Calculation method for general scour pattern of sea-crossing bridges considering turbulence effect

Abstract

The present invention relates to a calculation method for the general scour pattern of a cross-sea bridge considering the turbulence effect. The research area including the cross-sea bridge project is determined and meshed, the elevations of each grid node are obtained, typical computational hydrological boundary conditions are selected, a non-hydrostatic three-dimensional mathematical model including the entire cross-sea bridge project is established, the hydrodynamic fields before and after the bridge construction are calculated, the tidal level and flow velocity are verified, the pulsating velocity at each grid node, the sediment settlement velocity in still water and the settlement velocity under the influence of turbulent kinetic energy are calculated, the sediment carrying capacity is calculated according to the estuarine fine sediment model, and finally the general scour amplitude of the seabed at each grid node position is calculated, thereby obtaining the characteristics of the general scour amplitude in the upstream and downstream areas of the bridge. Combining the plane three-dimensional numerical model and the sediment carrying capacity calculation method considering the turbulence effect, through the dynamic equilibrium theory, the accurate prediction of the general scour pattern of the cross-sea bridge including the depth and range is realized, and the calculation accuracy of the general scour pattern of the cross-sea bridge is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of bridge scour morphology calculation, and in particular to a general scour morphology calculation method for cross-sea bridges, especially a general scour morphology calculation method for cross-sea bridges considering turbulent effects. Background Art

[0002] Under strong tidal current conditions, the construction of cross-sea bridge projects will constrict the water flow, resulting in an increase in the water flow velocity in a certain area upstream and downstream of the bridge, thus breaking the dynamic equilibrium state of the seabed in the sea area where the bridge is located and causing overall general scour to occur within a certain range upstream and downstream of the bridge. Accurately predicting the general scour morphology of the bridge, such as depth and range, helps to reasonably evaluate the impact of cross-sea bridge projects on the erosion and deposition evolution of the project sea area. Currently, for the general scour calculation of bridges, there are (1) empirical formula methods, including the 64-1, 64-2, and Bodaikov formulas, etc. However, the above formulas are only applicable to waters dominated by bed load transport and can only calculate the depth of general scour. They have large prediction errors in waters dominated by suspended load transport and cannot calculate the general scour range of the bridge. (2) Planar two-dimensional numerical model combined with empirical formula method: Use the planar two-dimensional mathematical model to calculate the velocity changes caused by the bridge before and after the project, and then use the scour and deposition calculation formula proposed by Cao Zude for the tidal current sea area to calculate its general scour morphology. However, this method does not consider the factor of enhanced sediment-carrying capacity caused by the turbulent effect of the bridge. According to the actual observation data of the Hangzhou Bay and Jintang Bridge, its calculation results are generally smaller than the measured values.

[0003] The traditional empirical formula method for general scour depth is not applicable to tidal current sea areas dominated by suspended load transport and can only calculate the maximum general scour depth at the bridge axis position. The planar two-dimensional numerical simulation method combined with the empirical formula method does not consider the influence of the turbulent effect of the water flow caused by the bridge on sediment scour, and the calculation results are generally smaller than the measured values. To address the above problems, the present invention proposes a general scour morphology calculation method for cross-sea bridges considering turbulent effects, which realizes the accurate prediction of the general scour morphology of cross-sea bridges, including depth and range, and improves the calculation accuracy of the general scour morphology of cross-sea bridges.

[0004] The present invention endeavors to solve these and other outstanding needs in the art. Summary of the Invention

[0005] To solve at least one of the technical problems mentioned in the above background art, a general scour morphology calculation method for cross-sea bridges considering turbulent effects is provided. The method combines a planar three-dimensional numerical model and a sediment-carrying capacity calculation method considering turbulent effects, and through the dynamic equilibrium theory, realizes the accurate prediction of the general scour morphology of cross-sea bridges, including depth and range, and improves the calculation accuracy of the general scour morphology of cross-sea bridges.

[0006] In one aspect, the present invention is directed to a method for calculating the general scour pattern of a sea-crossing bridge considering turbulent effects.

[0007] A method for calculating the general scour pattern of a sea-crossing bridge considering turbulent effects is provided, specifically including the following steps:

[0008] Step 1: Determine the research area including the sea-crossing bridge project, perform three-dimensional grid division on the research area, and perform grid encryption division on each pier of the sea-crossing bridge according to the actual shape.

