A design method of slope normal grading artificial base structure

Abstract

The application provides a slope normal grading artificial subgrade structure design method, relates to the technical field of subgrade structure design, and performs fitting on the elevation point cloud in underwater bedrock terrain data, and outputs normal grading section data; determines the normal grading series according to the slope of the slope surface in the normal grading section data, so as to obtain normal grading geometric parameters; extracts the section front profile from the normal grading section data, divides the stake area and the front area according to the section front profile, and outputs the partitioned filler design parameters; calculates the sliding force step by step along the tangent of the slope surface, and outputs the grading stability determination result according to the sliding force statistics tangential anti-skid safety factor and the normal shear safety factor; performs geometric lofting and parameter association on the normal grading section data, the normal grading geometric parameters, the partitioned filler design parameters and the grading stability determination result, and outputs a three-dimensional parameterized subgrade graphic file, so that the normal grading design precision and stability are improved.

Description

Technical Field

[0001] This invention relates to the field of subgrade structure design technology, specifically a method for designing a sloping, normal-graded artificial subgrade structure. Background Technology

[0002] Sloping artificial foundations are the core load-bearing structures for deep-water wharves, gravity structures, and island / reef access projects. Their design rationality directly determines the long-term service stability and construction cost control level of hydraulic structures in complex wave and current environments, making them a core research object in the field of port geotechnical engineering. As deep-water shoreline development extends to steeply sloping bedrock areas, the traditional design mode relying on manual experience iteration is no longer suitable for the refined control requirements under complex slopes. The industry is gradually transforming towards a digital design paradigm characterized by topographic data-driven design, parametric grading, automatic verification, and three-dimensional collaborative delivery.

[0003] Conventional slope-type subgrade design methods generally use a global horizontal-vertical coordinate system as the design benchmark. By selecting several representative locations distributed longitudinally, the bedrock slope is vertically sectioned, and the resulting two-dimensional cross-section is used as the design carrier. Using the total vertical subgrade thickness of the cross-section as input, after matching the empirical grading number, the lateral indentation dimension of the steps and the slope ratio of the exposed slope of adjacent steps are determined in the horizontal direction. The coastal protection zone and the landside main zone are divided in the horizontal direction, and the specifications and paving width of the protection blocks are selected based on engineering experience. The horizontal downward sliding force generated by the overall self-weight of the subgrade is used as the verification load to check the overall anti-sliding stability of the cross-section, and finally, the two-dimensional cross-section design results are output.

[0004] However, the above scheme has technical limitations: the grading benchmark uses a global horizontal axis instead of the normal of the typical design section of bedrock, which leads to systematic misjudgments of the geometric deviation between the step tangential and the original slope surface, the stress concentration between stages, and the effective bearing thickness in the normal direction. In addition, the toe protection design does not couple the wave load along the normal erosion path of the slope surface, the gradation of the boulders is out of sync with the anchoring requirements of the last stage, and the scour resistance is not targeted. The stability verification uses an overall equivalent load, does not distinguish the difference in fill weight between the adjacent pile area and the front edge area, ignores the graded stress characteristics and the independent verification dimension of normal shear resistance, and the judgment accuracy is difficult to match the requirements of steep slope conditions.

[0005] The information disclosed in the background section is only intended to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0006] The purpose of this invention is to provide a design method for a sloping, normal-graded artificial foundation bed structure to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: A design method for a sloping, normal-graded artificial subgrade structure, comprising the following steps: S1. Acquire underwater bedrock topographic data and control boundary data, fit the elevation point cloud in the underwater bedrock topographic data to generate a continuous bedrock slope surface, extract typical design sections based on the control boundary data, establish a local coordinate system with the normal of the typical design section as the grading reference axis, and output normal graded section data. S2. Determine the normal grade level based on the slope gradient in the normal grade section data, and couple the solution of the normal filling thickness, step lateral indentation dimension and exposed slope ratio of adjacent steps of each grade subgrade to obtain the normal grade geometric parameters. S3. Extract the front profile of the cross section from the normal graded cross section data, divide the adjacent pile area and the front profile according to the front profile, map the filling type of the adjacent pile area and the front profile, combine the wave flow parameters and slope in the normal graded cross section data, back calculate the toe protection block gradation and toe protection width for the front profile, and output the partitioned filling design parameters including the filling parameters of the adjacent pile area and the filling parameters of the front profile. S4. Based on the normal graded geometric parameters and the zoned fill design parameters, calculate the sliding force step by step along the tangential direction of the slope, calculate the tangential anti-sliding safety factor and the normal shear safety factor based on the sliding force, and output the graded stability judgment result. S5. Using the local coordinate system as the kernel, geometric layout and parameter association are performed on the normal graded cross section data, normal graded geometric parameters, zoned filler design parameters and graded stability judgment results, and a three-dimensional parameterized subgrade primitive file is output.

[0008] Furthermore, the elevation point cloud in the underwater bedrock topographic data is fitted to generate a continuous bedrock slope surface. The specific steps are as follows: Read the elevation point cloud from the underwater bedrock topographic data, remove outlier points in the elevation point cloud, and output standard elevation point cloud data; The Kriging interpolation algorithm is used to perform grid fitting on standard elevation point cloud data, and the initial slope fitting surface is output. The tangent plane is calculated for each grid patch in the initial slope fitting surface to obtain the tangent plane of the grid patch, and the corresponding normal vector is determined according to the tangent plane. The normal vector is then bound to each grid patch to form a normal attribute fitting surface. The leading edge positioning information in the control boundary data is projected onto the normal attribute fitting surface to obtain the leading edge clipping line. The normal attribute fitting surface is clipped along the leading edge clipping line to form a continuous bedrock slope surface.

[0009] Furthermore, based on the control boundary data, typical design sections are extracted, and a local coordinate system is established using the normal of the typical design section as the grading reference axis. The normal grading section data is then output. The specific steps are as follows: Projection analysis is performed on the leading edge positioning information in the control boundary data to extract slope change feature points. The slope change feature points in the continuous bedrock slope surface are used as cutting positions, and supplementary cutting positions are set between adjacent cutting positions at a preset interval. The continuous bedrock slope surface is vertically cut according to the cutting position and the supplementary cutting position to obtain a set of candidate sections; Each cross section in the candidate cross section set is labeled with its corresponding longitudinal station number and defined as a typical design cross section; The normal vectors of each grid patch are extracted from the typical design section with station numbers. The normal vectors of each grid patch are averaged and fitted to determine the normal of the typical design section. A local coordinate system is established using the slope tangent in the typical design section as the auxiliary axis and the normal of the typical design section as the graded reference axis. The local coordinate system is then bound to the typical design section to form a coordinate typical design section. According to the local coordinate system, the corresponding slope gradient, bedrock elevation, section front profile, wave flow parameters and longitudinal station number are extracted from the typical design section of the coordinate system and integrated to form normal graded section data.

