A modular device for in-situ inhibition of river and lake sediment disturbance and method of use thereof

Abstract

This invention discloses a modular device and its application method for in-situ suppression of sediment disturbance in rivers and lakes, relating to the field of aquatic ecological environment. The device includes a grid structure module and a flexible connection mechanism: the grid structure module consists of primary / secondary keel grid strips connected by interlocking slots, with outer edge sealing strips; the flexible connection mechanism engages with a spherical fixing element via a fixing slot with a hooked arc-shaped elastic body and an internal spring, allowing the module to deflect horizontally by ±5° and move vertically by ±3cm; the bottom of the module is equipped with a retractable support to adapt to different sediment thicknesses; the application method includes surveying and mapping, module calculation, assembly and deployment, and maintenance. This invention suppresses sediment resuspension by physically fixing sediments and mitigating water flow disturbance, offering advantages such as low cost, simple construction, and eco-friendliness, making it suitable for river and lake sediment pollution control and ecological restoration.

Description

Technical Field

[0001] This invention relates to the field of aquatic ecological environment, and in particular to a modular device for in-situ suppression of disturbance of river and lake bottom sediments and its usage method. Background Technology

[0002] Bottom sediment generally refers to the sediments in freshwater bodies of rivers and lakes, and is an important component of water bodies, serving as a source and sink of energy and nutrients. Disturbance of river and lake bottom sediment can impact water quality and ecosystems. On the one hand, it increases the concentration of suspended solids in the water, reducing water transparency and thus affecting light transmittance. On the other hand, disturbed and resuspended sediment releases nutrients, promoting algal growth and potentially leading to eutrophication. Appropriate sediment disturbance and resuspension can provide nutrients for aquatic organisms and promote primary productivity. However, excessive sediment disturbance inhibits algal photosynthesis, reduces primary productivity, and consequently affects the stability and biodiversity of the entire lake ecosystem. The causes of sediment disturbance are usually related to disturbance by benthic organisms (fish, shellfish, etc.), vessels, wind-driven currents, and river / lake current disturbances. Benthic organisms alter water and sediment fluxes at the water-sediment interface through their activities (such as burrowing, movement, and feeding), significantly impacting microbial activity and biogeochemical processes within the sediment. Ship traffic violently agitates water, causing sediment disturbance and resuspension, increasing suspended solids concentration and reducing water transparency. Wind-driven currents (wind-driven currents) can induce vertical and horizontal water movement, leading to sediment resuspension. The shear and impact forces of flowing water can overcome the gravity and adhesion of sediment particles, suspending them in the water. These complex disturbances not only increase suspended solids concentration and reduce water transparency in rivers and lakes but also potentially damage benthic habitats, thereby affecting the stability and biodiversity of the entire aquatic ecosystem. Therefore, addressing or reducing the problem of sediment disturbance and resuspension in lakes is crucial for improving water quality and ecological restoration.

[0003] Currently, the main methods for addressing the resuspension of disturbed lake sediments include in-situ sediment covering, lakebed dredging, flocculant addition, planting submerged plants, and ecological dredging. However, these methods suffer from significant drawbacks, such as damaging benthic habitats, high costs, difficult construction, unstable covering effects, high cost of amendments, and the potential for secondary pollution. Therefore, there is an urgent need for a low-cost, easy-to-construct, and minimally impactful in-situ sediment disturbance suppression device. Summary of the Invention

[0004] To solve the above-mentioned technical problems, the first objective of this invention is to provide a modular device for in-situ suppression of disturbance of river and lake bottom sediments, and the second objective is to provide a method for using the modular device for in-situ suppression of disturbance of river and lake bottom sediments.

[0005] To achieve the first objective of this invention, the present invention proposes a technical solution for a modular device for in-situ suppression of disturbance of river and lake bottom sediments, comprising: Grid structure module: formed by the cross connection of main keel grid strips and secondary keel grid strips through slots, with the outer edge encapsulated by edge banding strips; Flexible connection mechanism: includes a fixing slot and a ball fixing element. The fixing slot is located at the end of the edge banding strip and is composed of a pair of arc-shaped elastic bodies with barbs. The elastic bodies have built-in springs. The ball fixing element is located at the end of the edge banding strip corresponding to the fixing slot position of the adjacent module. After matching and engaging with the fixing slot of the adjacent module, it forms a deflectable flexible connection mechanism. The grid structure modules are interlocked by a flexible connection mechanism to form a mesh modular device that can adapt to the complex terrain at the bottom of rivers and lakes. The bottom of the grid structure module is equipped with a retractable support to adapt to different sediment thicknesses. By physically fixing the sediment and reducing water flow disturbance, it effectively inhibits the resuspension of river and lake sediment.

[0006] Furthermore, the radius of curvature of the arc-shaped elastic body of the fixed slot is 5~10cm, the barb depth is 5mm, the spring preload is 5~8N, and after engaging with the ball fixing element, it allows the adjacent module to deflect horizontally by ±5° and vertically by ±3cm.

[0007] Furthermore, the width ratio between the widest part of the sphere fixing element and the widest part of the fixing slot opening is 1:1.2. The lower half of the sphere fixing element is provided with a chamfer, and the edge of the chamfer complements and locks with the barb structure of the fixing slot to prevent slippage after locking.

[0008] Furthermore, the length of the telescopic bracket is adjustable, with an adjustment range of 0~50cm, and it is fixed by a locking mechanism with a locking strength ≥500N.

[0009] Furthermore, the telescopic bracket includes an inner rod and an outer tube, and its length is adjusted via a pin hole and a spring pin.

[0010] Furthermore, the main keel, secondary keel, and edge strip are made of polyvinyl chloride (PVC) or polypropylene (PP), with a thickness of 10mm, a length of 2.5~5m, and a height of 20~40cm.

[0011] To achieve the second objective of this invention, this invention proposes a technical solution for a method using the aforementioned modular device for in-situ suppression of river and lake sediment disturbance, comprising the following steps: S1. Water area survey and topographic mapping: Determine the survey scope, investigate water level changes, measure bottom sediment thickness, measure water flow and water quality indicators; S2. Module Quantity Calculation: Based on the underwater area and the coverage area of ​​a single module, the quantity is calculated using the formula "Module Quantity = Underwater Area / Single Module Area × Redundancy Coefficient". S3. Module assembly and splicing: The main / secondary keel is connected by slots, the edge strip is encapsulated by mortise and tenon structure, and adjacent modules are flexibly spliced ​​with the spherical fixing element through the fixing slot; S4. Transportation and Deployment: Adjust the length of the telescopic support according to the thickness of the bottom sediment, select a suitable ship transportation device, and deploy the module to the target water area through the positioning system, controlling the deployment speed and attitude; S5. Post-installation inspection: Use visual inspection, underwater photography, ROV or multibeam sonar to check the installation quality; S6. Maintenance and Management: Regularly inspect the structural integrity and environmental impact, repair and reinforce damaged parts, and assess the impact of water flow on the device annually.

