A parametric modeling method and system for a through-type steel box tied arch bridge

Abstract

The present invention relates to the technical field of building information modeling, in particular to a parametric modeling method for a bottom-supported steel box tie arch bridge, comprising the following steps: using Grasshopper software to calculate the parameters required for generating arch ribs, generating a partial arch rib model, and generating the entire arch rib model by modifying the coordinate parameters; using Grasshopper software to calculate the parameters required for generating main beams, generating a partial main beam model, and generating the entire main beam model by modifying the coordinate parameters; generating a hanger positioning line according to an arch axis and a main beam control line, and then generating a hanger model; generating a hanger anchoring structure model according to the positioning line and positioning point on the hanger; and merging the arch rib model, the main beam model, the hanger model and the hanger anchoring structure model to generate a bottom-supported steel box tie arch bridge model. The method of the present invention proposes parametric modeling of special-shaped arch bridges based on Grasshopper software, thereby improving the efficiency and accuracy of modeling.

Description

Technical Field

[0001] The invention relates to the technical field of building information modeling, and in particular to a parametric modeling method and system for a bottom-supported steel box tied arch bridge. Background Art

[0002] BIM (Building Information Modeling) is another important computer application technology that has emerged in the engineering construction industry after CAD (Computer-Aided Design) technology, and is triggering an unprecedented and thorough revolution in the construction industry. This technology uses digital modeling software to improve the efficiency of project design, construction and management, and brings great added value to construction companies that adopt this technology.

[0003] Grasshopper (GH for short) is a visual programming language that runs on the Rhino software platform and is one of the mainstream software in the direction of parametric design. The characteristic of GH is that it parametrizes and programs the modeling process through visual programming, avoiding mechanical repetitive operations, so that a large number of logical modeling processes are replaced by program loop operations. Designers can obtain the corresponding model in real time by modifying the input parameters, effectively improving the efficiency of design work. The existing BIM parametric modeling software can only realize the modeling of conventional bottom-supported arch bridges, and cannot realize the parametric modeling of special-shaped arch bridges. Summary of the invention

[0004] The more complex the shape of a municipal bridge is, the more difficult it is for existing BIM modeling software to quickly and fully parameterize and build a corresponding bridge model. The present invention uses Grasshopper software to provide a parametric modeling method for a bottom-supported steel box tie arch bridge, which can generate bottom-supported steel box tie arch bridge models with different bridge deck shapes, different arch rib cross-section forms, and different cable surface arrangements according to input structural parameters. This solves the parametric modeling problem of some bottom-supported steel box tie arch bridges.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] A parametric modeling method for a through-type steel box tied arch bridge comprises the following steps:

[0007] The parameters required for generating the arch rib are calculated by Grasshopper software to generate a partial arch rib model, and the entire arch rib model is generated by modifying the coordinate parameters using the relative position relationship between the entire arch rib model and the parts. The parameters required for generating the arch rib include the arch rib rise, the arch rib calculated span, the arch foot cross-section linear shape, the arch crown cross-section linear shape, the arch axis plane projection equation, and the arch axis elevation projection equation;

[0008] The parameters required for generating the main beam are calculated by Grasshopper software to generate a partial main beam model. The entire main beam model is generated by modifying the coordinate parameters using the relative position relationship between the entire main beam model and the parts. The parameters required for generating the main beam include the main beam mid-span pre-camber, the main beam length, the main beam control line elevation projection equation, the main beam inner control line plane projection equation, the main beam outer control line plane projection equation, the main beam mid-span cross-section linear shape, and the main beam end cross-section linear shape;

[0009] Extract the inner edge or outer edge line of the top of the main beam from the main beam model, use the extracted inner edge or outer edge line of the top surface of the main beam as a reference curve for the positioning points on the arch and beam of the hanger, use the points on the reference curve divided equally according to the spacing as reference points, translate on the basis of the reference points to generate the upper and lower end positioning points of the hanger, connect the positioning points to generate the positioning line, and generate the hanger model according to the positioning line;

[0010] Generate the hanger anchor structure model based on the positioning lines and points on the hanger and the input parameters required for the lug anchoring;

[0011] The arch rib model, main beam model, hanger model and hanger anchor structure model are combined to generate a bottom-supported steel box tied arch bridge model.

