A construction structure for a slanting well of a landfill rock steep slope

Abstract

The utility model discloses a construction structure for the inclined well of the rock abrupt slope of landfill, including flexible reinforced retaining wall base groove, flexible reinforced retaining wall base groove sets up on the reinforced retaining wall along the rock abrupt slope of original state and is built, and the longitudinal section of flexible reinforced retaining wall base groove is inverted trapezoid, and the inclined well is equipped in flexible reinforced retaining wall base groove, and the inclined well is three -section type structure, and from top to bottom includes vertical solid wall pipe, horizontal solid wall pipe and horizontal perforated pipe fixedly connected through flange in proper order, and the pit mouth position of inclined well is positioned through fixed pier, and deep well pump and the exhaust pipe communicated with deep well pump are installed in inclined well, and flexible reinforced retaining wall base groove is layered backfilling according to the installation progress of inclined well. The construction structure can realize the installation and fixed of the inclined well of the rock abrupt slope of original state and is built and can make the construction accident rate obviously reduce, especially in two -stage slope scene, can completely eliminate the personnel casualty and equipment damage caused by pipeline rolling.

Description

Technical Field

[0001] This utility model relates to the field of slope construction technology, specifically to a construction structure for a sloping well on a steep rock slope in a landfill. Background Technology

[0002] Inclined wells in landfills are common pumping wells used for groundwater and leachate drainage in landfills. They are easy to construct and have a short pumping path. They can also reduce the construction investment of external lifting wells and the support costs of deep foundation pits, thus saving investment to a large extent. They are also beneficial to construction safety and later operation and maintenance. Therefore, they are widely used in landfills.

[0003] When constructing inclined wells, a foundation trench needs to be reserved during the construction phase of the reservoir slope to facilitate the fixing and installation of vertical HDPE pipes. In landfills with conventional soil slopes, the foundation trench can be excavated and formed in one go during slope trimming, and the vertical pipes can be welded off-site and then lowered into the foundation trench as a whole.

[0004] However, for landfills with undisturbed rock slopes that meet the conditions of exceeding 10m in height, having a slope of ≤1:1, and lacking a working surface, it is impossible to construct foundation trenches for inclined wells for groundwater and leachate. If vertical pipes are placed directly on the slope, not only is effective fixation difficult, but there is also a significant risk of tilting to either side or even rolling off the slope. Assuming the landfill has a two-tiered slope, and considering a 20m long vertical pipe, its weight would be approximately 1.1 to 1.8 tons; the consequences of a rollover would be unimaginable. Therefore, the installation of inclined wells in such landfills faces extremely significant challenges. Utility Model Content

[0005] To address the shortcomings of existing technologies, this utility model provides a construction structure for inclined wells on steep rock slopes of landfills. This construction structure enables the installation and fixation of inclined wells in landfills composed of undisturbed rock slopes, significantly reducing the construction accident rate. Especially in two-level slope scenarios, it can completely eliminate personnel injuries and equipment damage caused by pipe roll-off.

[0006] A construction structure for a sloping well on a steep rock slope in a landfill includes a flexible reinforced retaining wall trench. The trench is installed on a reinforced retaining wall constructed along the original rock slope. The longitudinal section of the trench is an inverted trapezoid. A sloping well is installed within the trench. The well has a three-section structure, consisting of a vertical solid-wall pipe, a horizontal solid-wall pipe, and a horizontal perforated pipe, all fixedly connected by flanges from top to bottom. The wellhead is positioned using fixed supports. A deep well pump and a pumping pipe connected to the pump are installed within the well. The trench is backfilled in layers according to the installation progress of the sloping well.

[0007] As a preferred embodiment of the above technical solution, the reinforced retaining wall adopts a two-stage flexible reinforced retaining wall, and the foundation trench of the flexible reinforced retaining wall is set on the slope of the first stage of the flexible reinforced retaining wall.

[0008] As a preferred embodiment of the above technical solution, the height of the flexible reinforced retaining wall foundation trench is 3-5m, with a 1:1 slope on both sides, and symmetrical steps are set on both sides every 1m-1.5m.

[0009] As a preferred embodiment of the above technical solution, the inclined well includes a groundwater inclined well, a secondary leachate drainage inclined well, and a primary leachate drainage inclined well arranged in parallel.

[0010] As a preferred embodiment of the above technical solution, the vertical solid-wall pipe, the horizontal solid-wall pipe, and the horizontal perforated pipe are all made of HDPE pipe.

[0011] As a preferred option for the above technical solution, the selected HDPE pipe material is PE100, with a nominal pressure of not less than 1.0MPa.

[0012] As a preferred embodiment of the above technical solution, the flange is composed of a 304 stainless steel flange plate, an HDPE flange head, a rubber gasket, and bolts.

[0013] As a preferred embodiment of the above technical solution, the fixed pier is made of C20 plain concrete.

[0014] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0015] 1. Overcome the limitations of construction on steep rock slopes and solve installation problems.

