A railway subgrade design method based on BIM technology

Abstract

The application discloses a railway roadbed design method based on BIM technology, and comprises the following steps: reading a line information model to generate a roadbed work point line position; creating a roadbed work point shoulder line considering curve widening; dividing a road embankment section and a road cutting section in a work point based on three-dimensional terrain data; drawing a roadbed, a road cutting side ditch, a boundary range and a slope cross section contour line of layered fillers; generating a road embankment model, a road cutting model, a road cutting side ditch model and a slope model according to the shoulder line and the cross section contour line; cutting the road embankment model and the road cutting slope model below the road embankment base bed and the terrain; and completing railway roadbed design. The application realizes forward design of a railway roadbed BIM model, automatically completes section division of the road embankment and the road cutting in the roadbed work point by reading three-dimensional line data and terrain data, creates the road embankment model and the road cutting model by using a pre-drawn roadbed and side ditch contour, and realizes automatic calculation of different filler volumes.

Description

Technical Field

[0001] This invention belongs to the field of three-dimensional modeling and design, specifically relating to a railway roadbed design method based on BIM technology. Background Technology

[0002] Two-dimensional design of railway subgrade engineering commonly employs the cross-section design method. This method can only reflect the specific details of scattered cross-sections, failing to accurately describe the changing trends between cross-sections and lacking a holistic perspective. When calculating quantities, especially the earthwork volume of the subgrade body, estimations based on cross-section data with large intervals often deviate from the actual project conditions. Utilizing measured three-dimensional topographic data for BIM design of the subgrade body can accurately simulate the actual situation in three-dimensional space. Furthermore, leveraging the visualization advantages of BIM technology facilitates a better understanding of the design intent by all project stakeholders.

[0003] Current domestic BIM design methods for railway subgrade structures, when used in special cases such as ballast railway curves where curve widening is not considered, can lead to discrepancies between the BIM model and the actual site conditions. This makes it impossible to guarantee consistency between the model and the drawings, and thus hinders the effective functioning of railway engineering throughout its entire lifecycle, including design, construction, and management. Summary of the Invention

[0004] This invention is proposed to solve the problems existing in the prior art, and its purpose is to provide a railway roadbed design method based on BIM technology.

[0005] The technical solution of this invention is: a railway roadbed design method based on BIM technology, comprising the following steps: A. Read the route information model and generate the roadbed construction point alignment; B. Create road shoulder lines at roadbed construction points that take into account curve widening; C. Based on three-dimensional terrain data, divide the embankment section and the cutting section within the work site; D. Draw the roadbed structure, cut side ditches and boundary range, and slope cross-sectional outline of the fill layer; E. Generate embankment body model, cut body model, cut side ditch model, and slope model based on shoulder line and cross-section outline; F. The model below the embankment subgrade and the model of the cut slope are trimmed according to the terrain; G. Complete the basic design of the railway track.

[0006] Furthermore, the line information model in step A includes horizontal plane data, vertical profile data, chainage data, railway type, railway grade, design speed, number of lines, and track spacing.

[0007] Furthermore, step A reads the route information model and generates the roadbed construction point alignments. The specific process is as follows: a1. Read the railway line's horizontal and vertical profile data, chainage data, railway type, railway grade, design speed, number of lines, and track spacing; a2. Based on the starting and ending mileages of the roadbed construction points and the chain break number in the chain break data, generate the starting and ending points of the roadbed construction points on the line model; a3. Using the start and end points of the roadbed construction points, the line positions of the roadbed construction points are intercepted on the line model.

[0008] Furthermore, step B involves creating the road shoulder line at the roadbed construction point, taking into account curve widening. This includes the process of generating the road shoulder line, as detailed below: b1. Based on the half-width of the roadbed, the line spacing, and the roadbed surface drainage slope, the alignment of the work site is shifted to both sides; b2. After offsetting to both sides, generate the left and right shoulder lines without considering curve widening.

