Hydraulic reclamation structure utilizing modified industrial solid waste and construction method
By using a layered dredging process that combines modified industrial solid waste with geopolymer-based cementitious materials, the problems of long consolidation cycles, high costs, large resource consumption, and environmental pollution in backfill remediation have been solved. This process achieves rapid consolidation and ecological restoration and is suitable for filling projects in complex geological conditions such as mining subsidence areas.
Patent Information
- Application Number
- CN202511980501.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-25
- Publication Date
- 2026-02-10
AI Technical Summary
Existing technologies for backfill remediation suffer from problems such as long consolidation cycles, high costs, large resource consumption, and high environmental pollution risks, making it difficult to achieve large-scale, low-cost, rapid consolidation and efficient solid waste disposal.
Modified industrial solid waste is mixed with geopolymer-based cementitious materials to form a fluid mixture. Through a layered dredging process, combined with a sealing structure consisting of an impermeable layer, a drainage layer, and a cover layer, rapid consolidation and ecological restoration are achieved.
It significantly shortened the consolidation period, reduced construction costs, improved the utilization rate of solid waste, ensured project stability and ecological safety, and is in line with the policy orientation of green and low-carbon development.
Smart Images
Figure CN121497418A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of industrial solid waste utilization technology, specifically to a dredging structure and construction method for utilizing modified industrial solid waste. Background Technology
[0002] The large-scale stockpiling of industrial solid waste (such as fly ash, coal gangue, metallurgical slag, and desulfurization gypsum) not only occupies valuable land resources, but the heavy metals and soluble salts they contain can also be leached and migrated by rainwater, posing a persistent and serious pollution risk to the surrounding soil, groundwater, and ecological environment. At the same time, major engineering activities such as energy extraction, port construction, and land reclamation in my country have created numerous geologically damaged areas, including mining subsidence areas, mined-out areas, abandoned mine pits, and tidal flats, which urgently require safe, economical, and efficient backfilling and ecological restoration. This provides a highly promising application scenario and a real need for the large-scale resource utilization of industrial solid waste.
[0003] Currently, the following two technical approaches are traditionally used for backfill remediation in the aforementioned areas: One method is traditional hydraulic reclamation, which typically uses water power to transport silt and sand dredged from rivers, lakes, and seas, or specially mined sand, to the area to be backfilled via pumps and pipelines. Its core relies on the physical sedimentation and drainage consolidation of the natural sand material itself. This process has inherent limitations: First, its consolidation period is extremely long, usually requiring months or even years of natural settlement and drying time to reach a certain foundation bearing capacity, severely restricting the progress of subsequent projects. Second, natural sand resources are increasingly scarce, and large-scale extraction damages riverbed and seabed ecosystems, while costs continue to rise. Finally, this technology achieves the "spatial transfer" of excavated soil but does not solve the problem of large-scale disposal of industrial solid waste, failing to reasonably align with the national strategic direction of "zero-waste city" construction and resource recycling.
[0004] Another method is cemented backfilling. In areas such as mine goaf remediation, grouting is a more common approach. This method typically uses cement or lime as the main cementing material, mixed with tailings, fly ash, etc., in a specific ratio before being injected into the goaf. While this method has been applied on a considerable scale, it still has significant drawbacks: First, traditional cement-based materials, when dealing with complex components and large-scale industrial solid waste, pose risks such as unstable solidification effects, subsequent strength reduction, or the leaching of harmful ions. Second, it is costly, with cement and other cementing materials accounting for 30%-60% of the total cost. The high cost of backfilling makes it difficult to promote large-scale, low-cost application in low-value-added or large-scale surface backfilling projects. Third, the production of cement and lime is a high-energy-consuming and high-carbon-emission process, and its extensive use contradicts the environmentally friendly concept of green development.