[0009] Step 2: Interpolate the terrain of each node of the three-dimensional grid using the measured terrain data to obtain the elevation of each grid node.

[0010] Step 3: List all boundary conditions within the calculation area, and select typical calculated hydrological boundary conditions according to the measured data.

[0011] Step 4: Establish a non-hydrostatic three-dimensional mathematical model including the entire sea-crossing bridge project, verify the tidal level and flow velocity using the measured data, and obtain the appropriate roughness coefficient value within the research area.

[0012] Step 5: Use the non-hydrostatic three-dimensional mathematical model to calculate the hydrodynamic fields before and after the construction of the sea-crossing bridge; obtain the pre-project planar flow velocity u1, water depth h1, post-project planar flow velocity u2, vertical flow velocity V2, water depth h2, and turbulent kinetic energy k2 at each grid node.

[0013] Step 6: Calculate the pulsating velocity V′2 at each grid node using the relationship between turbulent kinetic energy and pulsating velocity.

[0014] Step 7: Calculate the sediment settling velocity ω in still water at each grid node before bridge construction using the Zhang Ruijin settling velocity formula; then calculate the settling velocity ω under the influence of turbulent kinetic energy at each grid node after bridge construction. t ;

[0015] Step 8: Calculate the sediment-carrying capacity S* according to the estuarine fine-grained sediment model; considering that the flow velocity and water depth at each cross-section position before bridge construction are the same, the sediment-carrying capacity inside and outside the general scour range should also be equal.

[0016] Step 9: Assume that the unit-width discharge at each position remains unchanged during the scour process after bridge construction, and at the same time assume that the settling velocity is basically the same ω under the condition of general scour equilibrium, that is, before the scour after bridge construction develops. ts =ω t , and then the general scour amplitude formula can be obtained, and then calculate the general scour amplitude of the seabed at each grid node position, so as to obtain the general scour amplitude characteristics in the upstream and downstream areas of the bridge.

[0017] In Step 1 of a specific embodiment, the research area including the sea-crossing bridge project is determined according to the water and sediment characteristics of the sea area where the sea-crossing bridge is located.

[0018] In step two of a specific embodiment, for the hydrodynamic calculation before bridge construction, the elevation of the grid nodes at the pier positions adopts the actual terrain data.

[0019] In step two of a specific embodiment, for the hydrodynamic calculation after bridge construction, the grids at the pier positions are set as solid regions and do not participate in the numerical calculation.

[0020] In step five of a specific embodiment, in the numerical simulation, the initial terrain before and after bridge construction remains the same, h2 = h1.

[0021] In step six of a specific embodiment, the pulsating velocity V′2 is calculated by formula (1)

[0022]

[0023] In step seven of a specific embodiment, the sediment settling velocity ω in still water at each grid node before bridge construction is calculated by the Zhang Ruijin settling velocity formula shown in formula (2):

[0024]

[0025] where υ is the dynamic viscosity coefficient; d is the sediment particle size; γ s is the sediment specific weight; γ is the water specific weight; g is the gravitational constant.

[0026] In step seven of a specific embodiment, the settling velocity ω affected by the turbulent kinetic energy at each grid node after bridge construction t is calculated by formula (3):

[0027]

[0028] In step eight of a specific embodiment, the sediment carrying capacity S* is calculated by formula (4):

[0029]

[0030] where u is the flow velocity; k is a coefficient; g is the gravitational acceleration; h is the water depth.

[0031] In step eight of a specific embodiment, the flow velocity and water depth outside the general scour range after bridge construction are basically the same as those before the project. Therefore, according to the sediment carrying capacity S* formula, the sediment carrying capacity intensity outside the general scour range before and after bridge construction is also the same; while within the general scour range, although the flow velocity and water depth have changed, when the general scour reaches the dynamic equilibrium state, the sediment carrying capacity inside and outside the general scour range should also be equal.

[0032] In step nine of a specific embodiment, the general scour amplitude is as shown in formula (10):

[0033] Δh = h1[(u2 / u1) 2 / 3 (ω / ω t ) 1 / 3 -1] (10)

[0034] The general scour depth Δh at each grid node position is calculated using Equation (10), and thus the characteristics of the general scour depth in the upstream and downstream areas of the bridge are obtained.