[0009] Furthermore, step B involves creating the road shoulder line at the roadbed construction point, taking into account curve widening, including the process of widening the road shoulder line. The specific process is as follows: b3. For ballasted railways, when the roadbed construction point is located on a curved section, the railway type, railway grade, design speed, and curve radius are obtained; b4. Widen the left and right shoulder lines obtained in step b2 outside the curve.

[0010] Furthermore, the shoulder widening value should decrease linearly within the transition curve range.

[0011] Furthermore, step C, based on 3D terrain data, divides the embankment and cutting sections within the work site, including determining and dividing the sections. The specific process is as follows: c1. Obtain the intersection points of the left shoulder line, the right shoulder line and the 3D terrain model respectively; c2. Using the intersection points obtained above, divide the shoulder line into multiple segments.

[0012] Furthermore, step C, based on 3D terrain data, divides the work site into embankment and cutting sections, including the division of embankment and cutting sections within the work site. The specific process is as follows: c3. Determine the type of roadbed in the first paragraph, specifically whether it is an embankment paragraph or a cutting paragraph; c4. Add the corresponding attribute values ​​to the shoulder lines of the above paragraphs; c5. Add embankment / cutting attribute values ​​to the shoulder lines of the remaining paragraphs in sequence, with the values ​​being the opposite of those of the previous paragraph, until the last paragraph.

[0013] Furthermore, step D involves drawing the basic road structure, the side ditch and boundary range of the fill layer, and the cross-sectional outline of the slope. The specific process is as follows: Using the left shoulder point, right shoulder point, and midpoint of the roadbed surface as references, draw the outlines of the surface layer, bottom layer, and below layer of the embankment subgrade on both the left and right sides, as well as the surface layer and bottom layer of the cut subgrade.

[0014] Furthermore, step D involves drawing the basic road structure, the side ditch and boundary range of the fill layer, and the cross-sectional outline of the slope. The specific process is as follows: Using the left and right shoulder points as references, draw the side ditches, the boundary range of the side ditches, and the outline of the slopes on both the left and right sides of the road cut.

[0015] The beneficial effects of this invention are as follows: This invention enables forward design of railway subgrade BIM models. By reading three-dimensional line data and terrain data, it automatically completes the segment division of embankments and cuttings within subgrade construction sites. Using pre-drawn subgrade body and side ditch outlines, it creates embankment and cutting body models and realizes automatic calculation of different filler volumes.

[0016] This invention can improve the accuracy of roadbed body BIM design. By using three-dimensional measured terrain to carry out roadbed body BIM design, it effectively overcomes the drawbacks of the two-dimensional cross-section design method, making the design results closer to the actual site conditions and the filling volume calculation more accurate. For ballast railway curve sections, it can widen the roadbed surface on the outside of the curve, ensuring the consistency between the model and the design intent.

[0017] This invention enables rapid adjustment of 3D design results by drawing parametric body contours, facilitating scheme comparison and design changes, and has certain application value. Attached Figure Description

[0018] Figure 1 This is a flowchart of the method of the present invention. Detailed Implementation

[0019] The present invention will now be described in detail with reference to the accompanying drawings and embodiments: like Figure 1 As shown, a railway roadbed design method based on BIM technology includes the following steps: A. Read the route information model and generate the roadbed construction point alignment; B. Create road shoulder lines at roadbed construction points that take into account curve widening; C. Based on three-dimensional terrain data, divide the embankment section and the cutting section within the work site; D. Draw the roadbed structure, cut side ditches and boundary range, and slope cross-sectional outline of the fill layer; E. Generate embankment body model, cut body model, cut side ditch model, and slope model based on shoulder line and cross-section outline; F. The model below the embankment subgrade and the model of the cut slope are trimmed according to the terrain; G. Complete the basic design of the railway track.

[0020] The track information model in step A includes horizontal data, vertical profile data, chainage data, railway type, railway grade, design speed, number of tracks, and track spacing.