[0005] To address these challenges, researchers both domestically and internationally have begun exploring ways to utilize industrial solid waste for resource recovery. For example, they are combining industrial waste residue with natural mineral clay for rapid solidification of fill soil, or developing novel low-carbon fluidized bed materials using fly ash and slag as primary raw materials. While these technologies demonstrate the potential for industrial solid waste applications, most research remains in the experimental or localized application stage. Common problems include limited solid waste content, difficulty in processing raw solid waste, high cost of cementing materials, low early strength of the solidified body, and slow dehydration and consolidation efficiency. These limitations make it difficult to meet the engineering requirements for large-scale, low-cost, rapid consolidation, and efficient solid waste disposal.
[0006] Therefore, there is an urgent need for an innovative, scalable technological approach that can organically combine the large-scale disposal of bulk industrial solid waste with the efficient backfilling and restoration of large geological defects such as mining subsidence areas and sinkholes. Ideally, the technology should significantly reduce treatment costs while achieving large-scale solid waste disposal and aligning with national policies promoting green, low-carbon, and circular development.
[0007] Therefore, we propose a dredged filling structure and construction method utilizing modified industrial solid waste. Summary of the Invention
[0008] One of the technical problems this application aims to solve is the urgent need for an innovative, scalable technological approach that can organically combine the large-scale disposal of bulk industrial solid waste with the efficient backfilling and repair of large geological defects such as mining subsidence areas and sinkholes. Ideally, the technology should significantly reduce treatment costs while achieving large-scale solid waste disposal and aligning with national policies promoting green, low-carbon, and circular development.
[0009] To address the aforementioned technical problems, this application provides a dredged fill structure utilizing modified industrial solid waste, comprising an impermeable layer laid on a substrate; a multi-layered dredged fill body located above the impermeable layer, each layer of the dredged fill body being formed by layered consolidation of a mixture of modified industrial solid waste, with a single layer thickness of 0.3 meters to 1.2 meters; and a sealing structure covering the surface of the uppermost dredged fill body, the sealing structure comprising, from bottom to top, a drainage layer, an impermeable layer, and a soil cover layer.
[0010] In some embodiments, the impermeable layer is made of high-density polyethylene membrane or sodium bentonite waterproof blanket or a material with equivalent impermeability, and has a thickness of 0.5 mm to 2 mm.
[0011] In some embodiments, the modified industrial solid waste mixture is formed by crushing, grinding and sieving general industrial solid waste to obtain solid waste powder, and uniformly mixing the solid waste powder with geopolymer-based cementitious material at a predetermined mass ratio, and mixing with high-pressure water using a water pump; the general industrial solid waste includes one or more of fly ash, coal gangue, metallurgical slag and desulfurization gypsum, and the fineness of the solid waste powder is not greater than 80 mesh.
[0012] In some embodiments, the mass ratio of industrial solid waste to geopolymer-based cementitious material in the modified industrial solid waste mixture is 70-95:5-30.
[0013] In some embodiments, the consolidation strength of the dredged fill is not less than 5 kPa, and the layers are stacked one by one through a drainage process.
[0014] In some embodiments, the cover layer of the enclosure structure is a soil layer that can support vegetation restoration, with a thickness of not less than 0.3 meters.
[0015] In some embodiments, the main raw materials of the geopolymer-based cementitious material are slag, fly ash or metakaolin, and the proportion of active silica + alumina in the chemical composition is not less than 70%.
[0016] In some embodiments, a method for constructing a dredged fill structure using modified industrial solid waste includes the following steps: S1: laying an impermeable layer on the base of the dredged fill area; S2: General industrial solid waste is crushed, ground and sieved to obtain solid waste powder; S3: Mix solid waste powder and geopolymer-based cementitious material uniformly at a predetermined mass ratio to form a mixed powder. Use a water pump to add high-pressure water flow to mix with the mixed powder to form a blow-fill fluid mixture. S4: Use hydraulic conveying equipment to extract the dredged fluid mixture and transport it through pipelines to the dredged area for dredged filling operations; S5: After the single-layer dredged fluid mixture has initially solidified, the excess water that has precipitated in the upper layer of the dredged area is extracted or diverted out. S6: Repeat steps S4 to S5 to perform multiple layers of blast filling on the consolidated layer until the design elevation is reached; S7: Seal off the completed dredged area, including covering the surface of the dredged material with an impermeable layer, a drainage layer, and a backfill layer.
