Landfill sludge pit sealing field covering support system and construction method thereof

Abstract

The present application belongs to the technical field of landfill sludge pit sealing engineering, and particularly relates to a landfill sludge pit sealing covering support system and a construction method thereof. The system comprises EPS plates, tenons, mortises, a coating layer and flat bamboos. The EPS plates are laid on the surface layer of the sludge pit, with the bottom surface in contact with the sludge layer and the top surface used for receiving the sealing covering structure; the adjacent EPS plates are detachably spliced by the tenon and mortise insertion cooperation; the coating layer is wrapped around the outer periphery of the plate body combination unit formed by splicing multiple EPS plates in the long edge direction, so as to integrate the EPS plates into an integrated combination unit; the flat bamboos are arranged between the coating layer and the EPS plates, and used for supporting the EPS plates. During construction, the lower layer of the coating layer is laid first, then the EPS plates are spliced, and finally the coating layer is reversely wrapped around the outer periphery of the upper layer of the EPS plate combination and fixed at the lapping position. The present application replaces the traditional sludge solidification treatment scheme with a support system, and a stable sealing bearing platform can be formed without solidification of the sludge, with the advantages of short construction period, low engineering cost and high bearing capacity.

Description

Technical Field

[0001] This invention belongs to the field of landfill sludge pit sealing engineering, and specifically relates to a landfill sludge pit sealing and covering support system and its construction method. Background Technology

[0002] For decades, municipal solid waste in my country has primarily been disposed of through sanitary landfills. Currently, many of the early-built landfills have reached their designed service life and are entering the closure and remediation phase, making landfill closure an urgent matter. Due to limitations imposed by early disposal processes and historical conditions, older landfills commonly contain large amounts of sludge. This sludge has a high water content and extremely low carrying capacity, making its safe disposal a core technical challenge that urgently needs to be addressed in landfill closure projects.

[0003] Currently, in the field of landfill sludge pit closure projects, the conventional approach is to first solidify and stabilize the sludge in the pit. This solidification process increases the sludge's strength to meet required standards before closure construction is carried out in conjunction with the municipal solid waste storage area. However, this solidification method has significant shortcomings: firstly, the solidification process is complex, has a long curing period, and results in a lengthy overall construction period; secondly, it requires large quantities of solidification materials and significant machinery investment, leading to high project costs, and the construction layout is easily constrained by the site's spatial conditions. These issues make it difficult for traditional solidification closure technology to balance feasibility and economy. Currently, the industry lacks a support structure system that can directly improve the load-bearing capacity of sludge pits without relying on the sludge's own solidification. Summary of the Invention

[0004] To address the aforementioned problems, this invention proposes a landfill sludge pit sealing and support system and its construction method. By constructing a support system within the sludge pit to replace traditional sludge pit solidification treatment methods, the goal of shortening the construction period, reducing costs, and increasing load-bearing capacity is achieved.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A landfill sludge pit sealing and covering support system includes: EPS boards are laid on the surface of the sludge pit in the landfill, with the bottom surface in contact with the sludge layer surface and the top surface used to support the landfill covering structure. The EPS board is assembled with adjacent EPS boards by horizontal and / or vertical butt joints using tenons and mortises. The tenons are inserted into the matching mortises to achieve detachable assembly. The covering layer is wrapped around the periphery of the board assembly unit formed by assembling multiple EPS boards along the long side, thereby forming an integrated assembly unit of the EPS boards. Flat bamboo is placed between the covering layer and the EPS board as a supporting component for the EPS board.

[0006] Furthermore, the density of the EPS board is less than that of the sludge, and it relies on its own buoyancy to support the sealing and covering structure.

[0007] Furthermore, the tenons and mortises are symmetrically arranged on each side of the EPS board; the tenons and mortises are integrally formed with the EPS board, and the tenons and mortises on adjacent sides of the same EPS board are arranged alternately.

[0008] Furthermore, the covering layer is a geogrid with a perforated mesh structure.