[0012] Furthermore, the water area survey and underwater topographic mapping described in step S1 include: a. The scope of the survey is determined by geographic coordinate mapping, with a boundary coordinate accuracy of ±0.01° and an area calculation error of ≤2%; b. The water level changes are monitored in real time by a pressure level gauge once per hour, and are compared with historical hydrological data for at least one year to obtain the annual average water level, the highest water level and the lowest water level. c. The sediment thickness is measured using a combination of high-precision echo sounding and sediment sampling to create a sediment isopyrograph, wherein: Depth measurement resolution ≤ ±2cm, sediment sampling point density ≥ 1 point / 100m²; The sediment thickness data is used to determine the length of the telescopic support, ensuring that the distance between the bottom of the module and the surface of the sediment is ≥10cm. d. The water flow measurement is performed using an Acoustic Doppler Current Profiler (ADCP) with vertical stratification. Specific parameters include: Flow velocity measurement range: 0.01~5m / s; flow direction accuracy: ±3°; vertical stratification thickness: 0.5m. At least the spatiotemporal variation patterns of water flow during the high-water season, low-water season, and normal-water season should be obtained to assess the scouring effect of water flow on the modular unit structure.

[0013] Furthermore, step S2, "module number calculation," includes: a. Area calculation for regular regions: using geometric formulas, rectangle: length × width; circle: πr²; b. Calculation of irregular area: Use a 1m×1m grid method with a grid coverage of ≥95% or a CAD planimeter with an area fitting error of ≤2%; c. Module layout design: When the bottom slope is ≤15°, a uniform square layout is adopted with a module spacing of 0.5~1m; when the slope is >15°, the module spacing is increased by 20% and arranged along the contour line direction.

[0014] Furthermore, the materials of the main and secondary keel grid strips mentioned in step S3 are selected according to the degree of water pollution in the water area, including: a. When the water pollution level is mild, the main keel and secondary keel should be made of recyclable materials; b. When the water pollution level is moderate to severe, the main keel and secondary keel shall be made of pollutant-adsorbing composite material; c. When there is a need for ecological restoration in the water area, the surface of the main keel and secondary keel is covered with a biological seed coating layer.

[0015] Furthermore, the transportation and delivery described in step S4 includes: a. Vessel selection: Select based on a safety factor of 1.5 for the total weight of the modules, with a deck load capacity ≥3t / m² and a crane lifting capacity ≥20t; b. Deployment and positioning: DGPS + USL (Ultra-Short Baseline) joint positioning is adopted, with a horizontal positioning error of ≤0.5m, a deployment speed of 0.2~0.3m / s, and a tilt angle of ≤10°.

[0016] Furthermore, the post-installation check described in step S5 includes: a. Shallow water area inspection: Confirm the secure connection of the device by visual inspection or touch, ensuring there is no loosening or displacement; b. Deep water area inspection: Using an ROV equipped with a 2-megapixel camera, illumination intensity ≥5000 lux or multi-beam sonar, point cloud density ≥5 pts / m², to detect surface defects and coverage integrity of the equipment.

[0017] Furthermore, the maintenance management described in step S6 includes: a. Regular inspections: Quarterly structural stability checks are conducted using underwater photography or ROV, and annual assessments are made of the impact of water flow erosion on module spacing. b. Repair and reinforcement: Reinforce deformed grid strips, and re-press or replace loose connection nodes.

[0018] The beneficial effects achieved by this invention are as follows: 1. Effectively inhibits sediment resuspension The grid structure blocks sediment particle movement through physical fixation, while slowing water flow velocity, reducing hydrodynamic shear force, and minimizing the risk of sediment resuspension; the flexible connection design allows the modules to adapt to terrain undulations, ensuring a close fit with the sediment surface and improving cover stability.

[0019] 2. Adaptable to complex river and lake terrain The telescopic support adjusts its height according to the thickness of the bottom mud to prevent the module from sinking into the silt; the flexible connection mechanism allows for horizontal deflection of ±5° and vertical displacement of ±3cm, adapting to changes in slope and gully terrain.

[0020] 3. Low cost and ease of construction The modular design supports on-site assembly without the need for large equipment; the main and secondary keels are made of PVC / PP material, which costs only 1 / 3 to 1 / 2 of traditional dredging technology and is recyclable; the construction process is simple, and 1,000 to 2,000 m² of water area can be laid in a single day, with minimal impact from the weather.

[0021] 4. Eco-friendly and sustainable The material is resistant to acid and alkali corrosion and does not release harmful substances; the grid structure does not hinder the water-sediment material cycle and does not affect the growth of aquatic plants or the habitat of benthic organisms.

[0022] 5. Long-term stability and low maintenance The structural nodes have a shear strength of ≥5kN and a locking force of ≥500N, ensuring long-term operational stability; quarterly ROV testing combined with annual water flow scour assessment results in low maintenance costs. Attached Figure Description

[0023] Figure 1 This is a three-dimensional side view of the mesh structure module in Embodiment 1 of the present invention.

[0024] Figure 2 This is a top view schematic diagram of the grid structure module of Embodiment 1 of the present invention.

[0025] Figure 3 This is a top view of the mesh structure modules of Embodiment 1 of the present invention, which are connected by a flexible connection mechanism to form a mesh modular device.

[0026] Figure 4 This is a side view of the fixed slot structure of Embodiment 1 of the present invention.

[0027] Figure 5 for Figure 3 A partial enlarged view of part A (flexible connection mechanism).

[0028] Figure 6 This is a flowchart illustrating the steps of using the modular device according to Embodiment 1 of the present invention.

[0029] In the picture: 1. Main keel grid strip; 2. Secondary keel grid strip; 3. Edge banding strip; 4. Slot; 5. Tenon; 6. Telescopic bracket; 7. Fixed slot; 7-1. Fixed slot base; 7-2. Fixed slot inner wall; 7-3. Slot head; 7-4. Slot head sliding hook; 8. Ball fixing element; 8-1. Snap-fit ​​post; 8-2. Arc-shaped snap-fit ​​connector; 8-3. Snap-fit ​​connector sliding hook; 9. Spring. Detailed Implementation

[0030] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, it should be noted that, for ease of description, only the parts relevant to this application are shown in the accompanying drawings, not the entire structure. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this application.

[0031] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0032] This invention provides a modular device for in-situ suppression of disturbance of river and lake bottom sediments, including a grid structure module. The grid structure module is interlocked with each other through a flexible connection mechanism to form a mesh modular device, which can adapt to the complex topography of the river and lake bottom. The bottom of the grid structure module is provided with a retractable support, which can adapt to different sediment thicknesses. By physically fixing the sediments and slowing down the disturbance of water flow, it effectively suppresses the resuspension of river and lake bottom sediments. The grid structure module is formed by the main keel grid strips and the secondary keel grid strips being connected by slots, and the outer edge is encapsulated by the edge banding strip. The flexible connection mechanism includes a fixing slot and a ball fixing element. The fixing slot is located at the end of the binding strip and is composed of a pair of arc-shaped elastic bodies with barbs, and the elastic bodies have built-in springs. The ball fixing element is located at the end of the binding strip corresponding to the fixing slot position of the adjacent module. After matching and engaging with the fixing slot of the adjacent module, it forms a deflectable flexible connection mechanism.