[0012] As a preferred solution of the present invention, the partial arch rib model is a 1 / 4 arch rib model, and by modifying the coordinate parameters, four 1 / 4 arch rib models are sequentially generated to form the entire arch rib model.

[0013] As a preferred solution of the present invention, the partial arch rib model is a 1 / 4 arch rib model. First, the generated 1 / 4 arch rib model is symmetrical about the XZ plane to generate a 1 / 2 arch rib model; secondly, the 1 / 2 arch rib model is symmetrical about the YZ vertical plane to form the entire arch rib model.

[0014] As a preferred embodiment of the present invention, the step of generating the 1 / 4 arch rib model comprises:

[0015] According to the arch rib rise and span calculation, the arch axis plane projection equation and elevation projection equation are generated;

[0016] According to the plane projection equation of the arch axis, N coordinate points on the curve are calculated, and the N coordinate points are generated and connected in sequence to generate the plane projection curve of the arch axis;

[0017] According to the vertical equation of the arch axis, M coordinate points on the curve are calculated, and the M coordinate points are generated and connected in sequence to generate the vertical projection curve of the arch axis;

[0018] The arch axis plane projection curve is stretched in the Z direction to form a first curved surface, and the arch axis elevation projection curve is stretched in the X direction to form a second curved surface. The intersection of the first curved surface and the second curved surface is the arch axis.

[0019] Place the cross-section line of the vault at the top of the arch axis, and place the cross-section line of the arch foot at the end of the arch axis. The plane where the cross-section line of the vault and the cross-section line of the arch foot are located is perpendicular to the arch axis.

[0020] Generate an initialized 1 / 4 arch rib model according to the cross-sectional linear shape of the arch crown, the cross-sectional linear shape of the arch foot and the arch axis;

[0021] Extracting the edge line of the initialized 1 / 4 arch rib model, and extending the edge line along the arch axis toward the arch foot to generate an extended arch rib wall panel surface, wherein the extended arch rib wall panel surface is combined with the initialized 1 / 4 arch rib model to form an extended 1 / 4 arch rib model;

[0022] The elevation projection curve of the main beam control line is stretched in the Y direction to form a surface, and the excess part of the extended 1 / 4 arch rib model is cut off by the surface formed by stretching, and the remaining part is the 1 / 4 arch rib model.

[0023] As a preferred solution of the present invention, the partial main beam model is a 1 / 4 main beam model, and four 1 / 4 main beam models are generated in sequence by modifying the coordinate parameters to form the entire main beam model;

[0024] or;

[0025] The generated 1 / 4 main beam model is symmetrical about the XZ plane to generate a 1 / 2 main beam model; the 1 / 2 main beam model is symmetrical about the YZ vertical plane to form the entire main beam model.

[0026] As a preferred solution of the present invention, the step of generating the 1 / 4 main beam model includes:

[0027] Generate the elevation projection equation of the main beam control line, the plane equation of the main beam inner control line and the plane equation of the main beam outer control line according to the mid-span pre-camber of the main beam and the main beam length;

[0028] According to the elevation projection equation of the main beam control line, J coordinate points on the curve are calculated, and the J coordinate points are generated and connected to generate the elevation projection curve of the main beam control line;

[0029] According to the plane equation of the control line inside the main beam, K coordinate points on the curve are calculated, and the K coordinate points are generated and connected to generate the plane projection curve of the control line inside the main beam;

[0030] According to the plane equation of the main beam outer control line, L coordinate points on the curve are calculated, and the L coordinate points are generated and connected to generate the plane projection curve of the main beam outer control line;