[0009] Furthermore, the flat bamboo (as a connector) is clamped between the interlaced reinforcing bars of two adjacent geogrids.

[0010] Furthermore, at the overlap position of the covering layer, adjacent geogrids are fixed together by inserting their reinforcing bars.

[0011] Furthermore, the flat bamboo is a long strip-shaped connecting member that can replace steel bars.

[0012] Correspondingly, a construction method for a landfill sludge pit sealing and covering support system, using the support system described above, includes the following steps: After the surface water in the sludge pit is drained, the specifications and layout parameters of the EPS boards are determined based on the area and depth of the sludge pit and the design thickness of the sealing and covering system. Lay the lower layer of the covering layer; then lay EPS boards sequentially on the covering layer along the side of the sludge pit, and assemble adjacent EPS boards by interlocking the tenons and mortises in the horizontal and / or vertical directions. Multiple EPS boards are used as an assembly unit. After assembling a unit, the covering layer is wrapped upwards around the outer periphery of the upper layer of the EPS board assembly to form an integrated assembly unit. The covering layer forms a closed loop structure and is fixedly connected at the overlapping parts. The number of widths of the closed loop covering layer determines the coverage range. The specific number of widths is determined based on the EPS board specifications and on-site tests.

[0013] Furthermore, after laying the lower layer of the covering layer, the flat bamboo (as a connector) is first clamped between the interlaced reinforcing bars of two adjacent geogrids, and then an assembly unit composed of multiple EPS boards is assembled on top of the lower layer of the covering layer.

[0014] Furthermore, the assembly and covering of each assembly unit are carried out in sequence from near to far, until the EPS board is fully laid in the sludge pit operation area.

[0015] Compared with the prior art, the present invention has the following beneficial technical effects: This invention constructs a support system directly within the sludge pit, forming a stable sealing platform without the need for sludge solidification. The sludge remains undisturbed, significantly shortening the construction cycle and reducing material and machinery costs. It also avoids the stringent requirements of large-scale solidification operations on site space conditions, achieving a dual improvement in construction efficiency and economy.

[0016] The EPS board has a lower density than sludge, allowing it to provide upward support through its own buoyancy. A geogrid covering layer on the outside of the EPS board restrains the board, effectively limiting vertical settlement and horizontal displacement caused by the board and the upper sealing and covering system. Flat bamboo is placed between the covering layer and the EPS board and embedded between the geogrid reinforcement bars, further supporting the EPS board and improving the load-bearing capacity of the entire support system. Relying on the synergistic load-bearing mechanism of each component, this support system can maintain the stability of the sealing and covering system under sludge conditions with high moisture content and extremely low load-bearing capacity.

[0017] The EPS board adopts a one-piece injection-molded mortise and tenon structure, with tenons and mortises arranged in an interlaced pattern on all four sides, supporting multi-directional seamless splicing. The board is detachable, and the assembly method is simple and highly versatile. The geogrid covering layer wraps around the EPS board unit along its long side, and the overlap is fixed by inserting the reinforcing bars of adjacent geogrids. Combined with the site closure and covering system, the geotextile and EPS board unit is fixed and anchored to the lower part of the drainage ditch around the reservoir area, which greatly improves the overall stability of the support system.

[0018] This invention optimizes and integrates the components, creating a unified layout. The resulting sludge pit sealing and covering support system enables the coordinated action of each unit, resulting in a scientifically structured overall force system, significantly improved overall structural rigidity and stability, and remarkable load-bearing and limiting protection effects. Attached Figure Description

[0019] Figure 1 This is a three-dimensional model diagram of a landfill sludge pit sealing and covering support system according to the present invention; Figure 2 This is a structural diagram of the EPS board with tenons according to the present invention; Figure 3 This is a structural diagram of the EPS board with tenons according to the present invention; Figure 4 This is a schematic diagram of the connection between connected EPS boards according to the present invention; Figure 5 This is a schematic diagram of the coating layer of the present invention; Figure 6 This is a schematic diagram of the overlapping and fixing of the coating layer of the present invention; Figure 7 This is a cross-sectional schematic diagram of the support system for field application of the present invention.