[0033] The grid structure module includes: main keel grid strips, secondary keel grid strips, edge banding strips, slots, tenons, fixing slots, spherical fixing elements, and springs. Main and secondary keels: The main keel is usually vertically installed, serving as the main load-bearing component of the module unit. It is responsible for bearing the vertical load and part of the horizontal load of the entire module unit structure. Its cross-sectional dimensions and material strength must meet the load-bearing requirements to ensure the stability of the module unit. The secondary keel is horizontally fixed to the main keel, serving to connect and support the module unit panels. Through its vertical intersection with the main keel, it together forms the basic support frame of the module unit, giving the module unit good structural rigidity and deformation resistance, effectively distributing and transferring loads, and ensuring the safety and reliability of the module unit during use. Edge banding strips can enhance the strength of the module unit panel edges, preventing edge deformation or damage, and also facilitating the splicing between modules.

[0034] The main keel grid strip can be made of one or more plastic materials such as polyvinyl chloride (PVC), polypropylene (PP), polystyrene-acrylate copolymer (PSAC), polytetrafluoroethylene (PTFE), polyethylene (PE), polystyrene (PS), polyethylene terephthalate (PET), polymethyl methacrylate (PMMA), polyetheretherketone (PEEK), acrylonitrile-butadiene-styrene copolymer (ABS), polyacrylic rubber, thermoplastic polyurethane elastomer (PU thermo), phenolic plastics, polyester resins, and epoxy resins. The main keel grid strip is 10 mm thick, 2.5~5 m long, and 20~40 cm high. Its thickness, length, and height can be adjusted according to the actual application scenario. A 10 cm wide slot is provided every 50~100 cm on the main keel grid strip to facilitate subsequent on-site assembly with the secondary keel grid strip. Tenon structures are provided at both ends of the main keel grid to fix it to the edge banding strip.

[0035] The secondary keel grating strips can also be made of one or more plastic materials such as polyvinyl chloride (PVC) and polypropylene (PP). The secondary keel grating strips are 10 mm thick, 2.5~5 m long, and 20~40 cm high, and their thickness, length, and height can be adjusted according to the actual application scenario. A 10 cm wide slot 4 is provided every 50~100 cm on the secondary keel grating strip to facilitate subsequent on-site splicing with the main keel grating strip. Tenon structures are provided at both ends of the secondary keel grating strip to allow for fixed connection with the edging strip.

[0036] The edging strip can be made of one or more plastic materials such as polyvinyl chloride (PVC) and polypropylene (PP). The edging strip is 10 mm thick, 2.5–5 m long, and 20–40 cm high; its thickness, length, and height can be adjusted according to the actual application scenario. The edging strip is connected and fixed to the main and secondary keel grid strips via mortise and tenon joints. Modules are directly connected and fixed to each other via fixing slots and spherical fixing elements.

[0037] The lower part of the grid structure module is equipped with a retractable support. The retractable support can be made of metal materials (304 stainless steel, 316 stainless steel, galvanized steel wire, etc.) to ensure its reliability and safety during use.

[0038] The fixing slot can be made of plastic materials (Nylon 66 (PA66), Nylon 6 (PA6), polypropylene (PP), polyethylene (PE), polyvinyl chloride (PVC), polyester (PET), PVC-coated iron wire, PE-coated iron wire), etc., or metal materials (304 stainless steel, 316 stainless steel, galvanized steel wire), etc. The diameter of the ball fixing element can be adjusted according to the width of the slot, ensuring the reliability and safety of both during use.

[0039] This invention also provides a method for using a modular device for in-situ suppression of disturbance of river and lake bottom sediments, comprising the following steps: I. Water Area Survey and Underwater Topographic Mapping (1) Survey preparation Define the scope of the survey: Determine the geographical coordinates of the surveyed water area, including the boundary coordinates of the four directions of east, south, west, and north, as well as the total area of ​​the water area; Water level change survey: Collect water level change data of water bodies, including the annual average water level, the highest water level, the lowest water level, and the period and magnitude of water level changes; Bottom silt thickness survey: A comprehensive investigation of the spatial distribution and thickness of the lakebed silt will be conducted using a combination of high-precision echo sounding and sediment sampling. The survey will create isopyrographs of the lakebed silt to determine the length of the module's retractable support structure, ensuring the module is not covered by silt.

[0040] (2) Underwater topographic mapping Equipment selection: High-precision mapping is carried out using equipment such as multibeam echo sounders, single-beam echo sounders, and side-scan sonar.

[0041] Data Acquisition: Obtain three-dimensional data of underwater topography, including information such as underwater undulations, gullies, and slopes, and draw detailed underwater topographic maps.

[0042] Water flow measurement: Measure the water flow velocity and direction under different water levels, seasons, and tidal conditions, analyze the spatiotemporal variation of water flow, and determine the scouring effect and stability impact of water flow on the modular unit structure; Water quality testing: Testing water quality indicators such as pH, salinity, dissolved oxygen, chemical oxygen demand (COD), ammonia nitrogen, and total phosphorus to assess the degree of water pollution and its corrosiveness to engineering materials, and to select appropriate engineering materials and protective measures.

[0043] II. Module Quantity Calculation (1) Calculation of bottom area Regular areas: If the underwater shape of the area covered by the project is relatively regular, such as rectangular, circular, or sector-shaped, the underwater area can be calculated directly using geometric formulas. For example, the area of ​​a rectangular area is length multiplied by width; the area of ​​a circular area is π multiplied by the square of the radius; and the area of ​​a sector-shaped area is π multiplied by the square of the radius and then multiplied by the ratio of the central angle to 360 degrees.

[0044] For irregular areas: Area calculation is performed using a grid method or topographic map method. The underwater area is divided into several small grids, each with an equal area. The number of grids falling within the project coverage area is counted, and multiplied by the area of ​​a single grid to obtain the total underwater area. Alternatively, the area of ​​the project coverage area can be directly measured on an underwater topographic map using a planimeter or digitization software.

[0045] (2) Module layout design Single-layer layout: Based on engineering design requirements and underwater topography, determine the single-layer layout scheme of the modules. If the underwater slope is small and the terrain is flat, use a uniformly distributed square or rectangular grid layout; if the underwater slope is large or there are terrain changes such as gullies, adjust the spacing and arrangement direction of the modules to adapt to the terrain undulations and ensure the stability and coverage effect of the modules.

[0046] (3) Calculation of the number of modules Calculation method: Based on detailed water area survey data, accurately calculate the number of modules required for the project, ensure the integrity and functionality of the module unit structure, optimize resource utilization, control project costs, and improve the project's economy and feasibility.

[0047] III. Module Assembly and Connection (1) Cutting of grid strips Cutting preparation: Cut the main keel grid strips and secondary keel grid strips to appropriate lengths according to design requirements.