[0017] In some embodiments, the slump of the fluid mixture in S4 is controlled to be between 600 mm and 700 mm.
[0018] The present invention has at least the following beneficial effects: 1. During the project implementation, a fluid mixture is formed by industrial solid waste and geopolymer-based cementitious materials in a specific ratio. Combined with the layered dredging process, the consolidation cycle required by traditional dredging is significantly shortened. After drainage consolidation, the strength of each layer of dredging body in the range of 0.3 meters to 1.2 meters in thickness can quickly reach more than 5 kPa. The final consolidated body structure is dense, has strong integrity and high load-bearing capacity, which enables the subsequent layered construction to proceed continuously and avoids the construction period delays caused by the slow consolidation of traditional processes.
[0019] 2. In terms of resource utilization, this method uses industrial solid wastes such as fly ash and coal gangue as the main filler materials after crushing and grinding, replacing natural sand and gravel resources. This improves the utilization rate of industrial solid waste, which not only reduces the environmental damage risk of mining natural resources, but also solves the land occupation and pollution problems caused by solid waste stockpiling. The use of geopolymer-based cementitious materials further reduces the dependence on cement. Its active ingredients account for more than 70%, ensuring that the material can still provide effective bonding at a low dosage.
[0020] 3. The base impermeable layer uses high-density polyethylene membrane or sodium bentonite waterproof blanket, which effectively prevents potential pollutants in solid waste from migrating to the soil. During the layered consolidation process of the dredged fill, the slump is controlled within the range of 150 mm to 250 mm to reduce the risk of material segregation and release of harmful substances. The sealing structure adopts a composite design of impermeable layer, drainage layer and cover layer, which not only prevents rainwater infiltration from causing secondary pollution, but also enables rapid vegetation restoration through a cover layer with a thickness of not less than 0.3 meters, promoting the ecological reconstruction of the mining area.
[0021] 4. It is suitable for filling projects in complex geological conditions such as mining subsidence areas and goaf areas. While ensuring structural stability, it reduces the overall construction cost compared with traditional cement-based methods through material substitution and process optimization. The whole process takes into account multiple goals such as waste resource utilization, construction efficiency and ecological sustainability. Attached Figure Description
[0022] Figure 1 This is a schematic diagram of the blow-fill structure of the present invention; Figure 2 This is a schematic diagram of the construction steps of the hydraulic filling structure of the present invention; Figure 3 This is a general industrial solid waste crushing, grinding, and sieving process flow diagram for the present invention. Figure 4 This is a schematic diagram of the layered blowing process of the present invention; Figure 5 This is a schematic diagram of the drainage process of the present invention; Figure 6 This is a schematic diagram of the overall process of hydraulic reclamation construction according to the present invention.
[0023] In the diagram, 100 is the topsoil layer; 200 is the impermeable layer; 300 is the drainage layer; and 400 is the hydraulic fill. Detailed Implementation
[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0025] Example 1, see Figure 1 , 4 -6. The present invention provides a technical solution: a dredging structure utilizing modified industrial solid waste, including an impermeable layer 200 laid on a substrate; The multi-layered dredged fill 400 is located above the impermeable layer 200. Each layer of dredged fill 400 is formed by the layered consolidation of modified industrial solid waste mixture, and the thickness of a single layer is 0.3 meters to 1.2 meters. The sealing structure covering the surface of the uppermost dredged fill 400 includes, from bottom to top, a drainage layer 200, an impermeable layer 200, and a soil cover layer 100.