[0035] In Step 9 of a specific embodiment, it specifically includes: Considering that the flow velocity and water depth at each cross-section position are the same before bridge construction, the following Equation (5) can be obtained:

[0036]

[0037] where u 2s is the flow velocity in the state of balanced general scour; h 2s is the water depth in the state of balanced general scour, and ω ts is the settlement velocity in the state of balanced general scour;

[0038] Assuming that the discharge per unit width remains unchanged at each position during the scour process after bridge construction, then

[0039] u 2s h 2s = u2h1 (6)

[0040] Substituting Equation (6) into Equation (5) gives

[0041]

[0042] Finally, it can be obtained that

[0043] h 2s = h1[(u2 / u1) 2 / 3 (ω / ω ts ) 1 / 3 (8)

[0044] The general scour depth is defined as

[0045] Δh = h 2s - h1 (9)

[0046] Substituting Equation 9 into Equation 8, and assuming that the settlement velocities are basically the same ω ts = ω t under the balanced general scour, that is, when the scour after bridge construction has not developed, the following general scour depth formula can be obtained:

[0047] Δh = h1[(u2 / u1) 2 / 3 (ω / ω t ) 1 / 3 -1] (10)

[0048] The general scour amplitude Δh of each grid node position is calculated using formula (10), thereby obtaining the characteristics of the general scour amplitude in the upstream and downstream regions of the bridge.

[0049] The present invention improves the calculation method of the general scour pattern of a sea-crossing bridge. This method combines a planar three-dimensional numerical model and considers the influence of the turbulent flow effect of the sea-crossing bridge on sediment erosion and deposition, updates the calculation method of sediment-carrying capacity, and realizes the accurate prediction of the general scour pattern of the sea-crossing bridge, including depth and range, through the dynamic equilibrium theory, improving the calculation accuracy of the general scour pattern of the sea-crossing bridge. The method of the present invention overcomes the deficiency of only calculating the seabed erosion and deposition through the change of flow velocity in the past. It can not only obtain the maximum general scour depth of the bridge axis section, but also obtain the morphological characteristics of the general scour amplitude within the plane range, and the calculated general scour pattern is relatively consistent with the actual result.

[0050] In another aspect, the present invention aims at a measurement and control method for the general scour pattern of a sea-crossing bridge considering the turbulent effect, and the method includes at least one step in the aforementioned method.

[0051] In another aspect, the present invention aims at a measurement and control device, including a processor, a memory, and a program stored in the memory and executable on the processor. When the program runs, it executes at least one step in the aforementioned calculation method of the general scour pattern of the sea-crossing bridge considering the turbulent effect.

[0052] On the basis of conforming to the common knowledge in the field, the above preferred conditions can be combined with each other to obtain specific implementation manners.

[0053] The beneficial effects of the present invention are as follows:

[0054] 1) By combining a planar three-dimensional numerical model and considering the influence of the turbulent flow effect of the sea-crossing bridge on sediment erosion and deposition, the calculation method of sediment-carrying capacity is updated, and through the dynamic equilibrium theory, the accurate prediction of the general scour pattern of the sea-crossing bridge, including depth and range, is realized, improving the calculation accuracy of the general scour pattern of the sea-crossing bridge.

[0055] 2) The general scour calculation method is improved, and the influence of the turbulent flow effect of the sea-crossing bridge on sediment erosion and deposition is considered, overcoming the deficiency of only calculating the seabed erosion and deposition through the change of flow velocity in the past.

[0056] 3) It can not only obtain the maximum general scour depth of the bridge axis section, but also obtain the morphological characteristics of the general scour amplitude within the plane range, and the calculated general scour pattern is relatively consistent with the actual result.

[0057] The present invention adopts the above technical solutions to achieve the above purposes, making up for the deficiencies of the prior art, with reasonable design and convenient operation. Description of the Drawings

[0058] To enable those skilled in the art to more quickly and clearly understand the above and / or other purposes, features, advantages and examples of the present application, some attached drawings are provided. It should be noted that the attached drawings of the specification, schematic embodiments and their descriptions constituting the present application are used to provide a further understanding of the present application and do not constitute an improper limitation of the present application.