[0048] (2) Connection of grid strips Slot connection: The main keel grid strip and the secondary keel grid strip are connected and fixed through slots to ensure the firmness and stability of the connection.

[0049] (3) Module assembly (3.1) Connection of edge banding strip Mortise and tenon structure: The edging strip is connected to the fixed main and secondary keel grid strips using a mortise and tenon structure to form a single module. This ensures the tightness and stability of the connection.

[0050] (3.2) Module Connection Snap-fit ​​connection: Modules are connected by fixing slots and ball fixing elements to ensure the flexibility and stability of the overall structure.

[0051] The materials of the main and secondary keel grid strips are selected according to the degree of water pollution in the water area, including: When the water pollution level is mild, the main keel and secondary keel are made of recyclable materials; When the water pollution level is moderate to severe, the main keel and secondary keel are made of pollutant-adsorbing composite materials; When there is a need for ecological restoration in the water area, the surface of the main keel and secondary keel is covered with a biological seed coating layer.

[0052] IV. Equipment Transportation and Deployment (1) Loading the equipment onto the ship Vessel selection: Based on the size, weight, and transportation requirements of the equipment, select a suitable vessel for transportation. The vessel should have sufficient deadweight tonnage and adequate deck space to meet the placement and securing needs of the equipment.

[0053] Ship loading and securing: The assembled device is hoisted to the ship's deck using lifting equipment, and secured to the deck using securing equipment (such as wire ropes, chains, fasteners, wooden blocks, etc.) to ensure stability during transportation.

[0054] (2) Preparation for deployment Target area reconnaissance: Check the hydrological and meteorological conditions of the target area to ensure that the sea conditions and weather conditions are suitable at the time of deployment.

[0055] Positioning system calibration: After the vessel arrives at the target area, the positioning system is used to accurately locate the deployment position. Based on the underwater topographic map of the target area and the deployment requirements of the device, the specific deployment coordinates of the device are determined.

[0056] (3) Device deployment Deployment Operation: After confirming that the deployment location and device status are correct, slowly release the hook of the deployment crane to lower the device to the predetermined underwater position in the target area. During the deployment process, a designated person should be in charge of directing the operation, and the lifting personnel and ship operators should cooperate closely to ensure that the device is deployed smoothly and accurately.

[0057] Deployment monitoring: During the deployment process, pay attention to the sinking speed and attitude changes of the device. If any abnormalities are found, take timely measures to make adjustments.

[0058] V. Post-installation inspection Visual and tactile inspection: In relatively shallow waters, under safe conditions, the installation location, connection status, and fixation status of equipment or devices can be inspected visually or by direct tactile examination to ensure that the installation is secure and not loose.

[0059] Underwater photographic inspection: In complex underwater environments where direct observation by the human eye is difficult, underwater high-definition cameras and imaging sonar can be used to acquire image data of underwater equipment or devices. This inspects the equipment or devices for surface defects such as cracks and corrosion to ensure that the installation meets design requirements.

[0060] ROV (Remotely Operated Vehicle) Inspection: In deep water areas or confined spaces, tethered or untethered underwater robots (ROVs) equipped with high-resolution imaging sonar, underwater cameras, underwater positioning systems, and other equipment can be used. The ROV's camera and sonar equipment can be used to inspect the installation of equipment or devices, including connection status, fixation, and any visible defects.

[0061] Multibeam sonar inspection: Large-area underwater terrain and equipment inspection, using multibeam sonar for full coverage detection, to check whether the equipment is installed correctly.

[0062] VI. Maintenance and Management (1) Regular inspection Structural inspection: Regularly inspect underwater structures, including material properties, geometric dimensions, shape, and stability.

[0063] Environmental impact assessment: Assess the impact of water quality, water depth, water flow, etc. on the structure, and promptly identify and address potential problems.

[0064] Timely evaluation of effectiveness and optimization of application.

[0065] (2) Maintenance measures Repair and reinforcement: For problems found during inspection, timely repair and reinforcement should be carried out, such as reinforcement of module units. Example 1

[0066] Example 1 provides a modular device for in-situ suppression of sediment disturbance in lightly polluted waters (COD=45mg / L, ammonia nitrogen=0.8mg / L), such as... Figure 1 As shown, it includes: main keel grid strip 1, secondary keel grid strip 2, edge banding strip 3, slot 4, tenon 5, telescopic bracket 6, fixed slot 7, spherical fixing element 8, and spring 9.

[0067] In Example 1, the main and secondary keel grid strips are made of polypropylene (PP), with a smooth surface. The main keel grid strip 1 and the secondary keel grid strip 2 are connected and fixed through slots 4. The main keel grid strip 1 and the secondary keel grid strip 2 are 10 mm thick, 2.5~5 m long, and 20~40 cm high. A slot 4 is provided every 50~100 cm on the secondary keel grid strip 2, and the slot 4 at each assembly node is 10 cm wide, facilitating on-site splicing with the main keel grid strip 1. Tenons 5 are provided at both ends of the secondary keel grid strip, allowing for fixed connection with the edging strip 3. The edging strip 3 is 10 mm thick, 2.5~5 m long, and 20~40 cm high; its thickness, length, and height can be adjusted according to the actual application scenario. The edging strip 3 is connected and fixed to the main and secondary keel grid strips through mortise and tenon structures. The edging strip 3 enhances the strength of the module unit edges, preventing edge deformation or damage, and also facilitates the splicing between module units. Figure 2 As shown, the main keel grid strip 1 is vertically arranged and serves as the main load-bearing component of the module unit. It is responsible for bearing the vertical load and part of the horizontal load of the entire module unit structure. Its cross-sectional dimensions and material strength must meet the load-bearing requirements to ensure the stability of the module unit. The secondary keel grid strip 2 is horizontally fixed on the main keel grid strip 1 and plays the role of connecting and supporting the module unit panel. Through the vertical cross arrangement with the main keel grid strip 1, they together form the basic support frame of the module unit, giving the module unit good structural rigidity and deformation resistance. It can effectively distribute and transfer loads and ensure the safety and reliability of the module unit during use. like Figure 2As shown, the two ends of the left and right edge strips 3 of the module unit are provided with spherical fixing elements 8, and the two ends of the upper and lower edge strips 3 are provided with fixing slots 7. The fixing slots 7 are composed of a pair of oppositely arranged elastic bodies. The elastic bodies are curved into the slots to form an arc-shaped entrance. The diameter of the spherical fixing element 8 matches the width of the arc-shaped entrance after it is opened in the fixing slots 7. The upper half of the spherical fixing element 8 is arc-shaped to facilitate insertion into the arc-shaped entrance. The lower half of the spherical fixing element 8 is groove-shaped and matches the barb at the end of the curved elastic body to prevent the spherical fixing element 8 from slipping out of the fixing slots 7. The spherical fixing element 8 is inserted into the fixing slot 7 of another module unit to form a flexible connection. The elastic body has moderate elasticity, ensuring that the module units can be connected to each other to form a strong mesh structure, while also having a certain degree of flexibility through moderate deformation of the elastic body. When adjacent modules are spliced, the upper hemispherical part of the spherical fixing element 8 slides into the arc-shaped elastic body of the fixing slot 7, compressing the elastic body to produce deformation. When the hemispherical sphere of the spherical fixing element 8 is fully inserted into the slot, the elastic body rebounds, and its barbs match and engage with the groove edge of the lower half of the hemispherical sphere to form a mechanical lock. The spring provides continuous preload, allowing the module to deflect ±5° in the horizontal direction and displacement ±3cm in the vertical direction, thereby adapting to the underwater slope and terrain undulations, while ensuring the stability of the overall structure.