[0021] Step A reads the route information model and generates the roadbed construction point alignments. The specific process is as follows: a1. Read the railway line's horizontal and vertical profile data, chainage data, railway type, railway grade, design speed, number of lines, and track spacing; a2. Based on the starting and ending mileages of the roadbed construction points and the chain break number in the chain break data, generate the starting and ending points of the roadbed construction points on the line model; a3. Using the start and end points of the roadbed construction points, the line positions of the roadbed construction points are intercepted on the line model.

[0022] Step B involves creating the shoulder lines at the roadbed construction points that take into account curve widening. This includes the process of generating the shoulder lines, as detailed below: b1. Based on the half-width of the roadbed, the line spacing, and the roadbed surface drainage slope, the alignment of the work site is shifted to both sides; b2. After offsetting to both sides, generate the left and right shoulder lines without considering curve widening.

[0023] Step B involves creating the road shoulder line at the roadbed construction point, taking into account curve widening. This includes the process of widening the road shoulder line, as detailed below: b3. For ballasted railways, when the roadbed construction point is located on a curved section, the railway type, railway grade, design speed, and curve radius are obtained; b4. Widen the left and right shoulder lines obtained in step b2 outside the curve.

[0024] The shoulder widening value should decrease linearly within the transition curve range.

[0025] Step C, based on 3D terrain data, divides the embankment and cutting sections within the work site, including determining and dividing the sections. The specific process is as follows: c1. Obtain the intersection points of the left shoulder line, the right shoulder line and the 3D terrain model respectively; c2. Using the intersection points obtained above, divide the shoulder line into multiple segments.

[0026] Step C, based on 3D terrain data, divides the work site into embankment and cutting sections. The specific process is as follows: c3. Determine the type of roadbed in the first paragraph, specifically whether it is an embankment paragraph or a cutting paragraph; c4. Add the corresponding attribute values ​​to the shoulder lines of the above paragraphs; c5. Add embankment / cutting attribute values ​​to the shoulder lines of the remaining paragraphs in sequence, with the values ​​being the opposite of those of the previous paragraph, until the last paragraph.

[0027] Step D involves drawing the roadbed structure, cut side ditches and their boundaries, and slope cross-sectional outlines for the layered fill material. The specific process is as follows: Using the left shoulder point, right shoulder point, and midpoint of the roadbed surface as references, draw the outlines of the surface layer, bottom layer, and below layer of the embankment subgrade on both the left and right sides, as well as the surface layer and bottom layer of the cut subgrade.

[0028] Step D involves drawing the roadbed structure, cut side ditches and their boundaries, and slope cross-sectional outlines for the layered fill material. The specific process is as follows: Using the left and right shoulder points as references, draw the side ditches, the boundary range of the side ditches, and the outline of the slopes on both the left and right sides of the road cut.

[0029] Specifically, step E generates the embankment body model, cut body model, cut side ditch model, and slope model based on the shoulder line and cross-sectional outline. The specific process is as follows: e1. Based on the shoulder line and cross-section outline, generate solid models of the embankment subgrade surface layer, embankment subgrade bottom layer, below the embankment subgrade, cut subgrade surface layer, cut subgrade bottom layer, cut side ditch and boundary range; e2. Trim the generated surface and bottom layers of the roadbed subgrade with the boundary range of the side ditch, respectively; e3. Sweep the contour line of the cut slope along the corresponding side shoulder line to generate the cut slope surface model.

[0030] Specifically, in step F, the model below the embankment subgrade and the cut slope model are trimmed to match the terrain. The specific process is as follows: f1. Trim the solid model below the embankment subgrade below the terrain surface; f2. Trim the cut slope model above the terrain surface. Example

[0031] A railway roadbed design method based on BIM technology includes the following steps: A. Read the route information model and generate the roadbed construction point alignments, as detailed below: a1. Read the spatial alignment, planar alignment, chain break data, and basic information of the project from the line model.

[0032] More specifically, the basic information of the project includes railway type, grade, design speed, number of lines, and track spacing.

