Method for calculating and counting mileage and distance corresponding to linear engineering sensitive points

Abstract

The invention relates to the technical field of CAD (computer-aided design), and discloses a linear engineering sensitive point corresponding mileage and distance calculation statistical method, which comprises the following steps of: S101, creating a layer and generating a closed polyline based on character coordinates and character contents in a building so as to quickly model the building; s102, reading plane data of a line center line and sensitive points, converting the line center line into a matrix form containing coordinates, convexity, corresponding stake marks and curvature of each point, and converting the sensitive point data into a matrix form containing coordinates and radius; s103, calculating a projection relation between the sensitive point and the line center line so as to determine a mileage range, an orientation relation, a minimum distance and a curve radius of the sensitive point; and step S104, based on the calculation result of the step S103, counting the number of buildings, the starting and ending stake numbers, the nearest distance and the curve radius included in each sensitive point. From the whole project period, the method can greatly improve the working efficiency and accuracy.

Description

Technical Field

[0001] This invention relates to the field of CAD technology, and in particular to a method for calculating and statistically analyzing the mileage and distance corresponding to sensitive points in linear engineering. Background Technology

[0002] The investigation of protected targets is the foundation of environmental impact assessment. Environmental impact assessment guidelines require a table showing the spatial relationship between the protected targets and the construction project within the assessment scope.

[0003] For linear engineering projects, the spatial relationship of protected targets includes mileage range, positional relationship (left / right), and nearest horizontal distance. Taking rail transit and municipal engineering projects as examples, the noise assessment range is generally within 200 meters on both sides of the centerline / edgeline of the line. A 30-kilometer-long project often involves nearly a hundred sensitive points and thousands of buildings. During the design phase, the project is not stable, and the alignment (lateral offset, start and end point adjustment) often undergoes dozens of adjustments. Each version of the plan requires the environmental impact assessment unit to re-examine the spatial relationship, a tedious and heavy task, and errors and omissions are inevitable when manually compiling statistics.

[0004] In environmental impact assessments, sensitive points around the route can be considered fixed (only involving additions and subtractions, not displacements). Therefore, modeling sensitive points is a one-time process that benefits the entire project lifecycle (design, construction, acceptance, and operation). Summary of the Invention

[0005] This invention proposes a method for calculating and statistically analyzing the mileage and distance corresponding to sensitive points in linear engineering projects. The purpose of this invention is to calculate and statistically analyze the mileage range, location, and nearest distance of sensitive points by inputting the planar information of the railway line and the planar information of the sensitive points into a calculation system. The method for calculating and statistically analyzing the mileage and distance corresponding to sensitive points in linear engineering projects includes the following steps: Step S101: Based on the text coordinates and text content within the building, create layers and generate closed polylines for rapid building modeling; Step S102: Read the planar data of the line centerline and sensitive points, convert the line centerline into a matrix form containing the coordinates, convexity, corresponding station number and curvature of each point, and convert the sensitive point data into a matrix form containing coordinates and radius; Step S103: Calculate the projection relationship between the sensitive point and the center line of the line to determine the mileage range, orientation relationship, minimum distance and curve radius of the sensitive point; Step S104: Based on the calculation results of step S103, count the number of buildings, start and end station numbers, nearest distance and curve radius of each sensitive point.

[0006] The present invention has the following beneficial effects: 1. This invention provides a rapid building modeling method based on CAD.

[0007] 2. Implement calculations and statistics on mileage range, shortest distance, and curve radius for linear engineering.