[0016] Traditional methods often fail to secure pipelines on steep rock slopes due to the inability to excavate foundation trenches, leading to unstable pipeline anchorage and a tendency to overturn. This method addresses this by creating an inverted trapezoidal foundation trench (1:1 slope on both sides, with symmetrical steps every 1-1.5m) within a first-level reinforced soil retaining wall, providing initial anchorage space for the pipeline. Backfilling the trench utilizes a layered, compacted clay and reinforcing material combination, along with a bagged soil backfilling process, creating a rigid constraint between the pipeline and the slope. This completely solves the problem of "no working surface for anchorage" and meets safe construction requirements.

[0017] 2. Improve construction safety and avoid major risks.

[0018] To address the risks associated with working at heights using long HDPE pipes (e.g., a DN800 pipe, 20m long, weighing up to 1.8 tons), this method employs a "segmented extension + alternating construction" strategy: each 6m segment of pipe is connected via flanges for modular installation, avoiding the risk of falling during overall hoisting. Simultaneously, during the synchronous raising of the reinforced soil retaining wall and the pipe, the clamping force between the retaining wall soil and the rock slope forms a "dynamic stability system"—the pipe is immediately extended when it protrudes less than 0.5m from the top of the retaining wall, ensuring the pipe remains under constraint at all times. This method significantly reduces the accident rate, especially in scenarios with two-level slopes, completely eliminating personnel injuries and equipment damage caused by pipe roll-off. Attached Figure Description

[0019] Figure 1 This is a top view of the foundation trench for the flexible reinforced soil retaining wall of this utility model.

[0020] Figure 2 This is a cross-sectional view of the inclined well for groundwater drainage according to this utility model.

[0021] Figure 3 This is a cross-sectional view of the primary and secondary drainage inclined wells of the present invention.

[0022] The attached diagram is labeled as follows: 1-Flexible reinforced retaining wall foundation trench, 2-Original rock slope, 3-Reinforced retaining wall, 4-Flange, 5-Vertical solid wall pipe, 6-Horizontal solid wall pipe, 7-Horizontal perforated pipe, 8-Fixed pier, 9-Deep well pump, 10-Drainage pipe, 11-Groundwater inclined well, 12-Secondary leachate drainage inclined well, 13-Primary leachate drainage inclined well. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model 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 utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0024] The present invention will now be described in further detail with reference to the accompanying drawings:

[0025] like Figures 1 to 3The diagram illustrates a construction structure for a sloping well on a steep rock slope in a landfill. It includes a flexible reinforced retaining wall trench 1, which is installed on a reinforced retaining wall 3 constructed along the original rock slope 2. The longitudinal section of the flexible reinforced retaining wall trench 1 is an inverted trapezoid. A sloping well is located within the flexible reinforced retaining wall trench 1. The sloping well has a three-section structure, consisting of a vertical solid-wall pipe 6, a horizontal solid-wall pipe 7, and a horizontal perforated pipe 8, all fixedly connected by flanges 5 from top to bottom. The opening of the sloping well is positioned using fixed piers 8. A deep well pump 9 and a drainage pipe 10 connected to the deep well pump 9 are installed within the sloping well. The flexible reinforced retaining wall trench 1 is backfilled in layers according to the installation progress of the sloping well.

[0026] In this embodiment, the reinforced retaining wall 3 adopts a two-stage flexible reinforced retaining wall, and the foundation trench 1 of the flexible reinforced retaining wall is set on the slope of the first-stage flexible reinforced retaining wall.

[0027] In this embodiment, the height of the flexible reinforced retaining wall foundation trench 1 is 3 to 5 m, with a 1:1 slope on both sides, and symmetrical steps are set on both sides every 1 m to 1.5 m.

[0028] In this embodiment, the inclined well includes a groundwater inclined well 11, a secondary leachate drainage inclined well 12, and a primary leachate drainage inclined well 13 arranged in parallel.

[0029] In this embodiment, the vertical solid wall pipe 5, the horizontal solid wall pipe 6, and the horizontal perforated pipe 7 are all made of HDPE pipe.

[0030] In this embodiment, the selected HDPE pipe is of PE100 grade and has a nominal pressure of not less than 1.0MPa.

[0031] In this embodiment, the flange 4 is composed of a stainless steel 304 flange plate, an HDPE flange head, a rubber gasket, and bolts.

[0032] In this embodiment, the fixed pier 8 is made of C20 plain concrete.

[0033] This fly ash landfill is a valley-type landfill. The original slope 1 is composed of moderately weathered hard sandstone with an average height of 15m and a slope of 1:1. In order to obtain a smooth base surface and anchoring platform to facilitate the laying of the impermeable layer, a reinforced soil retaining wall 3 needs to be set on the inner side of the slope. This reinforced soil retaining wall 3 is a two-stage flexible reinforced soil retaining wall. The first stage is 8m high and 8m wide, and the second stage is 7m high and 4m wide.