[0010] Furthermore, the normal grade level is determined based on the slope gradient in the normal grade section data, and the normal filling thickness, lateral indentation dimension of the step, and slope ratio of the exposed side slope of adjacent steps of each grade subgrade are coupled and solved to obtain the normal grade geometric parameters. The specific steps are as follows: Read the slope gradient from the normal graded cross section data, match the slope gradient according to the preset slope graded interval, and obtain the normal graded level. Extract the control elevation of the top surface of the subgrade from the control boundary data, and calculate the vertical elevation difference with the bedrock slope elevation in the normal graded section data. Determine the total normal thickness of the subgrade along the normal direction of the typical design section based on the vertical elevation difference and the slope gradient. The total normal thickness of the subgrade is discretized into normal filling thicknesses of each level according to the normal grade. Based on the normal filling thickness, the lateral recess dimension of the corresponding step and the slope ratio of the exposed side slope of the adjacent step are determined. The lateral inward dimensions of the steps, the slope ratio of the exposed side slope of adjacent steps, and the normal filling thickness at each level are summarized, and the normal graded geometric parameters are output.

[0011] Furthermore, the profile of the leading edge of the cross-section is extracted from the normal graded cross-section data, and the adjacent pile area and the leading edge area are divided according to the profile of the leading edge of the cross-section. The specific steps are as follows: Extract the local coordinates of the front profile of the cross section in the bound local coordinate system from the normal graded cross section data; The leading edge zone is delineated by extending a predetermined distance along the normal of the typical design section towards the sea using local coordinates, and the adjacent pile zone is delineated along the normal of the typical design section towards the land to the control elevation of the top surface of the foundation bed.

[0012] Furthermore, the filling type is mapped between the adjacent pile area and the leading edge area. Combining the wave flow parameters and slope gradient in the normal graded cross-sectional data, the toe protection riprap gradation and toe protection width are calculated in reverse for the leading edge area. The resulting zonal filling design parameters, including filling parameters for the adjacent pile area and the leading edge area, are output. The specific steps are as follows: Based on the preset filling type, the filling type matching was carried out for the adjacent pile area and the front edge area to determine the filling parameters of the adjacent pile area and the front edge area. Based on the wave flow parameters, slope gradient, and final normal boundary in the normal graded geometric parameters of the normal graded cross section data, the stable weight of the toe stone corresponding to the fill parameters in the front zone is calculated according to the erosion stability relationship of the boulders, and the gradation of the toe stone is determined based on the stable weight and the final normal boundary. The defined range along the normal direction of the typical design section of the leading edge area is read, and the defined range is corrected in combination with wave and current parameters to obtain the toe width; The parameters of the fill material in the adjacent pile area, the parameters of the fill material in the leading edge area, as well as the gradation of the toe protection boulders and the width of the toe protection, are associated and integrated with the corresponding normal grading levels to output the design parameters of the zonal fill material.

[0013] Furthermore, based on the normal graded geometric parameters and the zoned filler design parameters, the sliding force is calculated step by step along the tangential direction of the slope. The specific steps are as follows: Extract the normal filling thickness, step lateral indentation dimension and corresponding zone of each level from the normal graded geometric parameters, and match the fill stone unit weight of the corresponding zone in the zone fill design parameters to obtain graded unit weight data. Calculate the volume of filler per unit width for each level of the subgrade under a typical design section, and multiply the volume of filler per unit width by the corresponding specific weight to obtain the self-weight of each level of the subgrade. Multiply the self-weight of each level of subgrade by the sine value of the slope gradient in the normal graded cross-sectional data to obtain the sliding force of each level of subgrade along the tangential direction of the slope.

[0014] Furthermore, based on the sliding force statistics of the tangential anti-slip safety factor and the normal shear safety factor, the graded stability judgment result is output. The specific steps are as follows: Obtain the internal friction angle and cohesion of each packing in the design parameters of the partitioned packing. Combine the sliding force and the slope ratio of the exposed side slope of the adjacent steps of the corresponding grade to calculate the anti-sliding force along the tangential direction of the slope for each grade. The tangential anti-slip safety factor is obtained by dividing the anti-slip force along the tangential direction of the slope at each level by the corresponding sliding force. The self-weight of each level of subgrade bed is decomposed into normal components according to the slope. The normal component, the corresponding normal filling thickness, the internal friction angle of the filling material, and the cohesion are combined to calculate the normal shear force per unit width. The ratio of the normal shear force per unit width to the normal component is used as the normal shear safety factor. Preset tangential anti-slip threshold and preset normal shear threshold; The tangential anti-slip safety factor and normal shear safety factor for each normal grade are compared with the corresponding preset tangential anti-slip threshold and preset normal shear threshold. If the tangential anti-slip safety factor of any first-level normal grade is greater than or equal to the preset tangential anti-slip threshold, and the normal shear safety factor is greater than or equal to the preset normal shear threshold, the current-level subgrade is determined to be stable. If the tangential anti-slip safety factor of any first-level normal grade is less than the preset tangential anti-slip threshold, or the normal shear safety factor is less than the preset normal shear threshold, the current-level subgrade is determined to be unstable. By summarizing the determination information of each level of normal direction classification, the classification stability determination result is obtained.

[0015] Furthermore, using a local coordinate system as the core, the normal graded cross-sectional data, normal graded geometric parameters, zoned filler design parameters, and graded stability judgment results are geometrically laid out and parameterized, outputting a three-dimensional parametric subgrade primitive file. The specific steps are as follows: Using the local coordinate system as a reference, the typical design sections with longitudinal station numbers in the normal graded section data are arranged as control lines along the local coordinate system to obtain the section control line set. Based on the local coordinate system, starting from the front profile of the cross section, along the normal direction of the typical design cross section, the normal filling thickness of each level is superimposed in sequence. Combined with the lateral indentation of the step, the horizontal offset is calculated, and the inner and outer boundary coordinates of each step are obtained, which are the level boundary positions. According to the normal filling thickness of each level, the lateral indentation size of the steps, and the position of the grade boundary, the cross-section control line set is continuously laid out and surface fitted along the longitudinal direction of the subgrade, and the graded structure of each level of normal is constructed layer by layer to obtain the complete three-dimensional geometric structure of the subgrade. The normal graded cross-sectional data, normal graded geometric parameters, zoned filler design parameters, and graded stability determination results are correlated and mapped to the three-dimensional geometry of the subgrade, and a three-dimensional parametric subgrade primitive file is output.

