from entering the blind ditch from the upper 20-meter backfill area and being discharged through the voids inside the blind ditch, thus preventing the loss of backfill soil.

[0027] In addition, the central stone layer 2 of the blind drain has a large void space, which can effectively collect the seepage water collected in the blind drain and thus effectively discharge it outside the gully blind drain; and the large space of the central stone can effectively connect with the filter bag and drainage pipe at the end of the gully blind drain, increasing the drainage area at the end of the blind drain and allowing the water collected in the blind drain to be quickly discharged outside the gully at the end of the blind drain.

[0028] It should be noted that the original foundation needs to be compacted or dynamically tamped before construction of this drainage blind ditch structure to ensure that the blind ditch itself will not settle and break, thereby ensuring the overall settlement stability of the high-fill backfill gully. At the end of the gully head, a drainage pipe is laid from the blind ditch to drain outside the gully head. The hexagonal drainage blind ditch at the bottom of the high-fill backfill gully can be appropriately adjusted according to the actual terrain, geology, and other conditions. The longitudinal slope of the blind ditch should not be less than 1%, and a drainage pipe is laid from the blind ditch to drain outside the gully head.

[0029] In particular, compared with traditional trapezoidal or rectangular blind drains, this drainage blind drain structure increases the number and length of its sides, expanding the siphon effect of the blind drain on seepage water; it also increases the contact area for collecting seepage water in the blind drain at the bottom of the high-fill backfill gully, thus more effectively absorbing seepage water within the cross-sectional length of the gully, effectively collecting and draining seepage water from the high-fill gully backfill area in collapsible loess areas, ensuring that the settlement of the backfill area is not significantly affected by seepage water.

[0030] In this embodiment, the waterproof layer 5 is composed of multiple waterproof geotextiles, which are laid along the extension direction of the backfill ditch 1. The ends of two adjacent waterproof geotextiles are overlapped, and the overlap length of the ends of two adjacent waterproof geotextiles is not less than 200mm.

[0031] In actual use, the preferred overlap length between the ends of two adjacent waterproof geotextiles is 200mm, and the waterproof geotextiles must meet the required density of 400g / ㎡.

[0032] In this embodiment, the thickness of the rubble layer 2 ranges from 600mm to 1000mm; the thickness of the inner crushed stone layer 3 ranges from 140mm to 160mm; the thickness of the inner gravel layer 4 ranges from 40mm to 60mm; the thickness of the outer crushed stone layer 6 ranges from 140mm to 160mm; and the thickness of the outer gravel layer 7 ranges from 40mm to 60mm.

[0033] In actual use, the thickness of the rubble layer 2 is preferably 800 mm; the thickness of the inner crushed stone layer 3 is preferably 150 mm; the thickness of the inner gravel layer 4 is preferably 50 mm; the thickness of the outer crushed stone layer 6 is preferably 150 mm; and the thickness of the outer gravel layer 7 is preferably 50 mm.

[0034] In this embodiment, the following features are provided: the diameter of the rubble in the rubble layer 2 ranges from 150mm to 300mm; the diameter of the crushed stone in the inner crushed stone layer 3 ranges from 20mm to 50mm; the diameter of the gravel in the inner gravel layer 4 ranges from 2mm to 20mm; the diameter of the crushed stone in the outer crushed stone layer 6 ranges from 20mm to 50mm; and the diameter of the gravel in the outer gravel layer 7 ranges from 2mm to 20mm.

[0035] In this embodiment, the slope ratio of each inclined side of the rubble layer 2, the inner crushed stone layer 3, the inner gravel layer 4, the waterproof layer 5, the outer crushed stone layer 6, and the outer gravel layer 7 is 1:1.

[0036] When using this utility model, an excavator is required to thoroughly remove all turf, tree roots, and plant soil within the ditch area as required. The bottom of the blind ditch is then filled with rubble and gravel, and wrapped with non-woven geotextile around the perimeter. During the filling process, the terrain elevation must be measured regularly, and the ditch slope must be no less than 1%. The bottom and walls of the ditch are then manually trimmed and compacted to prevent puncturing the geotextile. When using geotextile as a filter layer, it should first be laid on the bottom and side walls, leaving space for the top to cover the required geotextile. It should be stretched straight and tightly adhered to the underlying layer. All longitudinal and transverse overlaps should be staggered, with an overlap length of no less than 200mm. After the geotextile is laid, a loader is used to fill the bottom layer with large-diameter rubble as a filter layer, followed by the middle layer with small-diameter gravel, and then manually leveled. After the upper gravel layer is completed, the geotextile is rolled up and closed.