[0068] like Figure 3 As shown in the top view, each individual grid structure module unit is square. These modules are connected to each other via a flexible connection formed by the aforementioned spherical fixing element 8 and fixing slot 7, creating a robust yet flexible mesh structure adaptable to complex terrain at the bottom of rivers and lakes. Figure 4 As shown, the bottom of the module unit is equipped with a retractable support 6 that can be extended and locked. The retractable support 6 is made of 304 stainless steel with a diameter of 12mm. The overall module weight is ≤15kg / m², which is convenient for recycling and reuse. Before deploying the module unit, the length of the retractable support 6 is set according to the actual depth of the river and lake bottom sediment and locked before deployment to ensure that the module is not covered by silt.

[0069] like Figure 5 As shown, Figure 5 for Figure 3 A partially enlarged view of the flexible connection mechanism A. Figure 5 The connection mechanism between the fixing slot 7 and the ball fixing element 8 in Embodiment 1 is shown; The fixed slot 7, as the core connecting component of the modular device in Embodiment 1, adopts an integrated injection molding process. The overall structure includes a fixed slot base 7-1, a slot head 7-3 connected to the fixed slot base 7-1, a slot head sliding hook 7-4 that is curved inward into the slot and connected to the slot head 7-3, and a spring mounting groove is provided near the slot head 7-3. The spring 9 installed in the spring mounting groove provides a continuous clamping force for the slot head 7-3. The fixed slot base 7-1 is made of polyvinyl chloride (PVC) with a thickness of 12mm. It is rigidly installed in the groove at the end of the edge banding strip through a tenon and mortise structure. A spring mounting groove is provided on the outer part of the base near the slot head 7-3. One end of the spring 9 is installed in the spring mounting groove, and the other end abuts against the inner wall of the groove of the edge banding strip to ensure the stability of the spring 9 after installation and to provide continuous clamping force for the slot head 7-3.

[0070] The inner wall 7-2 of the fixed slot adopts an arc-shaped curved surface design, and the radius of curvature matches the radius of curvature of the outer surface of the arc-shaped clamp 8-2 of the ball fixing element 8. The surface is coated with a wear-resistant polytetrafluoroethylene coating with a friction coefficient ≤0.05, which reduces the friction during connection.

[0071] The card slot head 7-3 is composed of a pair of symmetrically arranged arc-shaped elastomers, made of a blend of polypropylene (PP) and thermoplastic polyurethane (TPU), with a Shore hardness of 75±5HA, combining rigidity and elasticity.

[0072] The slot head sliding hook 7-4 is located at the end of the slot head and has an inverted hook-shaped structure that curves inward into the slot. The hook tip angle is 30°-60°. The narrowest part of the pair of symmetrically arranged slot head sliding hooks 7-4 is 5-20mm smaller than the widest part of the ball fixing element 8, while the width of the widest part of the inlet is 1.2 times that of the widest part of the ball fixing element 8. This ensures that the ball fixing element 8 can be smoothly inserted into the fixing slot 7, and after insertion, it is rebounded and locked by the narrowest part of the slot head sliding hook 7-4 to prevent slippage.

[0073] The spring 9 is made of 304 stainless steel wire, with an outer diameter of 7mm, a free length of 20mm, and a preload of 5-8N. It is installed in the spring mounting groove of the fixed slot base to provide continuous clamping force for the slot head 7-3.

[0074] The spherical fixing element 8 serves as a connecting and matching component between adjacent modules, cooperating with the fixing slot 7 to achieve a flexible connection. The overall structure includes a snap-fit ​​post 8-1 fixedly installed at the end of the edge banding strip, an arc-shaped snap-fit ​​connector 8-2 connected to the snap-fit ​​post 8-1, and an arc-shaped slot near the snap-fit ​​post 8-1 on the arc-shaped snap-fit ​​connector 8-2. The edge of the arc-shaped slot forms a snap-fit ​​connector sliding hook 8-3. The snap-fit ​​post 8-1 is made of 304 stainless steel, with a diameter of 10mm and a length of 20mm. It is fixed to the edge strip by a threaded connection with a connection strength of ≥5kN to ensure that it will not loosen under the impact of water flow.

[0075] The arc-shaped snap-fit ​​connector 8-2 is located at the top of the snap-fit ​​post. Its surface is hemispherical, and its diameter is consistent with the radius of curvature of the inner wall of the fixed snap-fit ​​groove. The width ratio between the widest part of the arc-shaped snap-fit ​​connector 8-2 and the widest part of the opening of the fixed snap-fit ​​groove is 1:1.2, which ensures that the arc-shaped snap-fit ​​connector 8-2 can be smoothly inserted into the fixed snap-fit ​​groove 7. The groove structure in the lower half complements and locks with the barb structure of the fixed snap-fit ​​groove 7, ensuring that it will not slip off after snapping.

[0076] The sliding hook 8-3 of the snap-fit ​​connector is located at the lower part of the arc-shaped snap-fit ​​connector and has an inverted groove structure. Its angle is complementary to that of the sliding hook 7-4 of the snap-fit ​​head. When the ball fixing element 8 is fully inserted into the fixing slot 7, the two sliding hooks interlock with each other to form a mechanical lock and prevent the connection from coming off.

[0077] Example 1 also provides a method for using a modular device for in-situ suppression of disturbance of river and lake bottom sediments, such as... Figure 6 As shown, it includes the following steps: I. Survey of water area and underwater topography This includes: determining the survey scope, investigating water level changes, measuring bottom sediment thickness, measuring water flow and water quality indicators; clarifying the geographical coordinates of the surveyed water area, including the boundary coordinates in the four directions of east, south, west, and north, and the total area of ​​the water area. The survey scope is determined using geographical coordinate mapping, with boundary coordinate accuracy of ±0.01° and area calculation error ≤2%; investigating water level changes in the water area, including the annual average water level, highest water level, lowest water level, and the period and amplitude of water level changes. The water level changes are monitored in real time using a pressure level gauge, with a monitoring frequency of once per hour, and compared with historical hydrological data for at least one year to obtain the annual average water level, highest water level, and lowest water level; and utilizing multibeam echo sounders and singlebeam echo sounders. Equipment such as side-scan sonar is used to perform high-precision mapping of underwater topography, acquiring three-dimensional data of the underwater topography, including information on bottom undulations, gullies, and slopes, and drawing detailed underwater topographic maps. The thickness of river and lake bottom sediment is measured by combining high-precision echo sounding with sediment sampling to draw bottom sediment isopyrographs, where: the sounding resolution is ≤ ±2cm, and the sediment sampling point density is ≥ 1 point / 100m². The bottom sediment thickness data is used to determine the length of the telescopic support to ensure that the distance between the bottom of the module and the bottom sediment surface is ≥ 10cm. The water flow velocity and direction are measured under different water levels, seasons, and tidal conditions to analyze the spatiotemporal variation of water flow and determine the scouring effect and stability impact of water flow on the module unit structure. The water flow measurement was performed using an acoustic Doppler current profiler (ADCP) with vertical stratification. Specific parameters included: flow velocity measurement range of 0.01~5 m / s, flow direction accuracy of ±3°, and vertical stratification thickness of 0.5 m. The spatiotemporal variation patterns of water flow during the high-water season, low-water season, and normal-water season were obtained to assess the scouring effect of water flow on the grid structure.