[0033] a2. Based on the starting and ending mileages of the roadbed construction points and the chainage break numbers in the chainage break data, generate the starting and ending points of the roadbed construction points on the route model, as follows: First, calculate the distance to the starting point of the alignment based on the starting and ending mileages of the roadbed construction sites and the chainage break number; Then, generate the corresponding start and end point projection points on the left-line plane, and create a perpendicular plane through the projection points that is perpendicular to the left-line plane. Finally, the intersection points with the left and right spatial alignments are the starting and ending points of the roadbed construction points on the left and right lines.

[0034] a3. Using the starting and ending points obtained in step a2, the left and right spatial alignments are intercepted to obtain the left alignment of the roadbed construction point and the right alignment of the roadbed construction point.

[0035] B. Create road shoulder lines at roadbed construction points that take into account curve widening, as follows: Specifically, after horizontally and vertically offsetting the spatial alignment of the roadbed construction points, the left and right shoulder lines are obtained. When the number of lines is double-track, the left shoulder line is obtained by offsetting from the left line to the left, and the right shoulder line is obtained by offsetting from the right line to the right. The vertical offset is uniformly downward. The offset distance for different railway types is calculated as follows: Firstly, the horizontal offset of the ballastless track alignment is equal to half the width of the roadbed. Secondly, the vertical offset of the ballastless track alignment = track structure height + (half the width of the roadbed - the width of the track slab / 2) * the roadbed surface drainage slope; Third, the horizontal offset of the ballast track alignment is equal to half the width of the roadbed; Fourth, the vertical offset of the ballast track alignment = track structure height + (half width of the roadbed - track gauge / 2) * roadbed surface drainage slope.

[0036] Specifically, for ballast railways, when the subgrade construction point is located in a curved section of the line, the subgrade surface needs to be widened on the outside of the curve. According to the railway subgrade design specifications, the curve widening value can be determined by parameters such as railway type, grade, design speed, and curve radius.

[0037] More specifically, identify the transition curves and circular curves on the roadbed construction site alignment, and within the circular curve range, offset the obtained shoulder line outward along the roadbed surface drainage direction.

[0038] More specifically, the curve widening transition is achieved through a linear decrease within the transition curve range. The specific implementation method is as follows: Create points at specified mileage intervals on the shoulder line within the transition curve range, calculate the widening value of these points based on the mileage, and offset them outward along the roadbed drainage direction. Connect the offset points; merge the shoulder lines of the circular curve and the transition curve range after offset, and use them as the shoulder lines considering curve widening.

[0039] C. Based on 3D terrain data, the embankment and cutting sections within the work site are divided as follows: c1. The intersection points of the calculated left and right shoulder lines with the 3D terrain model; c2. Use the obtained intersection points to divide the shoulder line into multiple segments; c3. Generate the midpoint of the first segment of the left shoulder line and the right shoulder line respectively, and project them onto the terrain. If the z coordinate of the projected point is less than the z coordinate of the point, the segment is an embankment; otherwise, it is a cut. Add the corresponding attribute value to the shoulder line of the segment. c4. Add embankment / cutting attribute values ​​to the shoulder lines of the remaining paragraphs in sequence, with the values ​​being the opposite of those of the previous paragraph, until the last paragraph.

[0040] Since there will be no frequent transitions between embankments and cuttings during the construction process, when the length of an embankment segment is less than the set value, the attribute value of the embankment segment will be changed to that of a cutting.

[0041] D. Draw the roadbed structure, cut side ditches and boundary range, and slope cross-sectional outlines for the fill layer, as detailed below: d1. Draw the roadbed outline on the vertical plane obtained in step a2, and calculate the intersection points of the vertical plane with the left roadbed construction point line, the right roadbed construction point line, the left shoulder line, and the right shoulder line; calculate the midpoint of the roadbed surface based on the intersection points of the left and right roadbed construction point lines; using the shoulder point and the midpoint of the roadbed surface as references, draw the closed outlines of the surface layer, bottom layer, and below layer of the embankment subgrade, the surface layer, and the bottom layer of the cutting subgrade on both the left and right sides, respectively. When drawing the layer below the embankment subgrade, the thickness of this layer needs to be set to be large enough to obtain the correct result when trimming with the terrain in the following steps; d2. Using the left and right shoulder points as references, draw the left and right side ditches, the closed outline of the side ditch boundary, and the outline of the cut slope respectively; the boundary of the side ditch should be closed at the top opening of the ditch; when drawing the slope, the slope height needs to be set to be large enough so that the correct result can be obtained when trimming with the terrain later.