[0031] The plane projection curve of the inner control line of the main beam and the plane projection curve of the outer control line of the main beam are stretched in the Z direction into a third curved surface, and the third curved surface is two, and the elevation projection curve of the main beam control line is stretched in the Y direction into a fourth curved surface, and the intersection line of the third curved surface and the fourth curved surface is the inner control line of the main beam and the outer control line of the main beam;

[0032] Input the cross-section line shape of the main beam in the middle span, and move it to the end point of the middle span side of the control line in the main beam; input the cross-section line shape of the end of the main beam, and move it to the end point of the bridge head side of the control line in the main beam; the plane where the cross-section line shape of the main beam in the middle span and the cross-section line shape of the end of the main beam are located forms a specified angle with the control line;

[0033] According to the cross-sectional linear shape of the main beam top span, the cross-sectional linear shape of the main beam end, the inner control line of the main beam and the outer control line of the main beam, the Sweep2 command is used to generate a 1 / 4 main beam model.

[0034] As a preferred solution of the present invention, it also includes generating an arch-beam combined segment model and a merged segment model,

[0035] The method for generating the arch-beam combination segment model comprises:

[0036] Input the beam body edge line of the arch-beam combination section, combine it with the control line inside the main beam, use the Boundary Surfaces command to generate the top surface of the combination section, use Exturde to stretch the top plate in the negative direction of the Z axis by the thickness of the beam height to form a 1 / 4 arch-beam combination section model; make the generated 1 / 4 arch-beam combination section model symmetrical about the XZ plane to generate a 1 / 2 arch-beam combination section model; make the 1 / 2 arch-beam combination section model symmetrical about the YZ vertical plane to form the entire arch-beam combination section model.

[0037] The method for generating the merged segment model comprises:

[0038] The inner control line of the main beam is symmetrical along the XZ plane, and the two symmetrical inner control lines are input into the Ruled Surface command to generate a surface. The surface is stretched along the negative direction of the Z axis by the height of the main beam to generate a block containing the merged segment.

[0039] According to the plane equation of the control line of the main beam merging section, P coordinate points on the curve are calculated, and the P coordinate points are connected to generate the plane projection curve of the control line of the main beam merging section;

[0040] Stretch the plane projection curve of the main beam merged section control line along the positive direction of the Z axis;

[0041] Using the stretched surface to split the block containing the merged segment, deleting the redundant part, and generating a 1 / 2 merged segment model;

[0042] Make the completed 1 / 2 merged segment model symmetrical about the YZ plane to form the entire merged segment model.

[0043] As a preferred embodiment of the present invention, the steps for generating the hanger model shown mainly include determining the hanger positioning points on the arch, determining the hanger positioning points on the beam, and sequentially connecting the hanger positioning points on the arch and the hanger positioning points on the beam of the corresponding hangers to form a hanger axis, using the PIPE tool to input the hanger radius, and generating a hanger solid model.

[0044] As a preferred solution of the present invention, the positioning point of the arch suspension rod is determined including:

[0045] Read the arch axis on the arch rib model and make a judgment to ensure that the starting point of the arch axis is located at the mid-span side of the bridge;

[0046] According to the inputted spacing of the hangers on the arch and the distance between the first hanger and the end point of the arch axis, the distance between the positioning point on the arch of each hanger and the end point of the arch axis is calculated;

[0047] According to the calculated distance between the arch positioning point of the hanger rod and the end point of the arch axis, the end points of the arch axis are copied on the arch axis in sequence to generate the arch positioning reference point of the arch hanger rod;

[0048] Input the translation distance of the arch hanger locating point, and move the arch hanger locating reference point along the bridge transverse direction to generate the final arch hanger locating point;

[0049] The determination of the locating point of the suspension rod on the beam includes:

[0050] Read the main beam inner control line of the main beam model and make a judgment to ensure that the starting point of the main beam inner control line is located at the mid-span side of the bridge and the end point is located at the bridge head side;

[0051] According to the inputted spacing of the hanger rods on the beam and the distance between the first hanger rod and the end point of the beam positioning line, the distance between the positioning point of each hanger rod on the beam and the end point of the beam positioning line is calculated;