[0016] Compared with the prior art, the beneficial effects of the present invention are: This invention obtains underwater bedrock topographic data and control boundary data to fit a continuous bedrock slope surface. It establishes a local coordinate system with the normal of a typical design section as the grading reference axis and outputs normal grading section data. This realizes the essential transformation of the design reference from the global horizontal and vertical axis to the slope normal. This ensures that all subsequent grading and verification are carried out along the actual stress direction of the slope, effectively avoiding the systematic misjudgment of normal filling thickness and stress concentration between levels caused by traditional horizontal grading. Based on the normal grading section data, the normal filling thickness of each level, the lateral indentation of the step, and the slope ratio of the exposed slope of adjacent steps are coupled and solved. Combined with wave and current parameters, the gradation of the riprap in the leading edge area and the width of the toe are deduced. This achieves normal coupling matching between the geometry of the subgrade and the erosion resistance requirements of the toe. This allows the toe to form an effective anchorage to the final step along the slope erosion path, significantly improving the targeting of the toe's erosion resistance and the overall structural stability. By calculating the sliding force along the tangential direction of the slope and separately calculating the tangential anti-sliding safety factor and the normal shear safety factor, the precise quantitative determination of the graded stress characteristics is achieved, so that the stability state of each step can be independently verified. The difference in the density of the fill material between the adjacent pile area and the front edge area is fully considered, and the independent verification dimension of the normal shear is added. This effectively avoids the accuracy deviation caused by the overall equivalent verification and significantly improves the accuracy of stability determination and engineering safety under steep slope conditions. Attached Figure Description

[0017] Figure 1 This is a flowchart illustrating a method for designing a sloping, normal-graded artificial subgrade structure according to this embodiment. Figure 2 This is a graph showing the relationship between the stable weight of the foot protection stones and the matching particle size as a function of wave height in this embodiment. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments.

[0019] It should be noted that, unless otherwise defined, the technical or scientific terms used in this invention should have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0020] Example: Please see Figure 1 , Figure 1 This is a flowchart illustrating a method for designing a sloping, normal-graded artificial subgrade structure according to this embodiment. Specifically: A design method for a sloping, normal-graded artificial subgrade structure, comprising the following steps: S1. Acquire underwater bedrock topographic data and control boundary data, fit the elevation point cloud in the underwater bedrock topographic data to generate a continuous bedrock slope surface, extract typical design sections based on the control boundary data, establish a local coordinate system with the normal of the typical design section as the grading reference axis, and output normal graded section data.

[0021] The underwater bedrock topographic data was collected using a multibeam echo sounder. The multibeam echo sounder emits acoustic pulses and receives reflected signals from the seabed. Based on the round-trip time and sound velocity profile of the sound waves, the three-dimensional coordinates of each point on the seabed are statistically analyzed to obtain the underwater bedrock topographic data. The control boundary data was obtained through engineering surveys and data processing. The engineering surveys included land control surveys and water positioning surveys. The data processing summarized the subgrade construction area, the elevation of the top surface of the subgrade, and the water environment parameters. The control boundary data included the frontal positioning information, the control elevation of the top surface of the subgrade, and wave and current parameters. The frontal positioning information was a spatial curve of the frontal position of the subgrade, which was composed of a series of ordered coordinate points.

[0022] The system reads elevation point clouds from underwater bedrock topographic data, removes outliers from the elevation point clouds, and outputs standard elevation point cloud data. The elevation point cloud consists of several spatial points, each carrying three-dimensional coordinate information. The removal of outliers is based on the statistical characteristics of the neighborhood elevation. For each spatial point in the elevation point cloud, all spatial points in its neighborhood are searched, and the average elevation and standard deviation of the neighborhood spatial points are calculated. When the elevation difference between a spatial point and its neighbors exceeds three times the standard deviation, the spatial point is identified as an outlier and removed from the elevation point cloud. After all outliers are removed, the remaining set of spatial points constitutes the standard elevation point cloud data. The three-times-standard-deviation rule is based on the statistical 3σ criterion. Elevation data obtained through normal measurement follows an approximately normal distribution, with the mean ± three times the standard deviation covering the vast majority of valid observations. Elevation differences outside this range are caused by measurement equipment errors or environmental interference.

[0023] The Kriging interpolation algorithm is used to perform gridding fitting on standard elevation point cloud data, and the initial slope fitting surface is output.

[0024] Specifically, the Kriging interpolation algorithm uses all spatial points in the standard elevation point cloud data as known sampling points to construct a regular grid within the fitting region. The elevation of each grid node is estimated by weighted summation of the standard elevation point cloud data of the surrounding known sampling points and weight coefficients. The weight coefficients are calculated to satisfy the unbiased estimation condition and the condition of minimizing the estimation variance. The weight coefficients are determined by the variogram between the sampling points; that is, the distance between the sampling points is substituted into the variogram to obtain the spatial relationship values. The spatial relationship values ​​are then substituted into the Kriging equations, and under the conditions of unbiased estimation and minimizing the estimation variance, the equations are solved to obtain the weight coefficients of each sampling point. The variogram describes the variation of the spatial point elevation value with distance and is obtained by fitting the experimental variogram of the standard elevation point cloud data. The formula for estimating the grid node elevation is: In the formula, Indicates the estimated elevation of the grid nodes. Indicates the index of the known sampling point. ; This indicates the number of known sampling points involved in the estimation; Indicates the first Weighting coefficients for each known sampling point; Indicates the first The measured elevation of a known sampling point is obtained by transmitting acoustic pulses from a multibeam echo sounder and receiving underwater reflection signals. The three-dimensional coordinates of each point on the seabed are statistically analyzed based on the round-trip time and sound velocity profile of the sound waves, and the elevation value is extracted from the three-dimensional coordinates.

[0025] The process involves calculating the tangent plane for each mesh patch in the initial slope fitting surface, obtaining the tangent plane of the mesh patch, and determining the corresponding normal vector based on the tangent plane. The normal vector is then bound to each mesh patch to form a normal attribute fitting surface. Specifically, the initial slope fitting surface is composed of several mesh patches, each carrying the three-dimensional coordinates of its mesh nodes. For a single mesh patch, the coordinates of three non-collinear mesh nodes are extracted, and the two edge vectors connecting the mesh nodes are solved. These two edge vectors are then multiplied to obtain a normal vector perpendicular to the plane containing the mesh patch, with the normal vector pointing outwards from the initial slope fitting surface. The plane containing the mesh patch is defined by the mesh node coordinates and the normal vector, and this plane is the tangent plane. The normal vector is associated with the mesh patch and stored, allowing each mesh patch to carry the corresponding normal vector information. After all mesh patches have completed the tangent plane calculation and normal vector binding, a normal attribute fitting surface is formed.

[0026] In this embodiment, the leading edge positioning information in the control boundary data is projected onto the normal attribute fitting surface to obtain the leading edge clipping line. The normal attribute fitting surface is clipped along the leading edge clipping line to form a continuous bedrock slope surface. The leading edge positioning information is a spatial curve in the control boundary data that defines the position of the bedrock leading edge. The projection operation is performed along the normal vector direction of each grid patch of the normal attribute fitting surface, and the feature points on the leading edge positioning information are vertically projected onto the grid patches of the normal attribute fitting surface. The projection intersections are connected in sequence to form a spatial intersection line, which is the leading edge clipping line. The normal attribute fitting surface is clipped along the leading edge clipping line, and the curved surface part on one side of the leading edge clipping line is retained, which is the continuous bedrock slope surface.

[0027] Projection analysis is performed on the leading edge positioning information in the control boundary data to extract slope change feature points. The slope change feature points in the continuous bedrock slope surface are used as cutting positions, and supplementary cutting positions are set between adjacent cutting positions at preset intervals.