[0042] E. Generate embankment, cutting body, cutting side ditch, and slope models based on shoulder lines and cross-sections, as detailed below: e1. Sweep along the corresponding side shoulder lines to generate the roadbed body and side ditch solid models of the embankment surface, bottom layer, and below the embankment on both sides, as well as the cut embankment surface, bottom layer, side ditch, and boundary range closed contour lines. e2. Since the roadbed body and the side ditch have overlapping and intersecting parts, it is necessary to trim the surface layer and bottom layer models of the roadbed subgrade and the boundary range of the side ditch respectively. e3. To ensure the integrity of the cut body model, the cut slope outline needs to be swept along the corresponding side shoulder line to generate the cut slope surface model.

[0043] F. Trim the embankment subgrade model and the cut slope model to fit the terrain, including the following steps: f1. Use a 3D terrain model to trim the excess solid model below the embankment subgrade below the terrain surface; f2. Use a 3D terrain model to trim the excess road cut slope model above the terrain surface.

[0044] This invention enables forward design of railway subgrade BIM models. By reading three-dimensional line data and terrain data, it automatically completes the segment division of embankments and cuttings within subgrade construction sites. Using pre-drawn subgrade body and side ditch outlines, it creates embankment and cutting body models and realizes automatic calculation of different filler volumes.

[0045] This invention can improve the accuracy of roadbed body BIM design. By using three-dimensional measured terrain to carry out roadbed body BIM design, it effectively overcomes the drawbacks of the two-dimensional cross-section design method, making the design results closer to the actual site conditions and the filling volume calculation more accurate. For ballast railway curve sections, it can widen the roadbed surface on the outside of the curve, ensuring the consistency between the model and the design intent.

[0046] This invention enables rapid adjustment of 3D design results by drawing parametric body contours, facilitating scheme comparison and design changes, and has certain application value.

Claims

1. A railway track foundation design method based on BIM technology, characterized in that: Includes the following steps: A. Read the route information model and generate the roadbed construction point alignment; B. Create road shoulder lines at roadbed construction points that take into account curve widening; C. Based on three-dimensional terrain data, divide the embankment section and the cutting section within the work site; D. Draw the roadbed structure, cut side ditches and boundary range, and slope cross-sectional outline of the fill layer; E. Generate embankment body model, cut body model, cut side ditch model, and slope model based on shoulder line and cross-section outline; F. The model below the embankment subgrade and the model of the cut slope are trimmed according to the terrain; G. Complete the basic design of the railway track structure; Step E generates the embankment body model, cut body model, cut side ditch model, and slope model based on the shoulder line and cross-sectional outline. The specific process is as follows: e1. Based on the shoulder line and cross-section outline, generate solid models of the embankment subgrade surface layer, embankment subgrade bottom layer, below the embankment subgrade, cut subgrade surface layer, cut subgrade bottom layer, cut side ditch and boundary range; e2. Trim the generated surface and bottom layers of the roadbed subgrade with the boundary range of the side ditch, respectively; e3. Sweep the contour line of the road cut slope along the corresponding side shoulder line to generate the road cut slope surface model; Step B involves creating the shoulder lines at the roadbed construction points that take into account curve widening, as detailed below: After horizontally and vertically offsetting the spatial alignment of the roadbed construction points, the left and right shoulder lines are obtained. When the number of tracks is double-track, the left shoulder line is obtained by offsetting from the left track to the left, and the right shoulder line is obtained by offsetting from the right track to the right. The vertical offset is uniformly downward. The offset distance for different railway types is calculated as follows: Firstly, the horizontal offset of the ballastless track alignment is equal to half the width of the roadbed. Secondly, the vertical offset of the ballastless track alignment = track structure height + (half the width of the roadbed - the width of the track slab / 2) * the roadbed surface drainage slope; Third, the horizontal offset of the ballast track alignment is equal to half the width of the roadbed; Fourth, the vertical offset of the ballast track alignment = track structure height + (half width of the roadbed - track gauge / 2) * roadbed surface drainage slope; For ballasted railways, when the subgrade construction point is located in a curved section of the line, the subgrade surface needs to be widened on the outside of the curve. According to the railway subgrade design specifications, the curve widening value is determined by the railway type, grade, design speed, and curve radius parameters. Identify the transition curves and circular curves on the roadbed construction site alignment, and within the range of the circular curves, offset the obtained shoulder lines outward along the roadbed surface drainage direction. The curve widening transition is achieved by linearly decreasing within the transition curve range. The specific implementation method is as follows: Create points at specified mileage intervals on the shoulder line within the transition curve range, calculate the widening value of these points based on the mileage, and offset them outward along the roadbed drainage direction. Connect the offset points; merge the shoulder lines after offsetting the circular curve and transition curve ranges as the shoulder lines considering curve widening.

