In-situ reverse dredging and restoration method for both sides of the river based on the natural scour line

Abstract

The present invention provides a reverse dredging and repair method for both sides of a river channel in situ based on a natural scouring line, comprising the following steps: dividing the river channel to be dredged into a number of dredged areas along the flow direction, and taking the most downstream dredged area as the first working area; obtaining the historical scouring line, overflow scouring line, floodplain scouring line and safety scouring line of the area to be dredged, and defining the original basin, overflow area, floodplain area and safety area; calculating the silt storage volume of the original basin, overflow area and floodplain area; taking the safety area as the reverse silt storage area, and calculating the silt holding volume; pumping all the silt from the original basin, overflow area and floodplain area to the reverse silt storage area; then going upstream to the next area to be dredged, completing the above steps until the source. The present invention reverses upstream to restore the disease to the repair level under natural bearing conditions, restore the balance of the ecological natural environment, and harmlessly treat the scouring and silting problem.

Description

Technical Field

[0001] The present invention belongs to the field of river dredging, and in particular relates to a reverse dredging method based on natural scour lines, which conducts ecological restoration from the downstream upstream and performs scour restoration on both sides of the original site. It is suitable for siltation areas formed by dynamic basins, and the impact range involves scour restoration of rivers, lakes, reservoirs, large rivers and coastlines. Background Art

[0002] In the dynamic watershed, both the existing ecological watershed and the artificially constructed reservoir watershed have experienced a reduction in reservoir capacity due to the inclusion of sand and mud during the natural sedimentation process. The historical scour line has undergone natural displacement, and the accumulation has increased and deepened the disasters caused by hidden dangers. Especially when the rainy season comes, urban waterlogging, reduced reservoir capacity, soaring water levels, and dike and dam breaches are very serious, which can easily cause casualties and property losses. The main reason is that the river channel is raised by silt, which reduces the river's capacity.

[0003] The silt accumulation in the historical scour line, overflow scour line and floodplain scour line in the river channel is very serious, and dredging is needed to increase the river's carrying capacity.

[0004] The existing dredging work involves transporting the silt to other places for landfill disposal, which is costly and has little effect on the long-term planning of river safety.

[0005] The current dredging methods are mainly:

[0006] 1. Scouring and silting method: flush the silt at the target point, transfer it to the downstream or other areas, then collect it centrally and backfill it to the pre-set storage point.

[0007] 2. Excavation and drainage method: cut the desilting point, drain the water, dig out the sediment, and transport it to the backfill point.

[0008] 3. Filter press method: The sludge is filtered through the equipment to remove the water, filter it into mud cake, and then landfill it.

[0009] The disadvantages are: it is necessary to select landfill sites of equal volume in advance, the cost of land acquisition is high, there are few suitable geographical locations, and it is easy to cause environmental pollution to the downstream during and after the landfill. If improper storage causes a dam break, it will cause impact and damage to the downstream. Summary of the invention

[0010] An object of the present invention is to provide a method for in-situ reverse dredging and repairing both sides of a river channel based on a natural scour line, and to provide at least the advantages to be described later.

[0011] Another object of the present invention is to provide a reverse dredging and repair method for both sides of the river channel based on the natural scour line, which adopts the concept of silt on both sides of the natural scour line and upstream for nearby treatment, so as to achieve the dual purpose of silt utilization on site, discharge at the original point of soil erosion for treatment, and improve the natural environment, and form a comprehensive environmental protection ecological system with water-based ecological organization reorganization and underwater masonry structure protection of embankments. Through the measurement and design calculation of the reservoir capacity database and the completion of the big data acquisition system, the comprehensive linear model is converted into a three-dimensional governance entity.

[0012] The technical solution of the present invention is as follows:

[0013] The reverse dredging and restoration method for both sides of the river channel in situ based on the natural scour line includes the following steps:

[0014] Divide the river channel to be desilted into several desilting areas along the flow direction, and take the most downstream desilting area as the first work area;

[0015] Obtain the historical scouring line A, overflow scouring line B, floodplain scouring line C and safety scouring line D of the area to be desilted, and define the original watershed, overflow area, floodplain area and safety area;

[0016] Calculate the silt storage volume Q of the original basin, spillway area and floodplain area 原 , Q 溢 and Q 漫 ;

[0017] The safe area is used as the reverse sludge storage area, and the sludge holding volume Q is calculated 容 ;

[0018] When Q 容 Greater than or equal to Q 原 +Q 溢 +Q 漫 When Q 容 Less than Q 原 +Q 溢 +Q 漫 When the original area is higher than the spillway area, and the spillway area is higher than the floodplain area, the silt in the original basin, the spillway area and the floodplain area will be pumped out to the reverse silt storage area, and the excess silt will be stored in the external silt storage area;

[0019] Then go upstream to the next area to be dredged and complete the above steps until you reach the source.