[0028] Specifically, the leading edge positioning information is vertically projected onto the continuous bedrock slope surface, and the local slope value of the continuous bedrock slope surface is calculated along the projection line. The slope change feature point is the location where the local slope value changes abruptly on the continuous bedrock slope surface. The criterion for judging the abrupt change of the local slope value is that the slope difference between two adjacent points exceeds the preset slope threshold. Points in the continuous bedrock slope surface that meet the abrupt change judgment criteria are extracted and recorded as slope change feature points. The position of the slope change feature point on the continuous bedrock slope surface is determined as the cutting position. Between two adjacent cutting positions, additional position points are evenly inserted along the continuous bedrock slope surface at a preset interval. The additional position points are recorded as supplementary cutting positions.

[0029] It should be noted that the preset slope threshold is set according to the construction grading specifications of the sloping normal graded artificial subgrade, and the specific value is determined by the technicians based on the maximum allowable single-level slope change value in the experience of subgrade grading in port engineering; the preset spacing is set according to the underwater subgrade cross-section measurement specifications and construction layout accuracy requirements, and the specific value is determined by the technicians based on the conventional point spacing standards collected from the underwater topographic cross-section.

[0030] The continuous bedrock slope surface is vertically cut according to the cutting position and the supplementary cutting position. Each vertical cut produces a cross-sectional outline, and the candidates are collected to obtain a set of candidate cross-sections. Each cross-section in the set of candidate cross-sections is labeled with a corresponding longitudinal station and defined as a typical design cross-section. The longitudinal station is a linear coordinate identifier arranged along the longitudinal direction of the subgrade, and the longitudinal station value corresponds one-to-one with the position of the cross-sectional outline on the continuous bedrock slope surface.

[0031] The normal vectors of each grid patch are extracted from the typical design section with stationing. The normal vectors of each grid patch are then averaged and fitted to determine the normal of the typical design section. Specifically, the typical design section with stationing is obtained by cutting a continuous bedrock slope surface. The surface of the typical design section with stationing retains grid patches and the normal vectors bound to the grid patches. All grid patches on the typical design section with stationing are traversed, and the normal vector corresponding to each grid patch is read one by one. After all normal vectors are collected, an average fitting operation is performed. The average fitting adopts the vector addition method to calculate the average. The corresponding coordinate components of all normal vectors are summed and then divided by the total number of normal vectors to obtain the average vector. The average vector is then normalized, and the normalized average vector is the normal of the typical design section.

[0032] In this embodiment, a local coordinate system is established using the slope tangent in the typical design section as an auxiliary axis and the normal of the typical design section as a grading reference axis. The local coordinate system is then bound to the typical design section to form a coordinate typical design section. The slope tangent is the tangent direction at any point on the outline of the typical design section, and the tangent direction is arranged along the extension direction of the section. The grading reference axis direction is taken as the direction of the normal of the typical design section. The origin of the local coordinate system is selected at a designated reference point on the typical design section. The direction of the first coordinate axis of the local coordinate system is aligned with the slope tangent, the direction of the second coordinate axis of the local coordinate system is aligned with the grading reference axis, and the direction of the third coordinate axis of the local coordinate system is obtained by the cross product of the first and second coordinate axes. The parameters of the local coordinate system are associated and stored with the data records of the typical design section. The typical design section after association and storage is called the coordinate typical design section.

[0033] Based on the local coordinate system, the corresponding slope gradient, bedrock elevation, section front profile, wave flow parameters and longitudinal station number are extracted from the typical design section of the coordinate system and integrated to form normal graded section data; It should be noted that the local coordinate system provides a coordinate transformation benchmark, and the geometric information on the typical design section of the coordinate system is converted into local coordinate values ​​through the local coordinate system; the slope gradient is calculated by the difference in local coordinates between adjacent points on the typical design section of the coordinate system; the bedrock slope elevation is the elevation value of the bedrock surface on the typical design section of the coordinate system; the profile of the leading edge of the section is formed by connecting the local coordinate points at the leading edge position on the typical design section of the coordinate system in sequence; the wave and current parameters are read from the external working condition data file and matched with the longitudinal station number of the current typical design section of the coordinate system, and the wave and current parameters include wave height and velocity values; the longitudinal station number is the station number value already marked on the typical design section of the coordinate system; the slope gradient, bedrock slope elevation, profile of the leading edge of the section, wave and current parameters, and longitudinal station number are organized and arranged according to a unified data structure, and the data set after organization is the normal graded section data.

[0034] S2. Determine the normal grade level based on the slope gradient in the normal grade section data, and couple the solution of the normal filling thickness, step lateral indentation dimension and exposed slope ratio of adjacent steps for each grade of subgrade to obtain the normal grade geometric parameters.

[0035] In this embodiment, the slope gradient in the normal grading section data is read, and the slope gradient is matched according to the preset slope grading interval to obtain the normal grading level. The preset slope grading interval is set according to the engineering specifications for the construction grading of sloping normal grading artificial subgrade. The preset slope grading interval divides the slope range into several intervals, and each interval corresponds to a determined normal grading level. The slope gradient is compared with each interval one by one, and the normal grading level corresponding to the interval into which the slope gradient falls is the matching result.

[0036] The control elevation of the top surface of the subgrade is extracted from the control boundary data, and the vertical elevation difference is calculated by comparing it with the bedrock slope elevation in the normal graded cross-section data. Based on the vertical elevation difference and the slope gradient, the total normal thickness of the subgrade along the normal direction of the typical design cross-section is determined. The total normal thickness of the subgrade is obtained by dividing the vertical elevation difference by the cosine value of the slope gradient. The formula for calculating the total normal thickness of the subgrade is as follows: In the formula, Indicates the total thickness of the base bed in the normal direction. Indicates the vertical height difference. This indicates the slope of the slope, in degrees.

[0037] The total normal thickness of the subgrade bed is discretized into normal fill thicknesses for each level according to the normal grade. Using the normal fill thickness as a benchmark, the lateral recess dimension of the corresponding step and the slope ratio of the exposed slope of adjacent steps are determined. Specifically, the discretization operation divides the total normal thickness of the subgrade bed into several layers equal to the number of normal grade levels. The thickness value of each layer is the normal fill thickness for each level. The normal fill thickness values ​​for each level are recorded one by one, forming a graded thickness sequence. The slope ratio of the exposed slope of adjacent steps is the ratio of the normal fill thickness for each level to the lateral recess dimension of the step. The lateral recess dimension of the step is obtained by multiplying the normal fill thickness for each level by the tangent of the slope gradient. The calculation formula is as follows: In the formula, This indicates the lateral indentation dimension of the step under a single-width condition. Indicates the thickness of the fill in the normal direction at each level; The lateral inward dimensions of the steps, the slope ratio of the exposed side slope of adjacent steps, and the normal filling thickness of each level are arranged and organized in order of grade level, and the normal grade geometric parameters are output.