[0059] Figure 1 is the calculation flow chart of the present invention;

[0060] Figure 2 is the calculation area grid diagram in Embodiment 2 of the present invention;

[0061] Figure 3 is the local calculation grid diagram of each pier of the cross-sea bridge in Embodiment 2 of the present invention;

[0062] Figure 4 is the verification diagram of the tide level process line in Embodiment 2 of the present invention;

[0063] Figure 5 is the verification diagram of the flow velocity process line in Embodiment 2 of the present invention;

[0064] Figure 6 is the flood tide vector diagram before bridge construction in Embodiment 2 of the present invention;

[0065] Figure 7 is the flood tide vector diagram after bridge construction in Embodiment 2 of the present invention;

[0066] Figure 8 is the general scour amplitude distribution diagram in Embodiment 2 of the present invention;

[0067] Figure 9 is the variation of the general scour depth along the cross-section in the downstream direction in Embodiment 2 of the present invention. Detailed implementation manners

[0068] Those skilled in the art can draw on the content of this article and implement it by appropriately replacing and / or modifying process parameters. However, it should be particularly noted that all such similar replacements and / or modifications are obvious to those skilled in the art and are all considered to be included in the present invention. The content of the present invention has been described through preferred examples, and those skilled in the art can obviously make changes or appropriate alterations and combinations to the content described herein without departing from the content, spirit and scope of the present invention to implement and apply the technology of the present invention.

[0069] It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present application belongs.

[0070] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the technical solutions of the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should also be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0071] The present invention will be described in detail below.

[0072] Embodiment 1:

[0073] A calculation method for the general scour pattern of a cross-sea bridge considering the turbulence effect is provided. As Figure 1 shown, it specifically includes the following steps.

[0074] Step 1: Determine the research area including the cross-sea bridge project according to the water and sediment characteristics of the sea area where the cross-sea bridge is located, and perform three-dimensional grid division on the research area, where the piers of the cross-sea bridge are encrypted and divided according to the actual shape.

[0075] Step 2: Use the measured terrain data for terrain interpolation of each grid node to obtain the elevation of each grid node. For the hydrodynamic calculation before bridge construction, the elevation of the grid nodes at the pier positions is adopted from the actual terrain data. When calculating the hydrodynamic force after bridge construction, the grid at the pier positions is set as a solid area and does not participate in the numerical calculation.

[0076] Step 3: List all the boundary conditions within the calculation area, and select typical calculated hydrological boundary conditions according to the measured data.

[0077] Step 4: Establish a non-hydrostatic three-dimensional mathematical model including the entire cross-sea bridge project, and use the measured data to verify the tidal level and flow velocity to obtain an appropriate roughness value within the research area.

[0078] Step 5: Use the non-hydrostatic three-dimensional mathematical model to calculate the hydrodynamic fields before and after the completion of the cross-sea bridge. In the numerical simulation, the initial terrain before and after bridge construction remains the same. Obtain the pre-construction planar flow velocity u1, water depth h1, post-construction planar flow velocity u2, vertical flow velocity V2, water depth h2, and turbulent kinetic energy k2 at each grid node. Among them, since the terrain remains unchanged, h2 = h1.

[0079] Step 6: Calculate the pulsating velocity at each grid node using the relationship between turbulent kinetic energy and pulsating velocity

[0080]

[0081] Step 7: Calculate the sediment settlement velocity at each grid node before bridge construction using the Zhang Ruijin settlement velocity formula

[0082]

[0083] Where ω is the sediment settlement velocity in still water, υ is the dynamic viscosity coefficient, d is the sediment particle size, r s is the sediment specific gravity, and r is the water specific gravity.

[0084] Then, use the following formula to calculate the settlement velocity ω affected by the turbulent kinetic energy at each grid node after the bridge is built t :

[0085]

[0086] Step 8: According to the sediment-carrying capacity calculation formula of the fine-grained sediment model in the Hangzhou Bay estuary

[0087]

[0088] Where S* is the sediment-carrying capacity, u is the flow velocity, k is the coefficient, g is the acceleration due to gravity, and h is the water depth.