[0037] The above description is merely a preferred embodiment of the present utility model and does not constitute any limitation on the present utility model. Any simple modifications, alterations, or equivalent structural changes made to the above embodiments based on the technical essence of the present utility model shall still fall within the protection scope of the present utility model.

Claims

1. A hexagonal drainage blind ditch structure at the bottom of a backfill gully in a collapsible loess area with high fill, characterized in that: The backfill ditch (1) includes a rubble layer (2), an inner crushed stone layer (3), an inner gravel layer (4), a waterproof layer (5), an outer crushed stone layer (6), and an outer gravel layer (7) arranged sequentially from the inside to the outside. The rubble layer (2), the inner crushed stone layer (3), the inner gravel layer (4), the waterproof layer (5), the outer crushed stone layer (6), and the outer gravel layer (7) are all arranged along the extension direction of the backfill ditch (1), and the longitudinal section of the rubble layer (2), the inner crushed stone layer (3), the inner gravel layer (4), the waterproof layer (5), the outer crushed stone layer (6), and the outer gravel layer (7) is a hexagonal structure. The inner crushed stone layer (3) covers the outer side of the rubble layer (2), and the inner side of the inner crushed stone layer (3) is in close contact with the outer side of the rubble layer (2); the inner gravel layer (4) covers the outer side of the inner crushed stone layer (3), and the inner side of the inner gravel layer (4) is in close contact with the outer side of the inner crushed stone layer (3); the waterproof layer (5) covers the outer side of the inner gravel layer (4), and the inner side of the waterproof layer (5) is in close contact with the outer side of the inner gravel layer (4); the outer crushed stone layer (6) covers the outer side of the waterproof layer (5), and the inner side of the outer crushed stone layer (6) is in close contact with the outer side of the waterproof layer (5); the outer gravel layer (7) covers the outer side of the outer crushed stone layer (6), and the inner side of the outer gravel layer (7) is in close contact with the outer side of the outer crushed stone layer (6). The upper half of the rubble layer (2), inner crushed stone layer (3), inner gravel layer (4), waterproof layer (5), outer crushed stone layer (6), and outer gravel layer (7) are laid on the ground, while the lower half of the rubble layer (2), inner crushed stone layer (3), inner gravel layer (4), waterproof layer (5), outer crushed stone layer (6), and outer gravel layer (7) are laid underground.

2. The hexagonal drainage blind ditch structure at the bottom of the high-fill backfill gully in collapsible loess areas according to claim 1, characterized in that: The waterproof layer (5) is composed of multiple waterproof geotextiles, which are laid along the extension direction of the backfill ditch (1). The ends of two adjacent waterproof geotextiles are overlapped, and the overlap length of the ends of two adjacent waterproof geotextiles is not less than 200mm.

3. The hexagonal drainage blind ditch structure at the bottom of the high-fill backfill gully in collapsible loess areas according to claim 1, characterized in that: The thickness of the rubble layer (2) ranges from 600mm to 1000mm; the thickness of the inner crushed stone layer (3) ranges from 140mm to 160mm; the thickness of the inner gravel layer (4) ranges from 40mm to 60mm; the thickness of the outer crushed stone layer (6) ranges from 140mm to 160mm; and the thickness of the outer gravel layer (7) ranges from 40mm to 60mm.

4. The hexagonal drainage blind ditch structure at the bottom of the high-fill backfill gully in collapsible loess areas according to claim 1, characterized in that: The diameter of the rubble in the rubble layer (2) ranges from 150mm to 300mm; the diameter of the crushed stone in the inner gravel layer (3) ranges from 20mm to 50mm; the diameter of the gravel in the inner gravel layer (4) ranges from 2mm to 20mm; the diameter of the crushed stone in the outer gravel layer (6) ranges from 20mm to 50mm; and the diameter of the gravel in the outer gravel layer (7) ranges from 2mm to 20mm.

5. The hexagonal drainage blind ditch structure at the bottom of the high-fill backfill gully in collapsible loess areas according to claim 1, characterized in that: The slope ratio of each inclined side of the rubble layer (2), inner crushed stone layer (3), inner gravel layer (4), waterproof layer (5), outer crushed stone layer (6), and outer gravel layer (7) is 1:1.

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