[0038] S3. Extract the front profile of the cross section from the normal graded cross section data, divide the adjacent pile area and the front profile according to the front profile, map the filling type of the adjacent pile area and the front profile, combine the wave flow parameters and slope in the normal graded cross section data, back calculate the gradation of the toe stone and the width of the toe protection in the front profile, and output the partitioned filling design parameters including the filling parameters of the adjacent pile area and the filling parameters of the front profile.

[0039] In this embodiment, the local coordinates of the front profile of the cross section under the bound local coordinate system are extracted from the normal graded cross section data. The extraction process is as follows: traverse the front profile of the cross section stored in the normal graded cross section data, read the local coordinate system coordinate values ​​bound to each profile point on the front profile of the cross section in sequence, and arrange the read coordinate values ​​according to the arrangement order of the profile points to obtain the local coordinates of the front profile of the cross section under the bound local coordinate system.

[0040] The leading edge zone is delineated by extending a predetermined distance along the normal of the typical design section towards the sea using local coordinates, and the adjacent pile zone is delineated along the normal of the typical design section towards the land to the control elevation of the top surface of the foundation bed.

[0041] It should be noted that the preset distance is a pre-set length value, which is determined according to the relevant engineering specifications for the protection range of the underwater foundation. The seaward extension operation starts from the local coordinate point of the front profile of the cross section and moves the preset distance along the positive direction of the normal of the typical design cross section. The endpoint of the translation constitutes the outer boundary of the front area. The area between the front profile of the cross section and the outer boundary is called the front area. The landward delineation operation starts from the local coordinate point of the front profile of the cross section and extends along the opposite direction of the normal of the typical design cross section to the horizontal plane where the control elevation of the top surface of the foundation is located. The area covered by the extension is called the adjacent pile area.

[0042] Based on the preset filler type, filler type matching is carried out for the adjacent pile area and the front edge area to determine the filler parameters for the adjacent pile area and the front edge area.

[0043] Specifically, the data for the preset filler types comes from the geological survey and laboratory geotechnical tests conducted in the early stages of the project. During the survey phase, soil and rock samples were taken from the subgrade construction area and surrounding material yards. The obtained samples of boulders and fillers were sent to the laboratory for physical and mechanical tests, which determined the filler's density, internal friction angle, and cohesion. After the tests, fillers from different sources were classified into various filler specifications according to particle size range and material type. Each filler specification was associated with corresponding test index values, and all specifications were summarized to form the preset filler types.

[0044] For the adjacent pile area, the wave flow parameters and the total normal thickness of the subgrade bed are read. The wave flow parameters and the total normal thickness of the subgrade bed are compared one by one with all the filler specifications in the preset filler type. Filler specifications that meet the mechanical stability conditions are selected. The specific weight of the filler stones, the internal friction angle, and the cohesion of the selected filler stones together constitute the filler parameters for the adjacent pile area. For the leading edge area, the wave flow parameters are read. The wave flow parameters are compared one by one with all the filler specifications in the preset filler type. Filler specifications that meet the erosion resistance conditions are selected. The specific weight of the filler stones, the internal friction angle, and the cohesion of the selected filler stones together constitute the filler parameters for the leading edge area.

[0045] In this embodiment, based on the wave flow parameters, slope gradient, and final normal boundary in the normal graded geometric parameters of the normal graded cross-section data, the stable weight of the retaining blocks corresponding to the filler parameters in the leading edge zone is calculated according to the erosion stability relationship of the boulders. The gradation of the retaining blocks is then determined based on this stable weight and the final normal boundary. The erosion stability relationship of the boulders is solved using the Hudson formula to determine the stable weight. The formula for calculating the stable weight is as follows: In the formula, This indicates the stable weight of the footrest stones. This indicates the specific weight of the filler stones. Indicates the density of seawater. Indicates the wave height value. Represents the empirical coefficient; Among them, the seawater specific gravity is obtained by measuring the density of seawater samples collected on-site and multiplying the density by the gravitational acceleration; the wave height value is obtained by on-site monitoring with wave observation equipment; the empirical coefficient is the rock stability coefficient, which is obtained by referring to the coefficient table given in the relevant coastal engineering specifications based on the slope of the dike, the shape of the rocks and the wave action conditions.

[0046] After the stable weight is determined, the corresponding stone particle size range is matched according to the stable weight. Combined with the spatial constraint conditions of the final normal boundary, the stone specifications that meet the particle size requirements are selected, and the gradation of the foot protection stones is determined.

[0047] The defined range of the leading edge zone along the normal direction of the typical design section is read, and the defined range is corrected in combination with wave and current parameters to obtain the toe protection width. The defined range of the leading edge zone includes the starting and ending coordinates along the normal direction of the typical design section, and the difference between the starting and ending coordinates is recorded as the initial width. The correction operation adjusts the initial width by increasing or decreasing it according to the wave height and flow velocity values. The larger the wave height value, the larger the increase in the initial width; the larger the flow velocity value, the larger the increase in the initial width. After the adjustment is completed, the corrected width value is obtained, which is the toe protection width.

[0048] The parameters of the fill material in the adjacent pile area, the parameters of the fill material in the front edge area, as well as the gradation of the riprap and the width of the toe protection, are associated and integrated with the corresponding normal grading levels. In other words, the parameters of the fill material in the adjacent pile area, the parameters of the fill material in the front edge area, the gradation of the riprap and the width of the toe protection are established with the normal grading levels one by one, and the design parameters of the zonal fill material are output.

[0049] Table 1: Grading Statistics of Footwall Stones It should be noted that there is a definite particle size correspondence between the stable weight of the toe protection stones and their gradation. To verify the rationality of the Hudson formula back-calculation results under different wave height conditions, the final-stage normal boundary was selected as the constraint condition, and the slope was fixed at a certain angle. Set wave height values ​​at equal intervals and calculate the corresponding stable weight and matching particle size of the foot protection stones one by one.

[0050] Please see Figure 2 , Figure 2 This is a graph showing the relationship between the stable weight of the foot protection stones and the matching particle size as a function of wave height in this embodiment.

[0051] Based on the 15 sets of data shown in Table 1, combined with Figure 2It can be seen that as the wave height value increases, the stable weight of the toe protection stones shows a rapid increasing trend proportional to H³, and the matching particle size also increases accordingly. When the wave height value is at a low level (such as serial numbers 1~6, H=1.0~2.0m), the stable weight is less than 0.5t, corresponding to a particle size of 0.24~0.44m, at which point conventional bottom protection stone specifications can be used. When the wave height value increases to a medium level (such as serial numbers 7~11, H=2.2~3.0m), the stable weight reaches 0.57~1.46t, corresponding to a particle size of 0.47~ For a wave height of 0.60m, large-sized boulders are required. When the wave height increases further to a higher level (e.g., serial numbers 12-15, H=3.2-3.8m), the stable weight reaches 1.77-2.96t, corresponding to a particle size of 0.63-0.72m. At this point, large boulders or artificial blocks are required to ensure that the leading edge zone is not eroded or damaged. The above data variation patterns verify that the Hudson formula used in this invention can effectively and reasonably back-calculate the gradation of the boulders used for the toe protection, providing a reliable basis for determining the filling parameters and classifying the stability of the leading edge zone.