[0052] According to the calculated distance between the beam hanger rod positioning point and the beam positioning line end point, the beam positioning line end points are copied on the beam positioning line in sequence to generate the beam hanger rod positioning reference point;

[0053] Enter the translation distance of the beam hanger rod positioning point, and use the Move tool to move the beam hanger rod positioning reference point along the bridge horizontal direction to generate the final beam hanger rod positioning point;

[0054] Connect the hanger positioning points on the arch and the hanger positioning points on the beam in sequence to form the hanger axis; then use the Pipe tool to input the hanger radius and generate the hanger model according to the hanger axis.

[0055] Based on the same concept, a parametric modeling system for a bottom-supported steel box tie-arch bridge is also proposed, comprising at least one processor and a memory communicatively connected to the at least one processor; the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute any of the methods described above.

[0056] Compared with the prior art, the present invention has the following beneficial effects:

[0057] Compared with the traditional design method, the method of the present invention can freely specify any cross-sectional form and arch axis line shape of the arch rib; any cross-sectional form and plane line shape of the main beam; any spacing arrangement and arrangement method of the hanger rod, and proposes parametric modeling of special-shaped arch bridges based on Grasshopper software, which improves the modeling efficiency and modeling accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 This is a flow chart of a parametric modeling method for a through-type steel box tied arch bridge in Example 1 of the present invention;

[0059] Figure 2 It is a schematic diagram of generating an initialized 1 / 4 arch rib model in Embodiment 1 of the present invention;

[0060] Figure 3 This is a schematic diagram of the state of the arch axis of the initialized 1 / 4 arch rib model in Example 1 of the present invention;

[0061] Figure 4 This is a schematic diagram of the state of extending the rear arch axis in Example 1 of the present invention;

[0062] Figure 5 It is a schematic diagram of using a stretching surface to shear off the redundant part of the extended arch rib model in Example 1 of the present invention;

[0063] Figure 6 This is a schematic diagram of the entire arch rib model in Example 1 of the present invention;

[0064] Figure 7 is a plane projection curve of the main beam merging section control line in Embodiment 1 of the present invention;

[0065] Figure 8 It is a surface stretched along the positive direction of the Z axis by the plane projection curve of the merged segment control line in Example 1 of the present invention;

[0066] Fig. 9 This is a schematic diagram of the main beam merged section model in Example 1 of the present invention;

[0067] Fig.10 This is a diagram of a 1 / 4 suspension rod model in Example 1 of the present invention;

[0068] Fig.11 This is a diagram of a 1 / 2 suspension rod model in Example 1 of the present invention;

[0069] Fig.12 This is a model diagram of a bottom-supported steel box tied arch bridge generated by merging in Example 1 of the present invention. DETAILED DESCRIPTION

[0070] The present invention is further described in detail below in conjunction with test examples and specific implementation methods. However, this should not be understood as the scope of the above subject matter of the present invention being limited to the following embodiments, and all technologies realized based on the content of the present invention belong to the scope of the present invention.

[0071] Example 1

[0072] A parametric modeling method for a through-type steel box tied arch bridge, the flow chart is as follows Figure 1 As shown, the following steps are included:

[0073] The parameters required for generating the arch rib are calculated by Grasshopper software to generate a partial arch rib model, and the entire arch rib model is generated by modifying the coordinate parameters using the relative position relationship between the entire arch rib model and the parts. The parameters required for generating the arch rib include the arch rib rise, the arch rib calculated span, the arch foot cross-section linear shape, the arch crown cross-section linear shape, the arch axis plane projection equation, and the arch axis elevation projection equation;

[0074] The parameters required for generating the main beam are calculated by Grasshopper software to generate a partial main beam model. The entire main beam model is generated by modifying the coordinate parameters using the relative position relationship between the entire main beam model and the parts. The parameters required for generating the main beam include the plane projection equation of the main beam, the elevation projection equation of the main beam control line, the cross-section line shape of the main beam mid-span, and the cross-section line shape of the main beam end.