[0008] 3. The most time-consuming part of this method is modeling the sensitive points. However, once a model is created, it is useful throughout the entire design and construction process and can also be used for subsequent 3D modeling. From the perspective of the entire project cycle, this method can greatly improve work efficiency and accuracy. Attached Figure Description

[0009] Figure 1 This is a flowchart of a statistical method for calculating the mileage and distance corresponding to sensitive points in linear engineering. Figure 2 It is a typical topographic map; Figure 3 This is a flowchart for rapid building modeling; Figure 4 This is a flowchart of line data preprocessing; Figure 5 This is a flowchart of sensitive data preprocessing; Figure 6 It refers to the positional relationship between a point / circle and a line; Figure 7 It is a schematic diagram showing the positional relationship between buildings (straight lines and arcs) and lines (straight lines and arcs); Figure 8 It allows for quick location of the line position corresponding to sensitive points. Detailed Implementation

[0010] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms “comprising” or “having,” and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0011] In environmental impact assessments, sensitive points around the route can be considered fixed (only involving additions and subtractions, not displacements). Therefore, modeling sensitive points is a one-time process that benefits the entire project lifecycle (design, construction, acceptance, and operation).

[0012] CAD uses vector graphics, requiring only the storage of geometric parameters and relying on mathematical descriptions to depict information such as color, layers, and outlines. Parameters applicable to graphic objects (called primitives) can be accessed via primitive group codes, which can be found in the ENTITIES area of ​​the DXF file. The most commonly used primitives in engineering drawings include: 1. Points (POINT) or Inserted Primitives (INSERT); 2. Circles (CIRCLE); 3. Lines (LINE); 4. Arcs (ARC); 5. Lightweight Polylines (LWPOLYLINE); 6. Text.

[0013] Lightweight polylines, introduced in AutoCAD R14, are the default polyline type in subsequent versions. They feature a more optimized storage structure and are characterized by: 1) lightweight design; 2) two-dimensional limitation (uniform Z-coordinate); and 3) single entity.

[0014] LWPOLYLINE's advantage lies in introducing the concept of convexity, representing straight lines and arcs using the same format. Convexity is a crucial concept in AutoCAD, controlling the magnitude and direction of the arc between two points. ) is defined as the radians contained in an arc ( The tangent of 1 / 4, that is: .

[0015] For ease of understanding, the specific process of the embodiments of the present invention is described below. Please refer to [link / reference]. Figure 1-8 The first embodiment of the method in this invention includes: Step S101: Based on the text coordinates and text content within the building, create layers and generate closed polylines for rapid building modeling; Step S102: Read the planar data of the line centerline and sensitive points, convert the line centerline into a matrix form containing the coordinates, convexity, corresponding station number and curvature of each point, and convert the sensitive point data into a matrix form containing coordinates and radius; Step S103: Calculate the projection relationship between the sensitive point and the center line of the line to determine the mileage range, orientation relationship, minimum distance and curve radius of the sensitive point; Step S104: Based on the calculation results of step S103, count the number of buildings, start and end station numbers, nearest distance and curve radius of each sensitive point.

[0016] In a preferred embodiment of the present invention, step S101 involves rapid building modeling. For example... Figure 2The image shown is a typical topographic map, containing graphic and textual information such as road edges, ground elevations, buildings, and waterways. Buildings are generally represented by closed areas indicating their outlines, with internal text indicating their structure and number of floors, such as "Brick 2", "Concrete 5", "Concrete 11", "6", etc.

[0017] Modeling conventional buildings is typically achieved by extruding a two-dimensional profile along the Z-axis. Therefore, the focus of rapid modeling is on drawing its closed boundaries and setting its height.

[0018] The BOUNDARY command, built into AutoCAD, can be used to create regions or polylines from closed areas. For example... Figure 3 The image shown is a schematic diagram of rapid building modeling: S201. Select the text inside the house; S202. Recognize text and insertion point coordinates; S203. Create / select a layer with "General Prefix" + "Text"; S204. Within this layer, use the text insertion point coordinates as the pick point for BOUNDARY to create a closed polyline; S205. Select and adjust the elevation of polylines in batches by isolating layers.

[0019] In a preferred embodiment of the present invention, step S102 involves reading and converting the planar data of the line centerline and sensitive points. (Planar data for linear engineering) Figure 1 Generally, an urban plane coordinate system (i.e., using X and Y coordinates instead of latitude and longitude) is used, and the unit of measurement for graphics is meters. The exported data needs to be preprocessed.

[0020] Preprocessing of line centerline data. The line centerlines are merged into a single lightweight polyline, i.e., an unclosed polyline with N vertices, denoted as […]. (1≤i≤N).