[0026] The impermeable layer 200 is made of high-density polyethylene membrane or sodium bentonite waterproof blanket or other materials with equivalent impermeability, with a thickness of 0.5 mm to 2 mm.
[0027] The modified industrial solid waste mixture is formed by crushing, grinding and sieving general industrial solid waste to obtain solid waste powder, and then uniformly mixing the solid waste powder with geopolymer-based cementitious material at a predetermined mass ratio, and then mixing with high-pressure water using a water pump. General industrial solid waste includes one or more of the following: fly ash, coal gangue, metallurgical slag, and desulfurization gypsum. The fineness of the solid waste powder is no greater than 80 mesh.
[0028] The mass ratio of industrial solid waste to geopolymer-based cementitious material in the modified industrial solid waste mixture is 70-95:5-30.
[0029] The consolidation strength of the 400-ton fill material is not less than 5 kPa, and the layers are stacked one by one through a drainage process.
[0030] The topsoil layer 100 of the enclosure structure is a soil layer that can support vegetation restoration, with a thickness of not less than 0.3 meters.
[0031] The main raw materials of geopolymer-based cementitious materials are slag, fly ash or metakaolin, and the proportion of active silica + alumina in the chemical composition is not less than 70%.
[0032] Specifically, the dredged fill structure uses an impermeable layer 200 to prevent the migration of potential pollutants from industrial solid waste into the base soil. A high-density polyethylene membrane or sodium bentonite waterproofing blanket with a thickness of 0.5 mm to 2 mm balances impermeability with material costs. The multi-layered dredged fill 400 employs a layered design with single layers ranging from 0.3 meters to 1.2 meters. This thickness range ensures that each layer of material achieves sufficient consolidation under drainage conditions while avoiding slow consolidation at the bottom due to excessive thickness. The technical requirement of a consolidation strength of not less than 5 kPa for the dredged fill 400 ensures sufficient load-bearing capacity between layers to support subsequent construction loads.
[0033] The modified industrial solid waste mixture uses industrial solid wastes such as fly ash and coal gangue, which are crushed and ground to a fineness of less than 80 mesh to enhance the material's reactivity. The solid waste powder is mixed with geopolymer-based cementitious materials at a mass ratio of 70-95:5-30. This ratio range maximizes solid waste utilization while ensuring cementing strength. The geopolymer-based cementitious materials contain at least 70% active silica and alumina to ensure effective activation of the cementing reaction of solid waste particles even at low dosages.
[0034] The enclosure structure employs a three-layer composite construction: a drainage layer (300m), an impermeable layer (200m), and a soil cover layer (100m). The drainage layer (300m) is located at the bottom for rapid drainage of surface water, the impermeable layer (200m) is centrally located to prevent rainwater infiltration and subsequent pollutant leaching, and the soil cover layer (100m) is designed with a thickness of at least 0.3 meters to meet the needs of vegetation root growth. Through the synergistic effect of material modification, layered consolidation, and enclosure protection, the overall structure achieves the dual goals of industrial solid waste resource utilization and ecological environment restoration.
[0035] The construction process of the hydraulic reclamation structure is as follows: This construction method begins with the pretreatment of the foundation of the hydraulic reclamation area. A 200mm impermeable layer is laid on the leveled and compacted foundation surface. The material used is a 0.5mm to 2mm thick high-density polyethylene film or sodium-based bentonite waterproof blanket to form a barrier against pollutant migration. Industrial solid waste raw materials are processed by crushing equipment; fly ash, coal gangue, and other materials are pulverized to a fineness below 80 mesh, ensuring that the particle size is no greater than 0.18mm. The resulting solid waste powder and geopolymer-based cementitious material are added to a mixing device at a mass ratio of 70-95:5-30, wherein the active silica and alumina content of the cementitious material is no less than 70%. During the mixing process, high-pressure water is injected through a water pump to control the slump to the range of 600mm to 700mm, forming a uniform fluid mixture.