[0075] Extract the inner edge or outer edge line of the main beam from the main beam model, use the extracted inner edge or outer edge line of the main beam as a reference curve for positioning points on the hanger arch and the beam, use points on the reference curve divided equally according to the spacing as reference points, perform translation on the basis of the reference points to generate the upper and lower end positioning points of the hanger, connect the positioning points to generate the positioning line, and generate the hanger model according to the positioning line;

[0076] Generate the hanger anchor structure model based on the positioning lines and points on the hanger and the input parameters required for the lug anchoring;

[0077] The arch rib model, main beam model, hanger model and hanger anchor structure model are combined to generate a bottom-supported steel box tied arch bridge model.

[0078] This embodiment is described by first generating a 1 / 4 arch rib model, modifying the coordinate parameters, and sequentially generating 4 1 / 4 arch rib models to form the entire arch rib model as an example, and also by first generating a 1 / 4 main beam model, modifying the coordinate parameters, and sequentially generating 4 1 / 4 main beam models to form the entire main beam model as an example.

[0079] This method mainly includes the following four steps:

[0080] Arch rib generation: Input the parameters required for arch rib generation, including arch rib rise, arch rib calculated span, arch foot section, and arch crown section. According to the arch rib rise and arch rib calculated span, the plane projection equation and the elevation projection equation of the arch axis are formulated. Then, according to the input parameters, Grasshopper calculates and generates a 1 / 4 arch rib model. Secondly, by modifying the coordinate parameters and repeating the above operation 4 times, 4 arch rib models can be generated in sequence to form the entire arch rib model. (If the bridge model is symmetrical about the center of the bridge midpoint, the generated 1 / 4 arch rib model can be symmetrical about the XZ plane first, and then together with the original and symmetrically generated arch rib model, it can be symmetrical about the YZ vertical plane to form the entire arch rib model).

[0081] Main beam generation: Input the parameters required for main beam generation, including arch rib rise and calculated span, main beam longitudinal slope, mid-span arc radius, and beam height. Generate the elevation projection equation of the main beam control line, the plane equation of the main beam inner control line, and the main beam outer control line according to the arch rib rise and calculated span, and then calculate and generate a 1 / 4 main beam model through Grasshopper based on the input parameters (the generation method of the rest of the main beam is the same as the arch rib).

[0082] To generate the suspender, input the parameters required for the main beam generation, including the anchor spacing on the suspender beam, the anchor spacing on the arch, and the diameter of the suspender cross section. Extract the arch axis generated above, and the internal or external axis of the main beam as the reference curve for the locating points on the suspender arch and beam. Use the points on the reference curve that are equally divided according to the spacing as the upper and lower locating points of the suspender, and connect the locating points to generate the suspender model.

[0083] Secondly, the hanger anchoring structural model is generated according to the hanger positioning line and positioning points, plus the input parameters required for the ear plate anchoring.

[0084] The above generated models are combined to form a bottom-supported steel box tied arch bridge model.

[0085] The generation logic of the arch rib model, main beam model, hanger model and hanger anchor structure model will be described in detail below.

[0086] Arch rib model generation

[0087] Prepare the input parameters: arch rib rise, calculated span, arch axis plane projection equation, arch axis elevation projection equation, arch foot section linear shape, arch crown section linear shape, arch foot section linear shape and arch crown section linear shape are Figure 2 The two triangles in the figure. The arch axis plane projection equation and the arch axis elevation projection equation are two function equations established separately. Through the above two equations, the overall shape of the arch rib model can be determined. The arch rib rise and the calculated span are important parameters in the two equations, which determine the length of the arch rib model along the bridge direction and the transverse bridge direction.

[0088] As a specific embodiment, the arch axis plane projection equation in this embodiment is the projection equation of the arch axis curve on the XY plane of the XYZ three-dimensional coordinate system, and the calculation formula is:

[0089] ;

[0090] The projection equation of the arch rib facade is the projection equation on the XY plane of the XYZ three-dimensional coordinate system, and the calculation formula is:

[0091] ;

[0092] Among them, X, Y, and Z represent the three-dimensional coordinates of the points on the arch axis curve.