[0021] When the vertex sequence of a polyline is opposite to the direction of mileage increase, the direction can be reversed using the Pedit command. Alternatively, the direction can be reversed using the following formula: when Sometimes, , , .

[0022] When there is a superior arc in the line ( When this happens, it makes the subsequent series of judgments more complicated. This can be addressed by inserting the midpoint of the arc. The method transforms the line into two inferior arcs.

[0023] In actual engineering projects, due to reasons such as partial rerouting or segmented measurement, there may be a phenomenon where the station numbers are not connected, i.e., a chain break. In this case, the subsequent station numbers should be recalculated starting from the mileage after the chain break (for example: AK1+195=AK1+200 (short chain 5 meters), AK1+200 should be used as the station number corresponding to this point).

[0024] At this point, it is necessary to insert a break point within the existing polyline. The stationing calculation for subsequent vertices begins from this point.

[0025] Within a straight line segment, the break point can be directly inserted. Within the circular arc segment, after inserting the break point, the curve radius remains unchanged, therefore recalculation is required. and ,have: Because it is necessary to calculate and statistically analyze the mileage and corresponding circular curve radius of sensitive points, the N×3 matrix is ​​expanded to N×5. For ease of subsequent statistics, curvature is used as the basis. (reciprocal of radius) ) is used as a parameter, denoted as , which are the station numbers corresponding to each vertex. ,coordinate ,coordinate convexity and curvature .

[0026] Given the starting point pile Or broken chainage marker Then, the station number for each subsequent point can be calculated using the following formula: Straight line segment: curvature .

[0027] Circular curve segment: The curvature is the reciprocal of the curve radius, which can be expressed by convexity. chord length Find the answer.

[0028] Transition curve segments: In engineering drawings, transition curves can be drawn in two ways. The curvature of a transition curve varies with its length. A transition curve can be regarded as an extension of a circular curve (i.e., uniform curvature). Alternatively, the curvature of each point on the transition curve can be approximated using the following method.

[0029] 1) The transition curves commonly used for highways and ramps are spiral curves, which are polylines composed of multiple circular arcs in engineering drawings. The curvature at each point can be easily calculated from the convexity.

[0030] 2) The transition curve commonly used on railways is a cubic parabola. In engineering drawings, it is a polyline composed of multiple straight lines. The curvature can be calculated by the coordinates of two adjacent points.

[0031] Preprocessing of sensitive point data. Sensitive point data may include points, insertions, circles, lines, arcs, and lightweight polylines. To facilitate subsequent data calculations, the sensitive point data is uniformly converted to an N×3 format.

[0032] Points, insertions, and circles can be converted into 1×3 matrices, denoted as... , which are the X value, Y value, and radius, respectively.

[0033] Straight lines and arcs can be converted into 2×3 matrices, denoted as . For a straight line, we have For a circular arc, given the coordinates of the center... ,radius Starting point angle and endpoint angle Then, it can be converted using the following formula: Where mod is the modulo function, that is, when converting from an arc to a polyline, we have .

[0034] Lightweight polylines are M×3 matrices ( When it is a closed polyline, the data is converted into an open polyline by adding a line at the end.

[0035] In a preferred embodiment of the present invention, step S103 involves calculating the mileage range, directional relationship, and relative distance of the sensitive points. Mathematically, this means calculating the sensitive points... and lines The projection relationship.

[0036] when When the sensitive point is a point or a circle, it is denoted as . When the vertical projection corresponding to the center A of the circle is a straight line... When, the projection point is denoted as At that time, the following conditions are met: in, and These represent the length and height of the projection, respectively.

[0037] When the vertical projection corresponding to the center A of the circle is an arc At that time, the following conditions are met: in, For arc The corresponding center coordinates of the circle.

[0038] Sensitive points The corresponding station range is: The determination of direction and closest distance is as follows: 1) When At that time, the orientation is to the left, and the minimum distance is ;2) When At that time, the orientation is to the right, and the minimum distance is ;3) When At that time, the orientation is crossing, and the minimum distance is 0.