[0036] A hydraulic conveying system pumps the fluid mixture through pipelines to the construction area for layered dredging operations. The thickness of each layer is strictly controlled between 0.3 and 1.2 meters, a design that balances consolidation efficiency and structural stability. After each layer is completed, it is allowed to solidify, and the upper free water is drained through drainage ditches or a vacuum preloading device. Once the consolidation strength reaches the 5 kPa threshold as determined by a field penetration test, the next layer is constructed. This layered, cyclical operation continues until the design elevation is reached, with the entire process of consolidation and drainage for each layer taking 4-8 hours.
[0037] After the hydraulic reclamation mass 400 is formed, the site is sealed off. A drainage layer 300, an impermeable layer 200, and a topsoil layer 100 are sequentially laid on the surface of the top hydraulic reclamation mass 400. The drainage layer 300 uses graded crushed stone or geogrid drainage mesh. The impermeable layer 200 uses materials consistent with the base impermeable layer 200. The topsoil layer 100 uses fertile soil and ensures a thickness of not less than 0.3 meters to support vegetation planting. The entire construction process, through the synergy of material modification optimization, layer thickness control, and consolidation strength monitoring, achieves the safe disposal of industrial solid waste and the restoration of land function.
[0038] Example 2, see Figure 1-6 This invention provides a method for constructing a dredged fill structure using modified industrial solid waste, comprising: S1: Lay a 1.5mm thick HDPE geomembrane at the bottom of the factory area. The specifications and performance are shown in Table 1 below. Table 1 HDPE Geomembrane Specifications
[0039] S2: General industrial solid waste is crushed and ground. First, it is coarsely crushed using a jaw crusher to reduce the particle size to below 50mm. Then, the coarsely crushed material is fed into a ball mill for dry grinding to further reduce the particle size. The ground material is then sieved through an 80-mesh vibrating screen. The material exceeding the screen size (particle size greater than 80 mesh) is returned to the ball mill for further grinding until all material particles are less than 80 mesh (see...). Figure 3 After the solid waste particles are smaller than 80 mesh, they are transported together with the geopolymer material to a non-powered homogenization device to homogenize the solid waste and the geopolymer material, thereby reducing the concentration of heavy metal ions in the solid waste leachate and significantly reducing the environmental pollution caused by solid waste.
[0040] S3: The homogenization material is filled by blowing sand through a sand blowing device.
[0041] Specifically, the sand blowing device consists of a sand collecting hopper, a filter screen, a mixing hopper, and a water pump. The homogenized material is transported to the sand hopper by a conveyor. After passing through the filter screen, impurities and particles with excessive size are filtered out. Then, the homogenized material enters the mixing hopper, where the water pump adds high-pressure water to mix with the homogenized material to form a water-material mixture. This mixture is then transported to the filling area via the sand blowing pipe connected to the sand blowing pump.
[0042] S4: After the water-based materials have settled in the factory area, use a water pump to remove the oozing water and repeat the construction process.
[0043] S5: After the fill height reaches the design elevation, cover the top with an HDPE membrane. The specifications and performance are shown in Table 1. Then, after covering with the membrane, constructing the protective layer and rainwater drainage layer, cover with soil ≥30cm to carry out land reclamation.
[0044] The HDPE membrane can be replaced with a sodium bentonite waterproof blanket.
[0045] Example 3, see Figure 1-6 A construction method for dredged landfill structures utilizing modified industrial solid waste, taking the implementation of a fly ash landfill project in northern Shaanxi as an example: S1: Lay a base layer and a 1.5mm thick high-density polyethylene (HDPE) impermeable layer 100 at the bottom of the landfill pit to be backfilled.