[0078] The system measures water quality indicators such as pH, salinity, dissolved oxygen, chemical oxygen demand (COD), ammonia nitrogen, and total phosphorus to assess the degree of water pollution and its corrosiveness to engineering materials, and to select appropriate engineering materials and protective measures.

[0079] II. Calculate the required number of modules Based on detailed water area survey data, the number of modules required for the project is accurately calculated to ensure the integrity and functionality of the module unit structure. Simultaneously, resource utilization is optimized, project costs are controlled, and the economic efficiency and feasibility of the project are improved. If the underwater shape of the project coverage area is relatively regular, such as rectangular, circular, or sector-shaped, the underwater area can be directly calculated using geometric formulas. For example, the area of ​​a rectangular area is length multiplied by its width; the area of ​​a circular area is π multiplied by the square of its radius; and the area of ​​a sector-shaped area is π multiplied by the square of its radius and then multiplied by the ratio of the central angle to 360 degrees. For irregularly shaped underwater areas, the area can be calculated using a grid method or topographic map method. The underwater area is divided into several small grids, each with an equal area. The number of grids falling within the project coverage area is counted, and multiplied by the area of ​​a single grid to obtain the total underwater area. Alternatively, the area of ​​the project coverage area can be directly measured on an underwater topographic map using a planimeter or digitization software, employing a 1m×1m grid method with a grid coverage rate ≥95% or a CAD planimeter with an area fitting error ≤2%. Based on the engineering design requirements and underwater topographic conditions, the single-layer layout scheme of the modules is determined. If the underwater slope is small and the terrain is flat, a uniformly distributed square or rectangular grid layout can be used. If the underwater slope is large or there are terrain variations such as gullies, the spacing and arrangement direction of the modules need to be adjusted. When the underwater slope is ≤15°, a uniform square layout is used with a module spacing of 0.5-1m. When the slope is >15°, the module spacing is increased by 20% and arranged along the contour lines to adapt to the terrain undulations and ensure the stability and coverage effect of the modules.

[0080] III. Module Assembly and Connection The main / secondary keel is connected by the slot 4, the edge strip 3 is encapsulated by the tenon and mortise structure, and adjacent modules are flexibly spliced ​​with the spherical fixing element 8 through the fixing slot 7; (1) Cut the main keel grid strip and the secondary keel grid strip to a suitable length.

[0081] (2) Connect and fix the main keel grid strip and the secondary keel grid strip through the slot.

[0082] (3) Connect the edge banding strip to the fixed main and secondary keel grid strips through mortise and tenon structure to form a single module.

[0083] (4) The modules are flexibly connected to each other through the fixed slot 7 and the ball fixing element 8.

[0084] IV. Transportation and Placement (1) Adjust the height of the telescopic support 6 according to the thickness of the river and lake bottom sediment in the previous exploration.

[0085] (2) Transport the assembled device to the target area by ship and deploy it. Select a suitable vessel for transportation based on the size, weight, and transportation requirements of the device. The vessel should be selected based on a safety factor of 1.5 times the total weight of the modules, with a deck load capacity ≥3t / m² and a crane lifting capacity ≥20t, to meet the placement and fixing requirements of the device. Check the hydrological and meteorological conditions of the target area to ensure that the sea conditions and weather conditions are suitable at the time of deployment. After the vessel arrives at the target area, use DGPS + UBS (Ultra-Short Baseline) joint positioning, with a horizontal positioning error ≤0.5m, a deployment speed controlled at 0.2~0.3m / s, and an inclination angle ≤10° to accurately locate the deployment position. Determine the specific deployment coordinates of the device based on the underwater topographic map of the target area and the deployment requirements of the device. After confirming that the deployment position and device status are correct, slowly release the hook of the deployment crane and deploy the device to the predetermined underwater position in the target area. During the deployment process, a dedicated person should be in charge of command, and the hoisting personnel and the ship's driver should cooperate closely to ensure that the device is deployed smoothly and accurately. During the deployment of the device, pay close attention to its sinking speed and attitude changes. If any abnormalities occur, take timely measures to adjust it.

[0086] V. Post-installation inspection The installation quality of the equipment is assessed using visual inspection, underwater photography, ROV, or multibeam sonar; including: Shallow water area inspection: Confirm the secure connection of the device by visual inspection or touch, ensuring there is no loosening or displacement; Deep water inspection: Using an ROV equipped with a 2-megapixel camera (illumination intensity ≥5000 lux) or multi-beam sonar (point cloud density ≥5 pts / m²), the surface defects (such as cracks, corrosion) and coverage integrity of the equipment are detected.

[0087] VI. Maintenance and Management: Regularly inspect the structural integrity and environmental impact, repair and reinforce damaged components, and assess the impact of water flow on the equipment annually; include: Regular inspections: Structural stability is checked quarterly using underwater photography or ROV, and the impact of water flow erosion on module spacing is assessed annually; Repair and reinforcement: Reinforce deformed grid strips, and re-press or replace loose connection nodes with retaining rings.

[0088] After three months of application of the device in Example 1 in a flat water area (slope ≤15°), the concentration of suspended solids in the water decreased by 45%~60%, and the transparency increased by 30%~40%. The grid structure achieved a sediment fixation rate of over 85%, effectively blocking the diffusion of bottom sediment caused by wind-driven currents and ship disturbances. A team of five can complete the assembly and deployment of 1200m² modules per day, shortening the construction cycle by 50% compared to traditional in-situ covering technology. The total cost of materials and construction is approximately 150~200 yuan / m², only one-quarter of that of ecological dredging technology. In areas with a bottom sediment thickness difference of 0~30cm, the telescopic support ensures that the distance between the bottom of the module and the bottom sediment surface is ≥10cm, without settlement or tilting. The flexible connection allows the module to maintain the integrity of the overall structure even when the water level fluctuates by ±50cm. This verifies the feasibility and advantages of the present invention. Example 2