[0093] The above arch axis plane projection equation and arch axis elevation projection equation are only examples, and are not limited to this equation. In engineering applications, various types of arch axis plane projection equations and arch axis elevation projection equations can be customized as needed, and the arch axis plane projection equation and arch axis elevation projection equation can be used as variables to finally generate an arch rib model together with other input parameters.

[0094] According to the arch rib rise, the span is calculated to generate the plane projection equation and the elevation projection equation of the arch axis.

[0095] According to the plane equation of the arch axis, N coordinate points on the curve are calculated, and the coordinate points are connected to generate the plane projection curve of the arch axis.

[0096] According to the vertical equation of the arch axis, M coordinate points on the curve are calculated, and the coordinate points are connected to generate the vertical projection curve of the arch axis.

[0097] The plane projection curve of the arch axis is stretched into a curved surface in the Z direction, and the elevation projection curve of the arch axis is stretched into a curved surface in the X direction. The intersection of the two curved surfaces is the arch axis. Among them, an XYZ three-dimensional coordinate system is established, where the X direction is defined as the longitudinal direction of the bridge, the Y direction is defined as the transverse direction of the bridge, and the Z direction is the vertical direction in space.

[0098] Enter the cross-sectional linear shape of the vault, and move it to the top of the arch on the arch axis. Enter the cross-sectional linear shape of the arch foot, and move it to the end of the arch on the arch axis. Make sure that the plane where the linear shape is located is perpendicular to the arch axis.

[0099] According to the cross-sectional linear shape of the arch crown, the cross-sectional linear shape of the arch foot, and the arch axis, a single arch rib model is generated using the sweep1 command. The schematic diagram of the generated initial 1 / 4 arch rib model is as follows: Figure 2 shown.

[0100] Extract the edge line of a single arch rib model, and use the EXTEND CURVE command to extend it along the arch axis toward the arch foot. Use the sweep1 command to generate the extended arch rib wall panel surface. The schematic diagram of extending along the arch axis toward the arch foot is shown in the figure below. Figure 3 and Figure 4 As shown, Figure 3 To initialize the state of the arch axis of the 1 / 4 arch rib model, Figure 4 This is the state of the arch axis after extension. The extended arch axis and the previously generated arch rib model form a whole, that is, the extended arch rib model.

[0101] Extract the top control line of the bridge deck of the main beam, stretch the control line in the Y direction to form a surface, and use this surface to cut off the excess part of the extended arch rib model. The remaining part is the completed single arch rib model. The schematic diagram of using the stretched surface to cut off the excess part of the extended arch rib model is as follows Figure 5 shown.

[0102] The completed single arch rib model is made symmetrical about the XZ plane and the YZ plane to form the entire arch rib model. The schematic diagram of the entire arch rib model is as follows Figure 6 shown.

[0103] Main beam model generation

[0104] Prepare input parameters: main beam length, main beam mid-span pre-camber, main beam mid-span cross-sectional linear shape, main beam end cross-sectional linear shape, main beam inner control line plane projection equation, main beam outer control line plane projection equation, main beam control line elevation projection equation.

[0105] According to the main beam length and the pre-arch of the main beam in the middle of the span, the elevation projection equation of the main beam control line, the plane equation of the inner control line of the main beam and the plane equation of the outer control line of the main beam can be generated.

[0106] Based on the main beam model in this embodiment, the plane projection equation of the control line in the main beam is expressed as:

[0107] ;

[0108] Among them, X, Y, and Z represent the three-dimensional coordinates of the points on the inner edge curve of the beam. The above plane projection equation of the control line inside the main beam is only an example, and it is not limited to this equation for the inner edge line of the beam. In engineering applications, various types of equations can be customized according to needs, and the plane projection equation of the control line inside the main beam is used as a variable to finally generate the main beam model together with other input parameters.