[0052] S4. Based on the normal graded geometric parameters and the zoned filler design parameters, calculate the sliding force step by step along the tangential direction of the slope. Based on the sliding force, calculate the tangential anti-sliding safety factor and the normal shear safety factor, and output the graded stability judgment result.

[0053] In this embodiment, the normal filling thickness, step lateral recess dimension, and corresponding zone of each level are extracted from the normal graded geometric parameters. The specific weight of the filler stones in the corresponding zone is matched with the design parameters of the zoned filler to obtain graded specific weight data. The normal filling thickness, step lateral recess dimension, and zone identifier recorded in the normal graded geometric parameters are read one by one for each level. The zone identifier is either the adjacent pile area or the front edge area. The specific weight of the filler stones corresponding to the same zone is found in the design parameters of the zoned filler according to the zone identifier. The normal filling thickness, step lateral recess dimension, zone identifier, and the found specific weight of the filler stones of each level are combined to form graded specific weight data.

[0054] Calculate the volume of fill material per unit width for each subgrade bed under a typical design cross-section. Multiply the volume of fill material per unit width by the corresponding density to obtain the self-weight of each subgrade bed. Specifically, for each subgrade bed, the calculation operation reads the normal filling thickness and the lateral step-in dimension. Multiply the normal filling thickness and the lateral step-in dimension by the step-in dimension to obtain the single-level cross-sectional area. Take the unit width along the direction perpendicular to the typical design cross-section, and multiply the single-level cross-sectional area by the unit width to obtain the volume of fill material per unit width for that subgrade bed.

[0055] Multiply the self-weight of each level of subgrade by the sine value of the slope gradient in the normal graded cross-sectional data to obtain the sliding force of each level of subgrade along the tangential direction of the slope.

[0056] In this embodiment, the internal friction angle and cohesion of each packing in the partitioned packing design parameters are obtained. Combined with the sliding force and the slope ratio of the exposed side slope of the adjacent steps of the corresponding grade, the anti-slip force along the tangential direction of the slope surface of each grade is calculated. The tangential anti-slip safety factor is obtained by dividing the anti-slip force along the tangential direction of the slope surface of each grade by the corresponding sliding force. The formula for calculating anti-slip force is: In the formula, This represents the anti-sliding force at each level along the tangential direction of the slope. Indicates the self-weight of each level of the subgrade; Indicates the internal friction angle of the packing; Indicates cohesion. This represents the lateral contact area of ​​the step under a single width condition, obtained by multiplying the lateral indentation of the step by the unit width. This formula is based on the Mohr-Coulomb shear strength theory. In the tangential calculation along the slope, the self-weight of the subgrade is decomposed into a normal component perpendicular to the slope. This normal component is multiplied by the tangent of the internal friction angle of the fill material to calculate the frictional resistance generated by the fill material. Simultaneously, the cohesion is multiplied by the lateral contact area of ​​the step to calculate the bond resistance between the fill materials. Adding these two resistances conforms to the physical law in geotechnical mechanics that the total shear force is composed of both friction and cohesion, thus reasonably yielding the tangential anti-sliding force.

[0057] The self-weight of each level of subgrade bed is decomposed into normal components according to the slope. The normal component, the corresponding normal filling thickness, the internal friction angle of the filling material, and the cohesion are combined to calculate the normal shear force per unit width. The ratio of the normal shear force per unit width to the normal component is used as the normal shear safety factor.

[0058] The formula for calculating the resultant shear force in the normal direction of a single width is as follows: In the formula, Indicates the resultant shear force in the normal direction of a single width. The normal component is represented here. It should be noted that this embodiment is based on a unit width condition; the normal cross-sectional area is obtained by multiplying the normal fill thickness by the unit width, and the normal stress is obtained by dividing the normal component by the cross-sectional area. According to the Mohr-Coulomb criterion, the normal shear strength is the sum of the cohesion and the normal stress multiplied by the tangent of the internal friction angle. Multiplying the normal shear strength by the normal cross-sectional area yields the resultant normal shear force per unit width. Among them, cohesion term For the bond resistance of a single-width normal section, the friction term The frictional resistance generated by the normal stress, both of which are resultant forces per unit width, and the normal component. The dimensions are unified as force / length. Therefore, the normal shear safety factor obtained by the normal component and the resultant normal shear force of a single width is a dimensionless ratio, which is used to evaluate the shear reserve of the normal section.

[0059] Preset tangential anti-slip thresholds and preset normal shear thresholds are set based on the stress characteristics and stability analysis requirements of the sloping normal graded artificial subgrade. During service, the sloping normal graded artificial subgrade needs to resist loads such as waves and water flow. Both the tangential anti-slip safety factor and the normal shear safety factor must be greater than 1 to meet the basic stability conditions. Combining the characteristics of underwater subgrade filler and the stress characteristics of the graded structure, the corresponding minimum allowable values ​​of the safety factors are selected as the preset tangential anti-slip thresholds and preset normal shear thresholds according to the engineering needs, so as to provide sufficient safety reserves and avoid subgrade slippage or shear failure.

[0060] The tangential anti-slip safety factor and normal shear safety factor for each normal grade are compared with the corresponding preset tangential anti-slip threshold and preset normal shear threshold. If the tangential anti-slip safety factor of any first-level normal grade is greater than or equal to the preset tangential anti-slip threshold, and the normal shear safety factor is greater than or equal to the preset normal shear threshold, the current-level subgrade is determined to be stable, the stable state of the current-level subgrade is marked as stable, and the current-level normal grade, tangential anti-slip safety factor and normal shear safety factor are recorded. If the tangential anti-slip safety factor of any first-level normal grade is less than the preset tangential anti-slip threshold, or the normal shear safety factor is less than the preset normal shear threshold, the current grade of the subgrade is determined to be unstable, the stable state of the current grade of the subgrade is marked as unstable, and the current grade of normal grade, tangential anti-slip safety factor and normal shear safety factor are recorded. By summarizing the determination information of each level of normal direction classification, the classification stability determination result is obtained.

[0061] S5. Using the local coordinate system as the kernel, geometric layout and parameter association are performed on the normal graded cross section data, normal graded geometric parameters, zoned filler design parameters and graded stability judgment results, and a three-dimensional parameterized subgrade primitive file is output.

[0062] In this embodiment, using the local coordinate system as a reference, the typical design sections with longitudinal station numbers in the normal graded section data are arranged as control lines along the local coordinate system to obtain a section control line set. Specifically, the spatial position of each typical design section is determined sequentially according to the longitudinal station number value in the longitudinal coordinate axis direction of the local coordinate system. The located typical design sections are used as control lines, and all control lines are arranged in the order of longitudinal station numbers to form a section control line set.