[0089] The flow velocity and water depth outside the general scour range after the bridge is built are basically the same as those before the project. Therefore, according to formula (4), the sediment-carrying capacity intensity outside the general scour range before and after the bridge is built is also the same. In the general scour range, although the flow velocity and water depth have changed, when the general scour reaches the dynamic equilibrium state, the sediment-carrying capacity inside and outside the general scour pit should also be equal.

[0090] Step 9: Considering that the flow velocity and water depth at each cross-section position are the same before the bridge is built, the following formula can be obtained:

[0091]

[0092] Where u 2s is the flow velocity in the state of balanced general scour, h 2s is the water depth in the state of balanced general scour, and ω ts is the settlement velocity in the state of balanced general scour.

[0093] Assume that the discharge per unit width at each position remains unchanged during the scour process after the bridge is built, then

[0094] u 2s h 2s = u2h1 (6)

[0095] Substitute formula (6) into formula (5) to obtain

[0096]

[0097] Finally, it can be obtained

[0098] h 2s = h1[(u2 / u1) 2 / 3 (ω / ω ts )1 / 3 (8)

[0099] The general scouring amplitude is defined as

[0100] Δh = h 2s - h1 (9)

[0101] Substitute Equation (9) into Equation (8), and assuming that the settlement velocities are basically the same ω under the condition of general scouring equilibrium, that is, when the scouring after bridge construction has not developed ts = ω t , the general scouring amplitude formula can be obtained as follows:

[0102] Δh = h1[(u2 / u1) 2 / 3 (ω / ω t ) 1 / 3 - 1] (10)

[0103] Calculate the general scouring amplitude Δh of the seabed at each grid node position using Equation (10), thereby obtaining the general scouring amplitude characteristics in the areas upstream and downstream of the bridge.

[0104] Example 2:

[0105] Based on the foregoing example, select the Zhoushan Link Island Project in the southern part of Hangzhou Bay, and the Jintang Bridge erected between Jintang Island and Ningbo as the research area to calculate the general scouring pattern, including the following steps.

[0106] The first part, determination of the research area

[0107] The southwestern part of the bridge sea area relies on the coasts of Zhenhai District and Beilun District on both sides of the Yongjiang Estuary, receiving the water from the Yongjiang River. The eastern part is blocked by islands such as Jintang Island, and is connected to the outer sea through the Jintang Waterway, forming a tidal channel from the Jintang Waterway to the inner Hangzhou Bay. The hydrodynamic conditions in the project sea area show typical characteristics of strong reciprocating tidal currents.

[0108] The second part, establishment and verification of the mathematical model

[0109] According to the main tasks of the large-scale numerical simulation and the requirements of the water boundary conditions, select the numerical simulation calculation domain as Figure 2 shown, with its boundaries: the northwest is the line from Haiwang Mountain to Dayu Mountain, the north is the line from Dayu Mountain to Zhoushan Mamu, and the east is the line from Shitou at Chuanshan Peninsula to Dinghai. The area of the calculation domain is 1215.58 km 2 . During the verification stage, a total of 7271 triangular elements and 3905 effective calculation nodes are arranged in the plane within the calculation domain, and it is divided into 15 layers vertically. As Figure 3As shown in the figure, the grid of each pier is encrypted according to its actual shape. Underwater topography: The underwater topographic map at a scale of 1:50,000 surveyed in November 2002 is used from Zhenlongpu Sluice to Tuni Mountain on Daxie Island, and the recent nautical charts are used for the rest. The maximum water depth in the area reaches more than 100 m, the minimum spatial step is 15 m, and the computational time step is 3 s.

[0110] The flow verification was carried out using the hydrological survey data in December 2002. In terms of accuracy, the average error of the tide level verification is 0.07 m (the maximum error of the high tide level is 0.17 m, and the maximum error of the low tide level is 0.17 m), and 88.3% of the errors are within 0.10 m. For the ebb and flood currents and the mean velocity at half tide, about 80% of the relative errors are less than 10%. Figure 4 and Figure 5 The verification of the tide level process line and the velocity process line are respectively given.