[0020] Preferably, in the in-situ reverse dredging and repair method on both sides of the river channel based on the natural scour line,

[0021] Get the original average width of the watershed b原 , average silt depth h 原 and perimeter l 原 , the original basin silt storage volume Q is calculated 原 , Q 原 =b 原 xh 原 x 原 ;

[0022] Get the average width b of the spillway basin 溢 , average silt depth h 溢 and perimeter l 溢 , the silt storage volume Q in the overflow basin is calculated 溢 , Q 溢 =b 溢 xh 溢 x 溢 ;

[0023] Get the average width b of the floodplain basin 漫 , average silt depth h 漫 and perimeter l 漫 , the silt storage volume Q in the floodplain basin is calculated 漫 , Q 漫 =b 原 xh 漫 x 漫 .

[0024] Preferably, in the reverse dredging and repair method for the in-situ both sides of the river channel based on the natural scour line, the average width b of the safe watershed is obtained. 安 , average silt depth h 淤安 , average depth h 安 and perimeter l 安 , calculate the sludge holding volume Q 容 , Q 容 =b 安 xh 安 x 安 .

[0025] The present invention has the following beneficial effects:

[0026] (1) The reverse silt discharge area is a silt storage point, which does not require long-distance transportation and can be processed on site;

[0027] (2) It can restore the disaster to the level of restoration under natural conditions, restore the balance of the ecological environment over a longer period of time, and harmlessly deal with erosion and siltation problems.

[0028] Other advantages, objectives and features of the present invention will be embodied in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic diagram of river channel area division in an embodiment of the in-situ reverse dredging and restoration method for both sides of a river channel based on the natural scour line provided by the present invention. Detailed implementation manners

[0030] The following further elaborates on the present invention in conjunction with the accompanying drawings, enabling those skilled in the art to implement it with reference to the text of the specification.

[0031] It should be understood that terms such as "having", "including", and "comprising" used herein do not preclude the presence or addition of one or more other elements or combinations thereof.

[0032] First, conduct research on the hydrodynamic mathematical model of typical sections of the water conveyance project

[0033] (1) Based on the basic theoretical principles of non-linear river dynamics, starting from the vector form of the water flow continuity equation and the motion equation, the control equation of water flow motion in the curvilinear coordinate system was established. The center line of the bend was generalized and described, and the first-order perturbation equation was established. The research area was investigated, and corresponding constitutive relations were constructed according to the different physical properties of river sediment.

[0034] (2) The motion state of sediment particles is mainly determined by the relative velocity. When u = 0 and up = ut, the fluid is stationary and the particles move downward. When up = 0 and u = ut, the soil particles are suspended. When u > ut and up > 0, the soil particles move upward. When u < ut and up < 0, the fluid is stationary and the soil particles move downward. In this study, the river flow velocity conditions in the research area were classified, and the incipient motion conditions of sediment under different flow velocity conditions were calculated.

[0035] (3) After the sediment starts to move, analyze the motion states of bed load and suspended load in the river, and analyze the river bed surface and the sediment-carrying capacity of the river.

[0036] (4) Use indoor experiments to verify the theoretical analysis results of the research area and conduct practical verification in combination with the measured data of the research area over the years.

[0037] Difficulty: Establish the non-steady flow control equation and the two-dimensional hydrodynamic numerical model, and determine the internal and external boundary conditions.

[0038] Innovations and difficulties

[0039] Establishment of a three-dimensional sediment motion mathematical model.

[0040] Based on the basic theoretical principles of non-linear river dynamics, starting from the vector form of the water flow continuity equation and the motion equation, considering the factors of water, sand, and soil, the control equation of water flow motion in the curvilinear coordinate system was established.

[0041] like Figure 1 As shown, the present invention provides a method for reverse dredging and repairing both sides of a river channel in situ based on a natural scouring line, which comprises the following steps:

[0042] Divide the river channel to be desilted into several desilting areas along the flow direction, and take the most downstream desilting area as the first work area;

[0043] Obtain the historical scouring line A, overflow scouring line B, floodplain scouring line C and safety scouring line D of the area to be desilted, and define the original watershed, overflow area, floodplain area and safety area;

[0044] Calculate the silt storage volume Q of the original basin, spillway area and floodplain area 原 , Q 溢 and Q 漫 ;

[0045] The safe area is used as the reverse sludge storage area, and the sludge holding volume Q is calculated 容 ;

[0046] When Q 容 Greater than or equal to Q 原 +Q 溢 +Q 漫 When Q 容 Less than Q 原 +Q 溢 +Q 漫 When the original area is higher than the spillway area, and the spillway area is higher than the floodplain area, the silt in the original basin, the spillway area and the floodplain area will be pumped out to the reverse silt storage area, and the excess silt will be stored in the external silt storage area;

[0047] Then go upstream to the next area to be dredged and complete the above steps until you reach the source.