[0063] Based on the local coordinate system, starting from the front profile of the cross section, along the normal direction of the typical design cross section, the normal filling thickness of each level is superimposed in sequence. Combined with the lateral indentation of the step, the horizontal offset is calculated, and the inner and outer boundary coordinates of each step are obtained, which are the level boundary positions.

[0064] Specifically, the coordinates of the leading edge contour of the cross section and the normal direction of the typical design cross section are read. Starting from the leading edge contour of the cross section, the normal filling thickness is accumulated layer by layer along the positive direction of the normal of the typical design cross section. The accumulated result determines the coordinate position of each step in the normal direction. In the horizontal plane, the horizontal position of the inner boundary coordinate of the current level is used as the reference. It is added to the lateral indentation dimension of the step to obtain the horizontal position of the outer boundary coordinate. Conversely, the inner boundary coordinate is obtained by subtracting the indentation dimension from the outer boundary coordinate. The inner boundary coordinate of the first level is determined by accumulating the first level normal filling thickness along the normal direction of the leading edge contour. The inner boundary coordinates of subsequent levels are directly taken from the outer boundary coordinate of the previous level.

[0065] Based on the normal filling thickness at each level, the lateral indentation dimension of the steps, and the position of the grade boundary, the cross-sectional control line set is continuously laid out and surface fitted along the longitudinal direction of the subgrade, and the graded structural morphology of each level is constructed layer by layer to obtain the complete three-dimensional geometric structure of the subgrade.

[0066] Specifically, the layout operation refers to inserting intermediate sections at preset intervals between two adjacent typical design sections with longitudinal station numbers along the longitudinal direction of the subgrade. The grade boundary positions of the intermediate sections are obtained by linear interpolation of the grade boundary positions of adjacent sections. The surface fitting operation connects the inner boundary coordinates of the same step on all sections to form an inner surface, and connects the outer boundary coordinates to form an outer surface. The layer-by-layer construction operation starts from the bottom of the subgrade and repeats the layout and surface fitting for each step to form the graded normal structure of each level. After all levels are constructed, the graded normal structures of each level are combined to obtain the complete three-dimensional geometric structure of the subgrade.

[0067] The normal graded cross-sectional data, normal graded geometric parameters, zoned filling design parameters, and graded stability judgment results are correlated and mapped to the three-dimensional geometry of the subgrade, outputting a three-dimensional parametric subgrade primitive file. Specifically, the geometric entities of each step in the three-dimensional geometry of the subgrade are read, and the normal filling thickness, step lateral indentation dimension, and exposed slope ratio of adjacent steps in the normal graded geometric parameters are bound to the geometric entity attributes. The unit weight of filling stones, internal friction angle, cohesion, toe stone gradation, and toe width in the zoned filling design parameters are bound to the geometric entity attributes. The stability state marker, tangential anti-sliding safety factor, and normal shear safety factor in the graded stability judgment results are bound to the geometric entity attributes. The longitudinal station number, slope gradient, and bedrock slope elevation in the normal graded cross-sectional data are bound to the overall attributes of the three-dimensional geometry of the subgrade, completing the correlation mapping.

[0068] The above formulas are all dimensionless calculations. The formulas are derived from software simulations based on a large amount of collected data to obtain the most recent real-world results. The preset parameters in the formulas are set by those skilled in the art according to the actual situation.

[0069] The above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any other combination thereof. When implemented in software, the above embodiments can be implemented, in whole or in part, as a computer program product. Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution.

[0070] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment, depending on actual needs.

[0071] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

Claims

1. A design method for a sloping, normal-graded artificial subgrade structure, characterized in that, The specific steps include: S1. Acquire underwater bedrock topographic data and control boundary data, fit the elevation point cloud in the underwater bedrock topographic data to generate a continuous bedrock slope surface, extract typical design sections based on the control boundary data, establish a local coordinate system with the normal of the typical design section as the grading reference axis, and output normal graded section data. S2. Determine the normal grade level based on the slope gradient in the normal grade section data, and couple the solution of the normal filling thickness, step lateral indentation dimension and exposed slope ratio of adjacent steps for each grade of subgrade to obtain the normal grade geometric parameters. S3. Extract the front profile of the cross section from the normal graded cross section data, divide the adjacent pile area and the front profile according to the front profile, map the filling type of the adjacent pile area and the front profile, combine the wave flow parameters and slope in the normal graded cross section data, back calculate the toe protection block gradation and toe protection width for the front profile, and output the partitioned filling design parameters including the filling parameters of the adjacent pile area and the filling parameters of the front profile. S4. Based on the normal graded geometric parameters and the zoned fill design parameters, calculate the sliding force step by step along the tangential direction of the slope, calculate the tangential anti-sliding safety factor and the normal shear safety factor based on the sliding force, and output the graded stability judgment result. S5. Using the local coordinate system as the kernel, geometric layout and parameter association are performed on the normal graded cross section data, normal graded geometric parameters, zoned filler design parameters and graded stability judgment results, and a three-dimensional parameterized subgrade primitive file is output.

2. The design method for a sloping, normal-graded artificial subgrade structure according to claim 1, characterized in that: The elevation point cloud in the underwater bedrock topographic data is fitted to generate a continuous bedrock slope surface. The specific steps are as follows: Read the elevation point cloud from the underwater bedrock topographic data, remove outlier points in the elevation point cloud, and output standard elevation point cloud data; The Kriging interpolation algorithm is used to perform grid fitting on standard elevation point cloud data, and the initial slope fitting surface is output. The tangent plane is calculated for each grid patch in the initial slope fitting surface to obtain the tangent plane of the grid patch, and the corresponding normal vector is determined according to the tangent plane. The normal vector is then bound to each grid patch to form a normal attribute fitting surface. The leading edge positioning information in the control boundary data is projected onto the normal attribute fitting surface to obtain the leading edge clipping line. The normal attribute fitting surface is clipped along the leading edge clipping line to form a continuous bedrock slope surface.

3. The method for designing a sloping, normal-graded artificial subgrade structure according to claim 2, characterized in that: Based on the control boundary data, typical design sections are extracted. A local coordinate system is established with the normal of the typical design section as the hierarchical reference axis. The normal hierarchical section data is then output. The specific steps are as follows: Projection analysis is performed on the leading edge positioning information in the control boundary data to extract slope change feature points. The slope change feature points in the continuous bedrock slope surface are used as cutting positions, and supplementary cutting positions are set between adjacent cutting positions at a preset interval. The continuous bedrock slope surface is vertically cut according to the cutting position and the supplementary cutting position to obtain a set of candidate sections; Each cross section in the candidate cross section set is labeled with its corresponding longitudinal station number and defined as a typical design cross section; The normal vectors of each grid patch are extracted from the typical design section with station numbers. The normal vectors of each grid patch are averaged and fitted to determine the normal of the typical design section. A local coordinate system is established using the slope tangent in the typical design section as the auxiliary axis and the normal of the typical design section as the graded reference axis. The local coordinate system is then bound to the typical design section to form a coordinate typical design section. According to the local coordinate system, the corresponding slope gradient, bedrock elevation, section front profile, wave flow parameters and longitudinal station number are extracted from the typical design section of the coordinate system and integrated to form normal graded section data.