[0111] Part Three, hydrodynamic calculation before and after bridge construction

[0112] The verified non-hydrostatic plane three-dimensional mathematical model is used to calculate the hydrodynamic fields before and after the completion of Jintang Bridge. Figure 6 The figure shows the ebb and flood current loss map before bridge construction. It can be seen that the waters north of the west exit of Jintang Waterway are restricted by the Jintang Waterway and its trumpet-shaped boundary. The flood current directions are radial, and the ebb current directions are convergent. The tidal current paths are closely related to the morphology of the underwater topography in this sea area. The flood and ebb tides in the bridge area are basically in a reciprocating flow state, and generally flow along the isobath.

[0113] The flow field distribution at the flood peak near the piers after bridge construction is shown in Figure 7 , according to statistics, the changes in the flood and ebb peak velocities at the main navigation holes are relatively large, with the maximum changes in the flood and ebb tides being 19.8% and 18.7% respectively, and the velocity changes in other bridge sections are basically within 4%.

[0114] Part Four, calculation method for the general scour pattern of Jintang Bridge considering the turbulence effect

[0115] According to the calculated distribution of turbulent kinetic energy at each node, the pulsating velocity at each grid node is calculated using formula (1), the sediment settlement velocity at each grid node before bridge construction is calculated using formula (2), and the sediment settlement velocity under the influence of turbulence in the near area of the bridge after bridge construction is calculated using formula (3). On this basis, the general scour depth at each position in the bridge area is calculated using the seabed erosion and deposition equilibrium calculation formulas (4)-(10). The final calculated distribution of the general scour amplitude in the bridge area is shown in Figure 8 . Figure 9 For the Figure 8 along the flow direction, the figure shows the variation of the general scour along the A-A section in gm= 3.4 m. The further away from the bridge axis, the smaller the general scour amplitude generally is. The general scour range is roughly within 3.6 km upstream and downstream of the bridge site. The general scour depth and morphological characteristics obtained by this method are in good agreement with the actual results.

[0116] The method of the present invention combines a plane three-dimensional numerical model and takes into account the influence of the turbulent flow effect of the sea-crossing bridge on sediment erosion and deposition, updates the sediment-carrying capacity calculation method, and realizes the accurate prediction of the general scour morphology of the sea-crossing bridge, including depth and range, through the dynamic equilibrium theory. Taking the Jintang Bridge as an example, it is verified that the method of the present invention can improve the calculation accuracy of the general scour morphology of the sea-crossing bridge, overcomes the deficiency of only calculating the seabed erosion and deposition through the change of flow velocity in the past, can not only obtain the maximum general scour depth of the bridge axis section, but also obtain the morphological characteristics of the general scour amplitude within the plane range. The verification shows that the calculated general scour morphology is in good agreement with the actual results. Therefore, the method of the present invention can be used for the accurate prediction of the general scour morphology of the sea-crossing bridge, including depth and range.

[0117] The conventional technologies in the above embodiments are the existing technologies known to those skilled in the art, so they will not be described in detail here.

[0118] The specific embodiments described herein are merely illustrative of the spirit of the present invention. Those skilled in the art of the present invention can make various modifications or supplements to the described specific embodiments or use similar methods to replace them, but will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

[0119] Although a detailed description of the present invention has been made and some specific embodiments have been cited, it is obvious that various changes or modifications can be made by those skilled in the art without departing from the spirit and scope of the present invention.

[0120] The above are only the preferred embodiments of the present application and are not used to limit the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included within the protection scope of the present application.

[0121] Matters not covered by the present invention are all well-known technologies.