[0039] when When the sensitive point is a polyline, the corresponding station number range can be obtained by finding the station number corresponding to each point (ignoring the case where the arc of the sensitive point protrudes along the line direction).

[0040] Determining the closest distance and direction is quite complex, using a straight line... or arc Taking a polyline as an example, this paper introduces how to calculate spatial position in the case of polylines.

[0041] A) When the straight line The projections of the two points lie on the same straight line. When, the location and closest distance are determined as follows: 1) When At that time, the orientation is to the left, and the minimum distance is ;2) When At that time, the orientation is to the right, and the minimum distance is ;3) When At that time, the orientation is crossing, and the minimum distance is 0.

[0042] B) When the straight line The two points are projected onto the same arc. When doing so, the arc should be calculated first. The coordinates of the center of the circle Then determine its line segment Is there a projection on the surface? If so, calculate its coordinates. and find .if If it does not exist, the location and distance determination are the same as in A); The existence, location, and nearest distance are determined as follows: 1) When , and All values ​​are greater than 0, the orientation is to the left, and the minimum distance is... ;2) When , and All values ​​are less than 0, the orientation is to the right, and the minimum distance is... 3) In other cases, the orientation is through, and the minimum distance is 0.

[0043] C) When the arc The projections of the two points lie on the same straight line. When doing so, the arc should be calculated first. The coordinates of the center of the circle Then judge Its online segment Is there a projection on the surface? If so, calculate its coordinates. At this point, make another judgment. In the arc Is there a projection on the surface? If so, calculate its coordinates. and find .if The existence, location, and nearest distance are determined as follows: 1) When , and All values ​​are greater than 0, the orientation is to the left, and the minimum distance is... ;2) When , and All values ​​are less than 0, the orientation is to the right, and the minimum distance is... 3) In other cases, the orientation is through, and the minimum distance is 0.

[0044] D) When the arc The two points are projected onto the same arc. When doing so, the arc should be calculated first. The coordinates of the center of the circle and arc The coordinates of the center of the circle And then find With arc intersection and .if The existence, location, and nearest distance are determined as follows: 1) When , and All values ​​are greater than 0, the orientation is to the left, and the minimum distance is... ;2) When , and All values ​​are less than 0, the orientation is to the right, and the minimum distance is... 3) In other cases, the orientation is through, and the minimum distance is 0.

[0045] In a preferred embodiment of the present invention, step S104 involves: counting the number of buildings, starting and ending station numbers, nearest distance, and curve radius of each sensitive point. Following step S103, the station number, distance, and curvature corresponding to each point within the sensitive point are calculated. Therefore, the mileage range can be obtained by finding the minimum and maximum values, the nearest distance can be obtained by finding the minimum value, and the minimum curve radius can be obtained by finding the maximum value.

[0046] Example 1: Quickly locate the point of chain breakage The information about the broken link includes the coordinates of the broken link. and corresponding mileage Therefore, its approximate location can be quickly determined using its mileage. Assuming that its location can be quickly determined based on the mileage of the link break point and the actual cumulative mileage of the route, it can be located... and between.

[0047] when At that time, there is no dominant arc, and the location of the chain break point has been roughly determined. It can be directly determined through judgment. The value is used to determine the break point. Is it located in and Between. When , ;when , .

[0048] Example 2: Quickly locate the position of the sensitive point Except for a few sensitive points before the starting point and after the ending point, the vast majority of sensitive targets are located on both sides of the route, meaning they have vertical projection points on the route. However, engineering routes are often not straight, and any point outside the route may have multiple vertical projections on the route (e.g., Figure 8 As shown in the diagram, if the wrong location is selected, the spatial location of the sensitive point cannot be accurately reflected. This problem can be solved by traversal. However, in actual engineering, the length of the transition curve segment often exceeds 50%, and in a 20-kilometer project, the number of vertices often exceeds 10,000, requiring a significant amount of time to use traversal.