[0020] The numbers in the diagram are: 1. EPS board; 2. tenon; 3. mortise; 4. covering layer; 5. flat bamboo. Detailed Implementation

[0021] The technical solutions in the embodiments of the present invention will now be described in detail and completely with reference to the accompanying drawings. Obviously, the described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0022] Please see Figure 1 This invention provides a landfill sludge pit sealing and support system, comprising an EPS board 1, tenons 2, mortises 3, a covering layer 4, and flat bamboo 5. The EPS board 1 is made of polystyrene foam and has a uniform flat structure. The EPS board 1 has a lower density than sludge, providing buoyancy support. It possesses low density, corrosion resistance, and high toughness, making it suitable for sludge pit conditions with high water content and easy settling.

[0023] Please see Figures 2-4 EPS board 1 is laid on the surface of the sludge pit in the landfill, with its bottom surface in contact with the sludge layer surface and its top surface used to support the landfill covering structure. Tenons 2 are made of polystyrene foam and are fixed to the four edges of EPS board 1. Tenons 2 and matching mortises 3 are interlocked to allow for the detachable splicing of adjacent EPS boards 1. Tenons 2 and mortises 3 are symmetrically arranged on each side of EPS board 1, and the tenons 2 and mortises 3 on adjacent sides of the same EPS board 1 are staggered to meet the requirement of multi-directional seamless splicing. Preferably, tenons 2 and mortises 3 are integrally injection molded with EPS board 1.

[0024] Please see Figure 5 The covering layer 4 uses geogrid, which wraps around the periphery of the panel unit formed by assembling multiple EPS boards 1 along its long side. The number of EPS boards 1 assembled is determined according to the actual length and width of each geogrid panel on site, forming an integrated unit of EPS boards 1, thereby improving the overall load-bearing capacity and structural stability of the support system. At the overlap positions of the covering layer 4, adjacent geogrid panels are fixed together by their reinforcing bars, further improving the overall stability of the covering layer 4.

[0025] Please see Figure 6 Flat bamboo 5 is a long strip connecting component that can replace steel bars. It is sandwiched between the interlaced reinforcing bars of two adjacent geogrids and is placed between the covering layer 4 and the EPS board 1 to support the EPS board 1, thereby improving the overall load-bearing capacity and structural stability of the support system.

[0026] In the actual construction process, before sealing the landfill sludge pit, the surface water of the sludge pit is first drained. Based on the actual area and depth of the sludge pit and the designed thickness of the sealing cover system, a small-scale field test is conducted first to determine the specifications, dimensions, quantity, location, and performance parameters of the EPS board 1.

[0027] Based on the location, construction begins at the edge of the sludge pit. Specifically, first, the lower layer of geogrid covering layer 4 is laid, then flat bamboo 5 (as connectors) is clamped between the interlocking reinforcing bars of adjacent geogrids. Subsequently, an assembly unit consisting of multiple EPS boards 1 is assembled on top of the lower layer of covering layer 4. Adjacent EPS boards 1 are joined laterally and / or longitudinally using tenon 2 and mortise 3 interlocking.

[0028] Multiple EPS boards 1 are used as an assembly unit. After assembling one unit, the covering layer 4 is wrapped upwards around the outer perimeter of the EPS board 1 assembly, forming an integrated assembly unit. The covering layer forms a closed-loop structure, and the overlapping parts are fixedly connected. The number of widths of the closed-loop covering layer determines the coverage area, and the specific number of widths is determined based on the EPS board specifications and on-site tests. The assembly and covering of each assembly unit are carried out sequentially from near to far until the EPS boards 1 are fully laid in the sludge pit operation area.