Claims

1. A calculation method for the general scour pattern of cross-sea bridges considering the turbulence effect, characterized in that It includes the following steps: Step 1: Determine the research area including the cross-sea bridge project, conduct three-dimensional grid division on the research area, and perform grid encryption division on each pier of the cross-sea bridge according to the actual shape; Step 2: Interpolate the terrain of each node of the three-dimensional grid using the measured terrain data to obtain the elevation of each grid node; Step 3: List all boundary conditions within the calculation area, and select typical calculated hydrological boundary conditions according to the measured data; Step 4: Establish a non-hydrostatic three-dimensional mathematical model including the entire cross-sea bridge project, verify the tidal level and flow velocity using the measured data, and obtain the appropriate roughness value within the research area; Step 5: Use a non-hydrostatic three-dimensional mathematical model to calculate the hydrodynamic fields before and after the completion of the cross-sea bridge; obtain the pre-project planar flow velocity at each grid node , water depth , the post-project planar flow velocity , vertical flow velocity , water depth and turbulent kinetic energy ; Step 6: Calculate the pulsating velocity at each grid node by using the relationship between the turbulent kinetic energy and the pulsating velocity ; Step 7: Calculate the sediment settlement velocity in still water at each grid node before bridge construction using the Zhang Ruijin sedimentation velocity formula ; Then calculate the settlement velocity affected by turbulent kinetic energy at each grid node after bridge construction ; Step 8: Calculate the sediment carrying capacity according to the estuarine fine sediment model ; Considering that the flow velocity and water depth at each cross-section position are the same before bridge construction, the sediment carrying capacity inside and outside the general scouring range should also be equal; Step 9: Assume that the discharge per unit width at each position remains unchanged during the scour process after bridge construction. At the same time, assume that the settlement velocities are basically the same under the general scour equilibrium, that is, when the scour after bridge construction has not developed. , and then the general scour amplitude formula can be obtained. Then, calculate the general scour amplitude of the seabed at each grid node position, so as to obtain the characteristics of the general scour amplitude in the upstream and downstream areas of the bridge.

2. The method according to claim 1, characterized in that: In Step 5, the initial terrain before and after bridge construction in the numerical simulation remains the same. .

3. The method according to claim 2, characterized in that: In Step 6, the pulsation velocity is calculated by Equation (1) (1)。 4. The method according to claim 3, characterized in that: In Step 7, the sediment settling velocity in still water at each grid node before bridge construction is calculated by the Zhang Ruijin settling velocity formula shown in Equation (2): (2) Among them, is the dynamic viscosity coefficient; is the sediment particle size; is the sediment unit weight; is the water unit weight; is the gravitational constant.

5. The method according to claim 4, characterized in that: In Step 7, the settlement velocity under the influence of turbulent kinetic energy at each grid node after bridge construction Calculated by formula (3): (3)。 6. The method according to claim 5, characterized in that: In Step 8, the sediment-carrying capacity is calculated by Equation (4): (4) Among them, is the flow velocity; is the coefficient; is the acceleration due to gravity; is the water depth; The flow velocity and water depth outside the general scouring range after bridge construction are basically the same as those before the project. Therefore, according to the sediment-carrying capacity formula, the sediment-carrying capacity intensity outside the general scouring range before and after bridge construction is also the same. In the general scouring range, although the flow velocity and water depth have changed, when the general scouring reaches the dynamic equilibrium state, the sediment-carrying capacity inside and outside the general scouring range should also be equal.

7. The method according to claim 1 or 6, characterized in that: In Step 9, the general scouring amplitude is shown in formula (10): (10) Calculate the general scouring amplitude of the seabed at the positions of each grid node using formula (10). Thus, the characteristics of the general scouring amplitude in the upstream and downstream areas of the bridge are obtained.

8. The method according to claim 6, wherein: Step 9 includes: Considering that the flow velocity and water depth at each cross-section position are the same before bridge construction, formula (5) can be obtained: (5) Among them, is for balancing the flow velocity under the general scouring state; is the water depth for balancing the general scouring state, is the settlement velocity for balancing the general scouring state; Assume that the discharge per unit width at each position remains unchanged during the scouring process after bridge construction, then (6) After substituting formula (6) into formula (5), it can be obtained that (7) Finally, it can be obtained that (8) The general scouring amplitude is defined as (9) Substitute Equation (9) into Equation (8), and assume that the settlement rates are basically the same under general scour equilibrium, i.e., when the scour has not developed after bridge construction. The general scour amplitude formula can be obtained as follows: (10) Calculate the general scour amplitude of the seabed at each grid node position using formula (10). Thus, the characteristics of the general scour amplitude in the upstream and downstream areas of the bridge are obtained.

9. A measurement and control method for the general scouring pattern of a sea-crossing bridge considering the turbulence effect, characterized in that: The method includes the steps in the method described in any one of claims 1-8.

10. A measurement and control device, comprising a processor, a memory, and a program stored in the memory and executable on the processor, characterized in that: When the program runs, it executes the steps in the method for calculating the general scouring pattern of a cross-sea bridge considering the turbulent effect described in any one of claims 1-8.

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