2. The railway track foundation design method based on BIM technology according to claim 1, characterized in that: The track information model in step A includes horizontal data, vertical profile data, chainage data, railway type, railway grade, design speed, number of tracks, and track spacing.

3. The railway track foundation design method based on BIM technology according to claim 2, characterized in that: Step A reads the route information model and generates the roadbed construction point alignments. The specific process is as follows: a1. Read the railway line's horizontal and vertical profile data, chainage data, railway type, railway grade, design speed, number of lines, and track spacing; a2. Based on the starting and ending mileages of the roadbed construction points and the chain break number in the chain break data, generate the starting and ending points of the roadbed construction points on the line model; a3. Using the start and end points of the roadbed construction points, the line positions of the roadbed construction points are intercepted on the line model.

4. The railway track foundation design method based on BIM technology according to claim 1, characterized in that: The shoulder widening value should decrease linearly within the transition curve range.

5. The railway track foundation design method based on BIM technology according to claim 1, characterized in that: Step C, based on 3D terrain data, divides the embankment and cutting sections within the work site, including determining and dividing the sections. The specific process is as follows: c1. Obtain the intersection points of the left shoulder line, the right shoulder line and the 3D terrain model respectively; c2. Using the intersection points obtained above, divide the shoulder line into multiple segments.

6. The railway roadbed design method based on BIM technology according to claim 5, characterized in that: Step C, based on 3D terrain data, divides the work site into embankment and cutting sections. The specific process is as follows: c3. Determine the type of roadbed in the first paragraph, specifically whether it is an embankment paragraph or a cutting paragraph; c4. Add the corresponding attribute values ​​to the shoulder lines of the above paragraphs; c5. Add embankment / cutting attribute values ​​to the shoulder lines of the remaining paragraphs in sequence, with the values ​​being the opposite of those of the previous paragraph, until the last paragraph.

7. A railway track foundation design method based on BIM technology according to claim 1, characterized in that: Step D involves drawing the roadbed structure, cut side ditches and their boundaries, and slope cross-sectional outlines for the layered fill material. The specific process is as follows: Using the left shoulder point, right shoulder point, and midpoint of the roadbed surface as references, draw the outlines of the surface layer, bottom layer, and below layer of the embankment subgrade on both the left and right sides, as well as the surface layer and bottom layer of the cut subgrade.

8. The railway track foundation design method based on BIM technology according to claim 1, characterized in that: Step D involves drawing the roadbed structure, cut side ditches and their boundaries, and slope cross-sectional outlines for the layered fill material. The specific process is as follows: Using the left and right shoulder points as references, draw the side ditches, the boundary range of the side ditches, and the outline of the slopes on both the left and right sides of the road cut.

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