[0049] This can be achieved by expanding the sensitive points outwards to form a rectangular frame (e.g., Figure 8 As shown), we obtain .when and This indicates that the sensitive point is also within the evaluation range of that section of the line. Faster convergence can be achieved by converging from the start and end points towards the median, with a step size greater than 1.

[0050] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A statistical method for calculating the mileage and distance corresponding to linear engineering sensitive points, characterized in that, The method includes the following steps: Step S101: Based on the text coordinates and text content within the building, create layers and generate closed polylines for rapid building modeling; Step S102: Read the planar data of the line centerline and sensitive points, convert the line centerline into a matrix form containing the coordinates, convexity, corresponding station number and curvature of each point, and convert the sensitive point data into a matrix form containing coordinates and radius; Step S103: Calculate the projection relationship between the sensitive point and the center line of the line to determine the mileage range, orientation relationship, minimum distance and curve radius of the sensitive point; Step S104: Based on the calculation results of step S103, count the number of buildings, start and end station numbers, nearest distance and curve radius of each sensitive point.

2. The method for calculating and statistically analyzing the mileage and distance corresponding to linear engineering sensitive points according to claim 1, characterized in that, The specific steps of step S101 are as follows: Topographic maps include road edges, ground elevations, building and river graphics and text. Buildings are represented by closed areas, and the text inside indicates their structure and number of floors. To create a region or polyline from a closed area using the BOUNDARY command built into CAD: Select the text inside the building; within this layer, use the text's insertion point coordinates as the pick point for BOUNDARY to create a closed polyline; By isolating layers, you can select and adjust the elevation of polylines in batches to quickly model buildings.

3. The method for calculating and statistically analyzing the mileage and distance corresponding to linear engineering sensitive points according to claim 1, characterized in that, Step S102 also includes preprocessing of the line centerline data: Merge the centerlines of the lines into a single lightweight polyline, that is, an unclosed polyline with N vertices, denoted as . Where 1≤i≤N; When the order of the vertices of a polyline is opposite to the direction of mileage increase, use the Pedit command to change the direction; Alternatively, the direction of the line can be reversed using the following formula: when Sometimes, , , .

4. The method for calculating and statistically analyzing the mileage and distance corresponding to linear engineering sensitive points according to claim 3, characterized in that, In step S102, when a superior arc exists in the line, that is... By inserting the midpoint of the arc The method transforms the line into two minor arcs, as shown in the following formula: 。 5. The method for calculating and statistically analyzing the mileage and distance corresponding to linear engineering sensitive points according to claim 4, characterized in that, When a chainage break occurs, subsequent chainages should be recalculated starting from the mileage after the chainage break. Insert a break point within the existing multi-segment line. The stationing calculation for subsequent vertices begins from this point; Within a straight line segment, the break point can be directly inserted. Within the arc segment, after inserting the break point, the curve radius remains unchanged; recalculate. and ,have: 。 6. The method for calculating and statistically analyzing the mileage and distance corresponding to linear engineering sensitive points according to claim 1, characterized in that, The calculation and statistical analysis of the mileage and corresponding circular curve radius of the sensitive points include: Expand the N×3 matrix to N×5, with curvature As a parameter, denoted as curvature equal to the reciprocal of the radius ; The corresponding station number for each vertex ,coordinate ,coordinate convexity and curvature ; Given the starting point pile Or broken chainage marker Then, the station number for each subsequent point can be calculated using the following formula: Straight line segment: curvature ; Circular curve segment: The curvature is the reciprocal of the curve radius, which can be expressed by convexity. chord length Find it; Transition curve segment: 1) The transition curves commonly used for highways and ramps are spirals, which are polylines composed of multiple circular arcs; the curvature at each point can be determined by the convexity. 2) The transition curves commonly used on railways are cubic parabolic curves, which are polylines composed of multiple straight lines. The curvature is determined by the coordinates of two adjacent points. 。 7. The method for calculating and statistically analyzing the mileage and distance corresponding to linear engineering sensitive points according to claim 1, characterized in that, The preprocessing of the sensitive point data specifically involves: Convert the data of sensitive points into a unified N×3 format; If the sensitive points are points, insertions, and circles, then it is converted into a 1×3 matrix, denoted as . , which are the X value, Y value, and radius, respectively; If the sensitive points are lines and arcs, then convert them into a 2×3 matrix, denoted as . ; For a straight line, we have ; For a circular arc, given the coordinates of the center... ,radius Starting point angle and endpoint angle Then, it can be converted using the following formula: Where mod is the modulo function, that is, when converting from an arc to a polyline, we have ; Lightweight polylines are M×3 matrices ( When it is a closed polyline, the data is converted into an open polyline by adding a line at the end.