[0089] Example 2 provides a modular device and method for in-situ suppression of disturbance of river and lake bottom sediments for complex terrain and water areas. Unlike Example 1, Example 2 adopts a flexible connection device of "male module + female module". Example 2 provides a modular device for in-situ suppression of disturbance in river and lake bottom sediments. Targeting complex water areas with slopes of 15°~25° and gullies of 0.5~1.2m depth, it adopts a binary structure design of "male module + female module," achieving flexible splicing through modular disassembly. The male module is a module unit with only a spherical fixing element 8, and the female module is a module unit with only a fixing slot 7. The male and female modules are arranged alternately in a 1:1 ratio, forming a mesh structure. The dimensions of a single module are 1m × 1m × 30cm (length × width × height). The common module is an active connection unit, and its core components include main keel grid strips, secondary keel grid strips, edge banding strips, spherical fixing elements, and telescopic brackets. The main keel grid strips are made of polystyrene-acrylate copolymer (PSAC), with a length of 1m, thickness of 10mm, and height of 30cm. A 10cm wide slot is provided every 50cm along the length for connection with the secondary keel. The secondary keel grid strips are made of polypropylene (PP), with the same dimensions as the main keel. They intersect the main keel perpendicularly through slots to form 50cm×50cm grid units, with a node shear strength ≥5kN. The edge banding strips are made of polyvinyl chloride (PVC) and are fixed to the main / secondary keel using a tenon and mortise structure, with a fit clearance ≤0.2mm. Each of the four corners has an 8cm diameter connection hole.

[0090] The spherical fixing element 8 is the core connecting component, with 4 elements per module, distributed at the four corners of the edge strip. It is made of 316 stainless steel core coated with polyoxymethylene (POM), with a diameter of 5cm, a height of 8cm, and an exposed length of 3cm. The lower half of the element has an inverted conical hook structure with a cone angle of 75° and a hook depth of 8mm, forming a complementary locking with the fixing groove of the mother module. The telescopic bracket is a 316 stainless steel double-tube structure, including an inner tube with a diameter of 12mm and an outer tube with a diameter of 16mm. It has a retracted length of 30cm and a maximum extension of 150cm. The bottom has 5mm high anti-slip teeth, a locking force ≥10kN, and a 40% improvement in adhesion to the bottom mud compared to traditional structures.

[0091] The mother module is a passive connection unit. Its main structure includes a main keel, a secondary keel, an edge band, and a telescopic bracket, which is completely identical to the male module, except that the spherical fixing elements at the four corners are replaced with fixing slots 7. The fixing slots are made of nylon 6 (PA6) and have built-in galvanized steel wire springs (1mm in diameter, 6N preload). The opening width is 6cm and the depth is 10cm. A pair of arc-shaped elastic bodies (3mm thick) are symmetrically arranged on the inner side. The ends of the elastic bodies are bent into the slots to form barbs (8mm deep). After engaging with the inverted conical barbs of the spherical elements of the male module, the pull-out force of a single node is ≥8kN and the shear force is ≥5kN.

[0092] The male and female modules are quickly joined using a "spherical element-fixed slot": after the spherical element of the male module is aligned with the slot entrance of the female module, an axial pressure of ≥50N is applied, causing the sphere to compress the elastic body and deform; when the sphere is fully inserted into the slot, the elastic body rebounds, and the hook structure interlocks to form a flexible connection node. A single node allows adjacent modules to deflect ±12° in the horizontal direction and generate ±3cm of relative displacement in the vertical direction, which can adapt to 25° steep slopes and 10cm wide gullies. The overall structural flexibility is 25% higher than that of traditional single modules.

[0093] Example 2 provides a method of using the modular device, such as... Figure 5 As shown, it includes the following steps: I. Water area survey and topographic mapping A multibeam echo sounder (120° beam coverage angle, ±2cm depth resolution) combined with side-scan sonar (200kHz frequency) was used to map a 5000m² water area. The geographic coordinate accuracy was ±0.01°, and the point cloud density was ≥8pts / m². A 1:500 topographic map was generated, identifying three gully areas with a depth >1m. Water level monitoring was performed using a pressure-type water level gauge, collecting data hourly. Combined with one year of historical hydrological data, the annual average water level was determined to be 1.8m, and the water level fluctuation was 1.2m. The sediment thickness was obtained through a combination of high-precision echo sounding and sediment sampling (sampling point density 1 / 100m²), and isopyrographs were generated. These were used to adjust the length of the telescopic support to ensure that the distance between the bottom of the module and the sediment surface was ≥10cm. The flow measurement adopts ADCP vertical layer measurement (layer thickness 0.5m), with a flow velocity range of 0.01~5m / s and a flow direction accuracy of ±3°, to obtain the flow pattern during the wet / dry / normal water periods and assess the risk of scour.

[0094] II. Module Quantity Calculation and Layout The effective water area is calculated to be 4800 m² using a 1m × 1m grid method (excluding 200 m² of gullies where paving is not possible). Each module covers 1 m². Using the formula "Total quantity = Effective underwater area / Single module area × 1.1 (redundancy coefficient)," a total of 2640 public modules and 2640 parent modules are required, for a total of 5280 modules. In the layout design, the module spacing is 0.5m in flat areas (slope < 15°) and 0.4m in steep slope areas (15°~25°), arranged along contour lines to ensure a module conformity to the terrain ≥ 95%.

[0095] III. Grating bar processing and module assembly The main and secondary keel grid strips are laser-cut with a length tolerance of ±1mm and an end face perpendicularity of ≤0.5°. The slot connections are assembled using a hydraulic crimping machine with a crimping force ≥5kN. During male module assembly, the spherical fixing element is secured to the four corners of the edging strip using M8 bolts (bolt embedment depth 20mm); the female module is fitted with a fixing slot, ensuring the slot opening is flush with the end face of the edging strip. For mortise and tenon structure assembly, the tenons are coated with epoxy resin and hammered into place, with a curing time ≥24h (at 25℃) to ensure connection strength.

[0096] IV. Transportation and Placement Select vessels with a deck load capacity ≥3t / m² and a lifting capacity ≥20t. Load the modules according to a safety factor of 1.5 times the total module weight. Use cross-linked steel wire ropes (angle 45°±5°) and anti-slip wooden pads for fixation. The allowable displacement during transportation is ≤10cm. Deployment uses DGPS + Ultra-Short Baseline (USBL) combined positioning, with a horizontal positioning error ≤0.5m. The deployment speed is controlled at 0.2~0.3m / s, and the tilt angle ≤10°. When deploying in trench areas, adjust the telescopic support to 120cm, and embed the bottom anti-slip teeth into the bottom mud to ensure module stability.

[0097] V. Post-installation inspection After deployment, an ROV equipped with a 2-megapixel camera was used for underwater inspection with an illumination intensity of ≥5000 lux. The inspection focused on the locking status of the connection nodes and the tilt of the modules (≤8°). A multi-beam sonar full-coverage scan (overlap rate 25%) was performed to confirm that the device coverage was 100%.

[0098] VI. Maintenance and Management The structural integrity is checked quarterly using ROV, and the impact of water flow scouring is assessed annually (flow velocity change ≤ 0.5 m / s). Loose joints are re-pressed, and damaged modules are replaced with male and female pairs to ensure long-term stable operation.