[0034] The installation sequence of the inclined shafts in this landfill project is as follows:

[0035] 1. Construction of the foundation trench 1 for the flexible reinforced soil retaining wall: To facilitate the installation and fixing of the inclined wells, an inverted trapezoidal foundation trench needs to be reserved at the construction location of the inclined wells in the first-level reinforced soil retaining wall 3. The width of the foundation trench is determined according to the HDPE pipe diameter and the number of inclined wells. In this project, the diameter of the HDPE pipes for the inclined wells is 500mm, the distance between two wells is 1m, and the distance from the outermost well to the slope of the foundation trench is 0.75m. Therefore, the width of the foundation trench is 4m. In addition, the height of the foundation trench is 4m, with a 1:1 slope on both sides, and symmetrical steps are set every 1m on both sides. The platform width is 0.5m.

[0036] 2. Installation of the first vertical inclined well: After the pipeline foundation is prepared, the horizontal solid wall pipe 6 and the horizontal perforated pipe 7 are welded in advance, and the first vertical solid wall pipe 5 and the horizontal solid wall pipe 6 are welded together using elbows. The finished pipeline is placed in the flexible reinforced soil retaining wall trench 1 and fixed to ensure that the back of the pipeline is close to the steep rock slope.

[0037] 3. Foundation trench backfilling: The flexible reinforced soil retaining wall foundation trench 1 is backfilled with clay in layers and compacted. High-toughness polyester woven geotextile is laid. Bags of soil are stacked on the slope and wrapped and fixed with high-toughness polyester woven geotextile. Repeat the above steps until the foundation trench backfilling work is completed.

[0038] 4. Vertical Second Section Inclined Well Extension: The head of the first section of vertical solid wall pipe 5 is pre-welded to the HDPE flange. Then, the flange and gasket are installed, and the bolts are tightened to extend the first section of vertical solid wall pipe 5. The length of each vertical extension HDPE pipe is 6m.

[0039] 5. Alternating construction of flexible reinforced soil retaining wall 3 and inclined well vertical section: The reinforced soil retaining wall 3 is continuously heightened, and the inclined well is fixed between the reinforced soil retaining wall 1 and the steep rock slope. When the vertical solid wall pipe 5 protrudes less than 0.5m from the top of the retaining wall, the next section of the vertical solid wall pipe 5 is extended using a flange. Then the construction of the flexible reinforced soil retaining wall 3 continues. The above steps are repeated until the construction of the retaining wall and the inclined well is completed.

[0040] In this embodiment, an inverted trapezoidal foundation trench is set in the first-level reinforced soil retaining wall to provide initial anchoring space for the pipeline. During the backfilling of the foundation trench, the clamping force between the retaining wall soil and the rock slope is used to form a "dynamically stable system". At the same time, this method adopts the strategy of "segmented height increase + alternating construction" to ensure that the pipeline is always in a constrained state, avoid the risk of falling during overall hoisting, and eliminate personnel casualties and equipment damage caused by pipeline rolling, thus providing a guarantee for the efficient and stable completion of the installation of the inclined shaft.

[0041] The above are merely preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A construction structure for a sloping well on a steep rock slope in a landfill, characterized in that: The system includes a flexible reinforced retaining wall foundation trench, which is installed on a reinforced retaining wall constructed along the original rock slope. The longitudinal section of the flexible reinforced retaining wall foundation trench is an inverted trapezoid. An inclined well is provided inside the flexible reinforced retaining wall foundation trench. The inclined well has a three-section structure, consisting of a vertical solid-wall pipe, a horizontal solid-wall pipe, and a horizontal perforated pipe, which are fixedly connected by flanges from top to bottom. The pit opening of the inclined well is positioned by a fixed pier. A deep well pump and a pumping pipe connected to the deep well pump are installed inside the inclined well. The flexible reinforced retaining wall foundation trench is backfilled in layers according to the installation progress of the inclined well.

2. The construction structure for a sloping well on a steep rock slope in a landfill as described in claim 1, characterized in that: The reinforced retaining wall adopts a two-stage flexible reinforced retaining wall, and the foundation trench of the flexible reinforced retaining wall is set on the slope of the first stage of the flexible reinforced retaining wall.

3. The construction structure for a sloping well on a steep rock slope in a landfill as described in claim 1, characterized in that: The height of the foundation trench for the flexible reinforced retaining wall is 3 to 5 meters, with a 1:1 slope on both sides and symmetrical steps every 1 to 1.5 meters on both sides.

4. The construction structure for a sloping well on a steep rock slope in a landfill as described in claim 1, characterized in that: The inclined wells include parallel inclined wells for groundwater drainage, secondary inclined wells for leachate drainage, and primary inclined wells for leachate drainage.

5. The construction structure for a sloping well on a steep rock slope in a landfill as described in claim 1, characterized in that: The vertical solid-wall pipe, horizontal solid-wall pipe, and horizontal perforated pipe are all made of HDPE pipe.

6. The construction structure for a sloping well on a steep rock slope in a landfill as described in claim 5, characterized in that: The selected HDPE pipe is of PE100 grade and has a nominal pressure of not less than 1.0MPa.

7. The construction structure for a sloping well on a steep rock slope in a landfill as described in claim 1, characterized in that: The flange consists of a 304 stainless steel flange plate, an HDPE flange head, a rubber gasket, and bolts.

8. The construction structure for a sloping well on a steep rock slope in a landfill as described in claim 2, characterized in that: The fixed pier is made of C20 plain concrete.

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