[0046] S2: Fly ash and geopolymer-based cementitious materials are uniformly mixed at a mass ratio of 90:10. Then, high-pressure water is added to the mixture using a water pump to obtain a fluidized fill mixture. To ensure good pumpability and self-leveling spreading properties, key rheological parameters are tested, and the solid-liquid ratio is controlled between 0.95 and 1.05; the slurry density is controlled between 1.65 and 1.75 g / cm³; simultaneously, during rapid on-site sampling and testing, the slump spread needs to be controlled within the range of 600-700 mm, and the initial setting time needs to be controlled within 4-8 hours to meet the continuity and stability requirements of layered construction. The prepared fluidized fill mixture is extracted using a sand pump and transported to the mining subsidence area through wear-resistant pipelines for fill operations. This operation adopts a layered fill method, with each layer controlled to a thickness of 1 m. After the fluid mixture of the single-layer dredged fill has initially solidified, its compressive strength is tested using a Fluke 2700G series standard digital pressure tester. When the compressive strength reaches no less than 5 kPa, the upper layer of precipitated water is pumped out. The cycle is repeated until the dredged fill reaches the design elevation +15.5m.
[0047] S3: After the dredged area is filled, the site will be sealed off, including covering the top of the dredged 400 with a 200-meter impermeable layer, then laying a 30cm layer of crushed stone as a drainage layer, and finally covering it with a planting soil of not less than 30cm to complete the land reclamation and restore the ecological function.
[0048] Example 4: This example aims to verify the practical application effect of the modified industrial solid waste dredging construction method provided by the present invention in a fly ash landfill project in Shanxi Province, and to conduct a comparative test between the dredging construction method of the present invention and the cement-based cemented filling method: Experimental Group: The method for dredging construction using modified industrial solid waste provided by this invention was adopted. Specifically, fly ash and geopolymer-based cementitious materials were uniformly mixed at a mass ratio of 90:10. Subsequently, high-pressure water and the mixed powder were added through a hydraulic conveying system to obtain a fluidized dredging mixture. The obtained fluidized dredging mixture was extracted using a sand-blowing pump and transported to the experimental group area through wear-resistant pipes for stratified dredging operations.
[0049] Control group: A traditional cement-based cementitious filling method was used, prioritizing engineering strength. Specifically, commonly available 42.5 grade ordinary Portland cement was mixed with fly ash. The mass ratio of fly ash to cement was 6:1 (i.e., 1 part cement to 6 parts fly ash, all by mass), and the water-cement ratio (i.e., the mass ratio of water to cement) was controlled at 0.6. The cement and fly ash were thoroughly premixed in a dry state, and a uniform fluid filling slurry was prepared by mechanical stirring. This slurry was also transported through pipelines to the control group area for layered filling operations.
[0050] After completing the dredging / filling operations using different methods, the dredging volume 400 in the two areas was monitored over a long period, and the following key indicators were tested and compared. The test data are shown in Table 2: Table 2 Comparison of key indicators between the method of the present invention and cement-based cementitious filling bodies.
[0051]
[0052] As can be seen from Table 2, the experimental group showed advantages over cement-based cementitious filling in several aspects: (1) The geopolymer system used in the method of the present invention has a faster early reaction and consolidation speed, and the single-layer consolidation time is significantly shortened, which is conducive to accelerating the construction progress.
[0053] (2) Although the cement-based cementitious filling body showed slightly higher compressive strength at 7 days and 28 days, the strength achieved by the method of the present invention fully meets the foundation bearing and stability requirements of fly ash landfills, and its strength growth trend is stable with good long-term performance.
[0054] (3) Since the method of the present invention mainly utilizes low-cost or cost-free industrial solid waste fly ash, and the cost of geopolymer activator is also lower than that of cement used in large quantities, the overall construction cost is significantly reduced, resulting in better economic benefits.
[0055] To further evaluate the environmental safety of landfills constructed using the method of this invention and cement-based cementitious backfill, multiple samples were randomly selected for heavy metal leaching toxicity tests after the backfill in each area had fully consolidated to 400 mm. The test results are shown in Table 3. Table 3 Comparison of heavy metal leaching concentrations in two types of backfill with national standards experimental group
[0056] Control group - cement-based cemented infill
[0057] As shown in Table 3, the pH and hexavalent chromium levels in the cement-based cementitious backfill exceeded the requirements of GB8978 standard. Therefore, the method of this invention can effectively ensure the environmental safety of landfill areas while realizing the resource utilization of industrial solid waste, avoiding potential pollution to soil and groundwater, and meeting the requirements of ecological environmental protection and sustainable development.