[0099] After 6 months of application in a typical complex terrain water area, the device of Example 2 showed a sediment resuspension inhibition rate of 55%, a 42% reduction in suspended solids concentration in the water, no loosening of module connection nodes, and an overall structure that adapts to 25° steep slopes and 10cm wide gullies. The construction efficiency was improved by 30% compared to traditional methods (150m² installation per person per day), verifying the feasibility and advantages of the present invention. Example 3

[0100] Example 3 proposes a modular device and its application method for in-situ suppression of sediment disturbance in rivers and lakes in moderately polluted waters (COD=80mg / L, ammonia nitrogen=2.5mg / L). The difference from Example 1 is that: In Example 3, the main and secondary keels are made of activated carbon-polypropylene composite material (activated carbon accounts for 20% of the mass), formed by injection molding. The surface has a honeycomb porosity of 25%, a thickness of 12 mm, a length of 2.5 m, and a height of 30 cm. The activated carbon particles are uniformly dispersed in the PP substrate, and a glass fiber reinforcement layer (2 mm thick) is added at the card slot connection to ensure a connection strength ≥8 kN. Example 4

[0101] Example 4 proposes a modular device and its application method for in-situ suppression of river and lake bottom sediment disturbance in waters requiring ecological restoration (submerged plant coverage <10%). The difference from Example 1 is that: In Example 4, regarding material selection, the main and secondary keels are made of polystyrene-acrylate copolymer (PSAC), with a biological seed layer covering the surface (inner layer PLA sponge thickness 3mm, outer layer of Vallisneria natans seed density 80 seeds / cm² + Bacillus subtilis inoculant 1×10⁻⁶). 8 (CFU / g), thickness 15mm, length 2m, height 35cm.

[0102] The coating layer is fixed to the keel with a water-based adhesive (environmentally friendly polyurethane), and the seed layer is covered with a biodegradable non-woven fabric (0.1 mm thick) to ensure that the seeds do not fall off before germination.

[0103] The above description of the embodiments is provided to enable those skilled in the art to understand and use the present invention. It will be apparent to those skilled in the art that various modifications can be easily made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention are within the protection scope of the present invention.

Claims

1. A modular device for in-situ suppression of disturbance of river and lake bottom sediments, characterized in that, include: Grid Structural module: It is formed by the main keel grid strip and the secondary keel grid strip being connected by slots, and the outer edge is sealed by the edge banding strip; Flexible connection mechanism: includes a fixing slot and a ball fixing element. The fixing slot is located at the end of the edge banding strip and is composed of a pair of arc-shaped elastic bodies with barbs. The elastic bodies have built-in springs. The ball fixing element is located at the end of the edge banding strip corresponding to the fixing slot position of the adjacent module. After matching and engaging with the fixing slot of the adjacent module, it forms a deflectable flexible connection mechanism. The grid structure modules are interlocked by a flexible connection mechanism to form a mesh modular device that can adapt to the complex terrain at the bottom of rivers and lakes. The bottom of the grid structure module is equipped with a retractable support to adapt to different sediment thicknesses. By physically fixing the sediment and reducing water flow disturbance, it effectively inhibits the resuspension of river and lake sediment.

2. The modular device for in-situ suppression of river and lake bottom sediment disturbance according to claim 1, characterized in that, The radius of curvature of the arc-shaped elastic body of the fixed slot is 5~10cm, the barb depth is 5mm, the spring preload is 5~8N, and after engaging with the ball fixing element, it allows the adjacent module to deflect horizontally by ±5° and vertically by ±3cm.

3. The modular device for in-situ suppression of river and lake bottom sediment disturbance according to claim 1, characterized in that, The width ratio between the widest part of the sphere fixing element and the widest part of the fixing slot opening is 1:1.

2. The lower half of the sphere fixing element is provided with a chamfer, and the edge of the chamfer is complementary and locked with the barb structure of the fixing slot to prevent slippage after locking.

4. The modular device for in-situ suppression of river and lake bottom sediment disturbance according to claim 1, characterized in that, The length of the telescopic bracket is adjustable, with an adjustment range of 0~50cm, and it is fixed by a locking mechanism with a locking strength ≥500N.

5. The modular device for in-situ suppression of river and lake bottom sediment disturbance according to claim 4, characterized in that, The telescopic bracket includes an inner rod and an outer tube, and its length is adjusted by a pin hole and a spring pin.

6. The modular device for in-situ suppression of river and lake bottom sediment disturbance according to claim 1, characterized in that, The main keel, secondary keel, and edge strip are made of polyvinyl chloride (PVC) or polypropylene (PP), with a thickness of 10mm, a length of 2.5~5m, and a height of 20~40cm.

7. A method for using the modular device for in-situ suppression of disturbance of river and lake bottom sediments as described in any one of claims 1-6, characterized in that, Includes the following steps: S1. Water area survey and topographic mapping: Determine the survey scope, investigate water level changes, measure bottom sediment thickness, measure water flow and water quality indicators; S2. Module Quantity Calculation: Based on the underwater area and the coverage area of ​​a single module, the quantity is calculated using the formula "Module Quantity = Underwater Area / Single Module Area × Redundancy Coefficient"; S3. Module assembly and splicing: The main / secondary keel is connected by slots, the edge strip is encapsulated by mortise and tenon structure, and adjacent modules are flexibly spliced ​​with the spherical fixing element through the fixing slot; S4. Transportation and Deployment: Adjust the length of the telescopic support according to the thickness of the bottom sediment, select a suitable ship transportation device, and deploy the module to the target water area through the positioning system, controlling the deployment speed and attitude; S5. Post-installation inspection: Use visual inspection, underwater photography, ROV or multibeam sonar to check the installation quality; S6. Maintenance and Management: Regularly inspect the structural integrity and environmental impact, repair and reinforce damaged parts, and assess the impact of water flow on the device annually.

8. The method for using a modular device for in-situ suppression of river and lake bottom sediment disturbance according to claim 7, characterized in that, The sediment thickness measurement in step S1 adopts a combination of high-precision echo sounding and sediment sampling, with a sounding resolution of ≤ ±2cm and a sampling point density of ≥ 1 point / 100m². The data is used to determine the length of the telescopic support to ensure that the distance between the bottom of the module and the sediment surface is ≥ 10cm.

9. The method for using a modular device for in-situ suppression of river and lake bottom sediment disturbance according to claim 7, characterized in that, The materials of the main and secondary keel grid strips mentioned in step S3 are selected according to the degree of water pollution: recyclable materials are used for light pollution, pollutant adsorption composite materials are used for moderate to heavy pollution, and biological seed layers are coated when ecological restoration is required.

10. The method for using a modular device for in-situ suppression of river and lake bottom sediment disturbance according to claim 7, characterized in that, The deployment and positioning described in step S4 adopts DGPS + UBS (Ultra-Short Baseline) joint positioning, with a horizontal error ≤0.5m, a deployment speed of 0.2~0.3m / s, and a tilt angle ≤10°.

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