8. The method for calculating and statistically analyzing the mileage and distance corresponding to linear engineering sensitive points according to claim 1, characterized in that, In step S103: Sensitive points are either dots or circles, denoted as... When the vertical projection corresponding to the center A of the circle is a straight line When, the projection point is denoted as At that time, the following conditions are met: in, and These are the length and height of the projection, respectively; When the vertical projection corresponding to the center A of the circle is an arc At that time, the following conditions are met: in, For arc The corresponding center coordinates; Sensitive points The corresponding station range is: The determination of direction and closest distance is as follows: 1) When At that time, the orientation is to the left, and the minimum distance is ;2) When At that time, the orientation is to the right, and the minimum distance is ;3) When At that time, the orientation is crossing, and the minimum distance is 0.

9. The method for calculating and statistically analyzing the mileage and distance corresponding to linear engineering sensitive points according to claim 1, characterized in that, In step S103, when the sensitive point is a polyline: The corresponding station number range can be obtained by calculating the station number corresponding to each point. The methods for determining the orientation relationship and minimum distance are as follows: A) When the straight line The projections of the two points lie on the same straight line. When, the location and closest distance are determined as follows: 1) When At that time, the orientation is to the left, and the minimum distance is ;2) When At that time, the orientation is to the right, and the minimum distance is ;3) When At that time, the orientation is crossing, and the minimum distance is 0; B) When the straight line The two points are projected onto the same arc. hour: First find the arc The coordinates of the center of the circle Then determine its line segment Is there a projection on the surface? If so, calculate its coordinates. and find ;if If it does not exist, the location and distance determination are the same as in A); The existence, location, and nearest distance are determined as follows: 1) When , and All values ​​are greater than 0, the orientation is to the left, and the minimum distance is... ;2) When , and All values ​​are less than 0, the orientation is to the right, and the minimum distance is... 3) In other cases, the orientation is through, and the minimum distance is 0; C) When the arc The projections of the two points lie on the same straight line. hour: First find the arc The coordinates of the center of the circle Then judge Its online segment Is there a projection on the surface? If so, calculate its coordinates. At this point, make another judgment. In the arc Is there a projection on the surface? If so, calculate its coordinates. and find ;if The existence, location, and nearest distance are determined as follows: 1) When , and All values ​​are greater than 0, the orientation is to the left, and the minimum distance is... ;2) When , and All values ​​are less than 0, the orientation is to the right, and the minimum distance is... 3) In other cases, the orientation is through, and the minimum distance is 0; D) When the arc The two points are projected onto the same arc. hour: First find the arc The coordinates of the center of the circle and arc The coordinates of the center of the circle And then find With arc intersection and ;if The existence, location, and nearest distance are determined as follows: 1) When , and All values ​​are greater than 0, the orientation is to the left, and the minimum distance is... ;2) When , and All values ​​are less than 0, the orientation is to the right, and the minimum distance is... 3) In other cases, the orientation is through, and the minimum distance is 0.

10. The method for calculating and statistically analyzing the mileage and distance corresponding to linear engineering sensitive points according to claim 1, characterized in that, Step S104 specifically involves: Calculate the number of buildings, start and end station numbers, nearest distance, and curve radius for each sensitive point; After step S103, the station number, distance, and curvature corresponding to each point within the sensitive point are calculated; The mileage range is obtained by finding the minimum and maximum values, the shortest distance is obtained by finding the minimum value, and the minimum curve radius is obtained by finding the maximum value.

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