[0048] In one embodiment of the in-situ reverse dredging and repair method for both sides of a river channel based on a natural scour line provided by the present invention,

[0049] Get the original average width of the watershed b 原 , average silt depth h 原 and perimeter l 原 , the original basin silt storage volume Q is calculated 原 ;

[0050] Get the average width b of the spillway basin 溢 , average silt depth h 溢 and perimeter l 溢 , the silt storage volume Q in the overflow basin is calculated 溢 ;

[0051] Get the average width b of the floodplain basin 漫 , average silt depth h 漫 and perimeter l 漫 , the silt storage volume Q in the floodplain basin is calculated 漫 .

[0052] In one embodiment of the in-situ reverse dredging and repair method for both sides of a river channel based on a natural scour line provided by the present invention, the average width b of the safe watershed is obtained. 安 , average silt depth h 淤安 , average depth h 安 and perimeter l 安 , calculate the sludge holding volume Q 容 .

[0053] (1) Establish the governing equations of water flow in a curvilinear coordinate system. A generalized description of the centerline of the bend was made, and a first-order perturbation equation was established. A survey was conducted in the study area, and the corresponding constitutive relationship was constructed according to the different physical properties of river sediment. (2) This study classified the flow velocity of rivers in the study area and calculated the starting conditions of sediment under different flow velocities.

[0054] (3) Analyze the riverbed surface and the sediment-carrying capacity of the river.

[0055] (4) The theoretical analysis results of the study area are verified by indoor experiments and combined with the measured data of the study area in previous years for actual verification.

[0056] The present invention provides a method for reverse dredging and repairing both sides of a river channel in situ based on a natural scouring line:

[0057] 1. The reservoir capacity estimation model and calculation method for big data ecological restoration have been formed in actual construction.

[0058] 2. During the formula verification process, the restoration of the Fenhe River Basin was used as a background and became a case in actual construction.

[0059] 3. Derivation, application and ecological restoration are dynamic processes, and specific environmental changes affect the establishment and use of digital models.

[0060] 4. It is verified in the use of examples that the calculation theory and formula are constantly being revised. The establishment of a big data system for reservoir capacity is a long-term dynamic process. The innovation of this patent is the innovation of theory guiding practice, and it proposes a new restoration concept and method. From the technical ideas and calculation formulas, they are based on reality and are methods for sludge ecological treatment.

[0061] The present invention has the following advantages:

[0062] 1. It eliminated the historical land acquisition problem, solved the problem of tight land use indicators, and saved land resources.

[0063] 2. The original scour risk area was structurally reinforced to reduce the scour risk.

[0064] 3. A big data capacity analysis system has been established to intuitively quantify the risk elimination capacity and formulate preventive measures in advance.

[0065] 4. Using a new approach, linear areas throughout the length of the dynamic watershed are characterized as governance points, restoring the historical record to the point of lowest risk.

[0066] 5. It has overturned the historical treatment methods and adopted new treatment methods. While consolidating the embankments and strengthening the slopes, it focuses on ecological greening restoration, making three-dimensional restoration a reality.

[0067] 6. Intuitive parameter model establishment, serialization of basic units, and step-by-step dynamic management have created new calculation methods and verification models.

[0068] The reverse dredging method for a river channel based on in-situ stacking provided by the present invention has a reverse upstream action, which restores the disaster to a repair level under natural bearing conditions, restores the balance of the ecological natural environment, and harmlessly handles the scouring and siltation problems.

[0069] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes, and they can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and the illustrations shown and described herein.

Claims

1. A reverse dredging and repair method for both sides of a river channel based on a natural scouring line, characterized in that: The following steps are involved: Divide the river channel to be desilted into several desilting areas along the flow direction, and take the most downstream desilting area as the first work area; Obtain the historical scouring line A, overflow scouring line B, floodplain scouring line C and safety scouring line D of the area to be desilted, and define the original watershed, overflow area, floodplain area and safety area; Get the original average width of the watershed b 原 , average silt depth h 原 and perimeter l 原 , the original basin silt storage volume Q is calculated 原 , Q 原 =b 原 xh 原 x 原 ; Get the average width b of the spillway basin 溢 , average silt depth h 溢 and perimeter l 溢 , the silt storage volume Q in the overflow basin is calculated 溢 , Q 溢 =b 溢 xh 溢 x 溢 ; Get the average width b of the floodplain basin 漫 , average silt depth h 漫 and perimeter l 漫 , the silt storage volume Q in the floodplain basin is calculated 漫 , Q 漫 =b 原 xh 漫 x 漫； The safe area is used as the reverse silt storage area, and the average width of the safe watershed b is obtained 安 , average silt depth h 淤安 , average depth h 安 and perimeter l 安 , calculate the sludge holding volume Q 容 , Q 容 =b 安 xh 安 x 安 ; When Q 容 Greater than or equal to Q 原 +Q 溢 +Q 漫 When Q 容 Less than Q 原 +Q 溢 +Q 漫 When the original area is higher than the spillway area, and the spillway area is higher than the floodplain area, the silt in the original basin, the spillway area and the floodplain area will be pumped out to the reverse silt storage area, and the excess silt will be stored in the external silt storage area; Then go upstream to the next area to be dredged and complete the above steps until you reach the source.

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