[0029] The specific working process of this support system is as follows: Please see Figure 7 After the support system is installed, geotextile is laid on top and fixed to the system. This serves both as an isolation and reinforcement mechanism, and the geotextile is anchored to the bottom of the drainage ditches surrounding the landfill area. Then, backfill with earth or other lightweight filler to create a slope, ensuring the slope meets the required drainage standards. After the slope is created, the landfill capping system is constructed sequentially, connecting the sludge pit area with the capping structure of the rest of the landfill area, thus completing the landfill capping construction for the entire landfill area.

[0030] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A landfill sludge pit sealing and support system, characterized in that, include: EPS board (1) is laid on the surface of the sludge pit in the landfill, with the bottom surface in contact with the surface of the sludge layer and the top surface used to support the landfill cover structure. The EPS board (1) is assembled with the adjacent EPS board (1) by horizontal and / or vertical jointing through tenons (2) and mortises (3). The tenons (2) are inserted into the matching mortises (3) to achieve detachable assembly. The covering layer (4) is wrapped around the outer periphery of the board assembly unit formed by assembling multiple EPS boards (1) along the long side direction, thereby forming the EPS boards (1) into an integrated assembly unit. Flat bamboo (5) is placed between the covering layer (4) and the EPS board (1) as a supporting component of the EPS board (1).

2. The landfill sludge pit sealing and covering support system according to claim 1, characterized in that, The EPS board (1) has a lower density than the sludge and relies on its own buoyancy to support the sealing and covering structure.

3. The landfill sludge pit sealing and covering support system according to claim 1, characterized in that, The tenons (2) and mortises (3) are symmetrically arranged on each side of the EPS board (1); the tenons (2) and mortises (3) are integrally formed with the EPS board (1), and the tenons (2) and mortises (3) on adjacent sides of the same EPS board (1) are arranged alternately.

4. The landfill sludge pit sealing and covering support system according to claim 1, characterized in that, The covering layer (4) is a geogrid with a perforated mesh structure.

5. The landfill sludge pit sealing and covering support system according to claim 4, characterized in that, The flat bamboo (5) is embedded inside the covering layer (4) and sandwiched between the interlocking reinforcing bars of two adjacent geogrids.

6. The landfill sludge pit sealing and covering support system according to claim 4, characterized in that, At the overlap position of the covering layer (4), the adjacent geogrids are fixed by inserting their reinforcing bars.

7. The landfill sludge pit sealing and covering support system according to claim 1, characterized in that, The flat bamboo (5) is a long strip connecting member that can replace steel bars.

8. A construction method for a landfill sludge pit sealing and support system, characterized in that, The support system described in any one of claims 1 to 7 includes the following steps: After the surface water in the sludge pit is drained, the specifications and layout parameters of the EPS board (1) are determined according to the area, depth and design thickness of the sludge pit and the sealing and covering system. First, lay the lower layer of the covering layer (4), and then lay EPS boards (1) sequentially along the side of the sludge pit on the covering layer (4). The adjacent EPS boards (1) are assembled horizontally and / or vertically by interlocking the tenons (2) and the mortises (3). Multiple EPS boards (1) are used as an assembly unit. After assembling a unit, the covering layer (4) is wrapped around the outer periphery of the upper layer of the EPS board (1) assembly to form an integrated assembly unit. The covering layer (4) forms a closed loop structure and is fixedly connected at the overlapping part. The number of layout widths of the closed loop covering layer (4) determines the coverage range. The specific number of layout widths is determined according to the specifications of the EPS board (1) and on-site tests.

9. The construction method of the landfill sludge pit sealing and covering support system according to claim 8, characterized in that, After laying the lower layer of the covering layer (4), the flat bamboo (5) is first clamped between the interlocking reinforcing bars of two adjacent geogrids, and then an assembly unit composed of multiple EPS boards (1) is assembled on the upper layer of the lower layer of the covering layer (4).

10. The construction method of the landfill sludge pit sealing and covering support system according to claim 8, characterized in that, The assembly and covering of each assembly unit are carried out in the order of construction from near to far until the EPS board (1) is fully laid in the sludge pit operation area.

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