[0058] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.
[0059] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention.
Claims
1. A dredging structure utilizing modified industrial solid waste, characterized in that: Including the impermeable layer (200) laid on the base; The multi-layered dredged fill (400) located above the impermeable layer (200) is formed by layering and consolidating a modified industrial solid waste mixture, with a single layer thickness of 0.3 meters to 1.2 meters; The sealing structure covering the surface of the uppermost dredged fill (400) includes, from bottom to top, a drainage layer (200), the impermeable layer (200), and a soil cover layer (100).
2. The dredging structure and construction method utilizing modified industrial solid waste according to claim 1, characterized in that: The impermeable layer (200) is made of high-density polyethylene film or sodium bentonite waterproof blanket or other materials with equivalent impermeability, and has a thickness of 0.5 mm to 2 mm.
3. The dredging and filling structure and construction method utilizing modified industrial solid waste according to claim 1, characterized in that: The modified industrial solid waste mixture is formed by crushing, grinding and sieving general industrial solid waste to obtain solid waste powder, and then uniformly mixing the solid waste powder with geopolymer-based cementitious material at a predetermined mass ratio, and then mixing with high-pressure water using a water pump. The general industrial solid waste includes one or more of fly ash, coal gangue, metallurgical slag, and desulfurization gypsum, and the fineness of the solid waste powder is not greater than 80 mesh.
4. The dredging and reclamation structure and construction method utilizing modified industrial solid waste according to claim 3, characterized in that: The mass ratio of industrial solid waste to geopolymer-based cementitious material in the modified industrial solid waste mixture is (70-95):(5-30).
5. The dredging structure and construction method utilizing modified industrial solid waste according to claim 1, characterized in that: The consolidation strength of the dredged fill (400) is not less than 5 kPa, and the layers are stacked one by one through a drainage process.
6. The dredging and reclamation structure and construction method utilizing modified industrial solid waste according to claim 1, characterized in that: The soil cover layer (100) of the enclosure structure is a soil layer that can support vegetation restoration and has a thickness of not less than 0.3 meters.
7. The dredging and reclamation structure and construction method utilizing modified industrial solid waste according to claim 3, characterized in that: The main raw materials of the geopolymer-based cementitious material are slag, fly ash or metakaolin, and the proportion of active silica + alumina in the chemical composition is not less than 70%.
8. A method for constructing a dredged fill structure using modified industrial solid waste according to any one of claims 1-7, characterized in that: Includes the following steps: S1: Lay the impermeable layer (200) on the base of the reclamation area; S2: The general industrial solid waste is crushed, ground and sieved to obtain solid waste powder; S3: The solid waste powder and the geopolymer-based cementitious material are uniformly mixed at a predetermined mass ratio to form a mixed powder. High-pressure water is added using a water pump to mix with the mixed powder to form a blow-fill fluid mixture. S4: Use hydraulic conveying equipment to extract the dredged fluid mixture and transport it through pipelines to the dredged area for dredged filling operations; S5: After the single-layer blow-fill fluid mixture has initially solidified, the excess water that has precipitated in the upper layer of the blow-fill zone is extracted or diverted out. S6: Repeat steps S4 to S5 to perform multiple layers of blast filling on the consolidated layer until the design elevation is reached; S7: The completed dredged area is sealed off, including covering the surface of the dredged body (400) with the impermeable layer (200), the drainage layer (300) and the cover layer (100).
9. A method for constructing a dredged fill structure using modified industrial solid waste according to claim 8, characterized in that: The slump of the fluid mixture in S4 is controlled between 600 mm and 700 mm.