4. The design method for a sloping, normal-graded artificial subgrade structure according to claim 1, characterized in that: The normal grade level is determined based on the slope gradient in the normal grade cross-sectional data, and the normal filling thickness, lateral indentation dimension of the step, and slope ratio of the exposed side slope of adjacent steps of each grade subgrade are coupled and solved to obtain the normal grade geometric parameters. The specific steps are as follows: Read the slope gradient from the normal graded cross section data, match the slope gradient according to the preset slope graded interval, and obtain the normal graded level. Extract the control elevation of the top surface of the subgrade from the control boundary data, and calculate the vertical elevation difference with the bedrock slope elevation in the normal graded section data. Determine the total normal thickness of the subgrade along the normal direction of the typical design section based on the vertical elevation difference and the slope gradient. The total normal thickness of the subgrade is discretized into normal filling thicknesses of each level according to the normal grade. Based on the normal filling thickness, the lateral recess dimension of the corresponding step and the slope ratio of the exposed side slope of the adjacent step are determined. The lateral inward dimensions of the steps, the slope ratio of the exposed side slope of adjacent steps, and the normal filling thickness at each level are summarized, and the normal graded geometric parameters are output.

5. The design method for a sloping, normal-graded artificial subgrade structure according to claim 4, characterized in that: Extract the profile of the leading edge of the cross section from the normal graded cross section data, and divide the adjacent pile area and the leading edge area according to the profile of the leading edge of the cross section. The specific steps are as follows: Extract the local coordinates of the front profile of the cross section in the bound local coordinate system from the normal graded cross section data; The leading edge zone is delineated by extending a predetermined distance along the normal of the typical design section towards the sea using local coordinates, and the adjacent pile zone is delineated along the normal of the typical design section towards the land to the control elevation of the top surface of the foundation bed.

6. The design method for a sloping, normal-graded artificial subgrade structure according to claim 5, characterized in that: Mapping the fill type between the adjacent pile zone and the leading edge zone, and combining the wave flow parameters and slope gradient in the normal graded cross-sectional data, back-calculating the toe protection riprap gradation and toe protection width for the leading edge zone, outputting zoned fill design parameters including fill parameters for the adjacent pile zone and the leading edge zone. The specific steps are as follows: Based on the preset filling type, the filling type matching was carried out for the adjacent pile area and the front edge area to determine the filling parameters of the adjacent pile area and the front edge area. Based on the wave flow parameters, slope gradient, and final normal boundary in the normal graded geometric parameters of the normal graded cross section data, the stable weight of the toe stone corresponding to the fill parameters in the front zone is calculated according to the erosion stability relationship of the boulders, and the gradation of the toe stone is determined based on the stable weight and the final normal boundary. The defined range along the normal direction of the typical design section of the leading edge area is read, and the defined range is corrected in combination with wave and current parameters to obtain the toe width; The parameters of the fill material in the adjacent pile area, the parameters of the fill material in the leading edge area, as well as the gradation of the toe protection boulders and the width of the toe protection, are associated and integrated with the corresponding normal grading levels to output the design parameters of the zonal fill material.

7. The method for designing a sloping, normal-graded artificial subgrade structure according to claim 4, characterized in that: Based on the normal graded geometric parameters and the zoned filler design parameters, the sliding force is calculated step by step along the tangential direction of the slope. The specific steps are as follows: Extract the normal filling thickness, step lateral indentation dimension and corresponding zone of each level from the normal graded geometric parameters, and match the fill stone unit weight of the corresponding zone in the zone fill design parameters to obtain graded unit weight data. Calculate the volume of filler per unit width for each level of the subgrade under a typical design section, and multiply the volume of filler per unit width by the corresponding specific weight to obtain the self-weight of each level of the subgrade. Multiply the self-weight of each level of subgrade by the sine value of the slope gradient in the normal graded cross-sectional data to obtain the sliding force of each level of subgrade along the tangential direction of the slope.

8. The design method for a sloping, normal-graded artificial subgrade structure according to claim 7, characterized in that: Based on the sliding force statistics of the tangential anti-slip safety factor and the normal shear safety factor, the graded stability judgment result is output. The specific steps are as follows: Obtain the internal friction angle and cohesion of each packing in the design parameters of the partitioned packing. Combine the sliding force and the slope ratio of the exposed side slope of the adjacent steps of the corresponding grade to calculate the anti-sliding force along the tangential direction of the slope for each grade. The tangential anti-slip safety factor is obtained by dividing the anti-slip force along the tangential direction of the slope at each level by the corresponding sliding force. The self-weight of each level of subgrade bed is decomposed into normal components according to the slope. The normal component, the corresponding normal filling thickness, the internal friction angle of the filling material, and the cohesion are combined to calculate the normal shear force per unit width. The ratio of the normal shear force per unit width to the normal component is used as the normal shear safety factor. Preset tangential anti-slip threshold and preset normal shear threshold; The tangential anti-slip safety factor and normal shear safety factor for each normal grade are compared with the corresponding preset tangential anti-slip threshold and preset normal shear threshold. If the tangential anti-slip safety factor of any first-level normal grade is greater than or equal to the preset tangential anti-slip threshold, and the normal shear safety factor is greater than or equal to the preset normal shear threshold, the current-level subgrade is determined to be stable. If the tangential anti-slip safety factor of any first-level normal grade is less than the preset tangential anti-slip threshold, or the normal shear safety factor is less than the preset normal shear threshold, the current-level subgrade is determined to be unstable. By summarizing the determination information of each level of normal direction classification, the classification stability determination result is obtained.

9. The design method for a sloping, normal-graded artificial subgrade structure according to claim 1, characterized in that: Using a local coordinate system as the core, the normal graded cross-sectional data, normal graded geometric parameters, zoned filler design parameters, and graded stability judgment results are geometrically laid out and parameterized, outputting a three-dimensional parametric subgrade primitive file. The specific steps are as follows: Using the local coordinate system as a reference, the typical design sections with longitudinal station numbers in the normal graded section data are arranged as control lines along the local coordinate system to obtain the section control line set. Based on the local coordinate system, starting from the front profile of the cross section, along the normal direction of the typical design cross section, the normal filling thickness of each level is superimposed in sequence. Combined with the lateral indentation of the step, the horizontal offset is calculated, and the inner and outer boundary coordinates of each step are obtained, which are the level boundary positions. According to the normal filling thickness of each level, the lateral indentation size of the steps, and the position of the grade boundary, the cross-section control line set is continuously laid out and surface fitted along the longitudinal direction of the subgrade, and the graded structure of each level of normal is constructed layer by layer to obtain the complete three-dimensional geometric structure of the subgrade. The normal graded cross-sectional data, normal graded geometric parameters, zoned filler design parameters, and graded stability determination results are correlated and mapped to the three-dimensional geometry of the subgrade, and a three-dimensional parametric subgrade primitive file is output.

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