[0109] According to the elevation projection equation of the main beam control line, J coordinate points on the curve are calculated, and the coordinate points are connected to generate the elevation projection curve of the main beam control line.

[0110] According to the plane equation of the control line inside the main beam, K coordinate points on the curve are calculated, and the coordinate points are connected to generate the plane projection curve of the control line inside the main beam.

[0111] According to the plane equation of the main beam outer control line, L coordinate points on the curve are calculated, and the coordinate points are connected to generate the plane projection curve of the main beam outer control line.

[0112] The plane projection curve of the inner and outer control lines of the main beam is stretched into a curved surface in the Z direction, and the vertical projection curve of the beam is stretched into a curved surface in the X direction. The intersection of the two curved surfaces is the inner and outer control lines of the main beam.

[0113] Enter the cross-section linear shape of the main beam at mid-span, and move it to the end point of the control line in the main beam at mid-span. Enter the cross-section linear shape of the main beam end, and move it to the end point of the control line in the main beam at the bridgehead side, and ensure that the plane where the linear shape is located forms a specified angle with the control line.

[0114] According to the cross-sectional linear shape of the main beam top span, the cross-sectional linear shape of the main beam ends, and the inner and outer control lines of the main beam, the sweep2 command is used to generate a single 1 / 4 main beam model.

[0115] Input the edge line of the arch-beam joint section, combined with the control line inside the main beam, use the Boundary Surfaces command to generate the top surface of the joint section, and use Exturde to stretch the top plate in the negative direction along the Z axis by the thickness of the beam height to form the arch-beam joint section model.

[0116] Make the completed 1 / 4 main beam model symmetrical about the XZ plane and the YZ plane to form the entire main beam model.

[0117] Main beam merged segment model generation

[0118] Enter the plane equation of the merged segment control line:

[0119] ;

[0120] Among them, X, Y, and Z represent the three-dimensional coordinates of the points on the inner edge curve of the beam. The above equation is only an example, and it is not limited to this equation for the plane equation of the merged segment control line. In engineering applications, various types of equations can be customized according to needs, and the plane equation of the merged segment control line can be used as a variable to finally generate a model together with other input parameters.

[0121] The inner control line of the main beam is symmetrical along the XZ plane, and the two symmetrical inner control lines are input into the Ruled Surface command to generate a surface. The surface is stretched along the negative direction of the Z axis by the height of the main beam to generate a block containing the merged segment.

[0122] According to the plane equation of the main beam merging section control line, calculate P coordinate points on the curve, connect the coordinate points, and generate the plane projection curve of the main beam merging section control line. Figure 7 shown.

[0123] The plane projection curve of the merged segment control line is stretched along the positive direction of the Z axis to form a surface. The plane projection curve of the generated merged segment control line is stretched along the positive direction of the Z axis to form a surface. Figure 8 shown.

[0124] Use the stretched surface to split the block containing the merged segment, delete the redundant part, and generate a 1 / 2 merged segment model.

[0125] Make the completed 1 / 2 merged segment model symmetrical about the YZ plane to form the entire merged segment model. The generated main beam merged segment model is as follows: Fig. 9 shown.

[0126] Boom model generation

[0127] The steps of generating the hanger model include: extracting the inner edge or outer edge line of the main beam from the main beam model, using the extracted inner edge or outer edge line of the main beam as a reference curve for positioning points on the hanger arch and the beam, using points on the reference curve divided equally at intervals as reference points, translating on the basis of the reference points to generate the upper and lower end positioning points of the hanger, connecting the positioning points to generate a positioning line, and generating the hanger model according to the positioning line.

[0128] As a specific embodiment, the step of generating the boom model includes the following steps:

[0129] Prepare to input parameters: arch axis, inner positioning line of main beam, spacing between hangers on arch, spacing between hangers on beam, lateral translation distance of hangers on arch, lateral translation distance of hangers on beam.

[0130] Determination of the positioning point of the arch hanger:

[0131] Read the arch axis generated in the previous article and make a judgment to ensure that the starting point of the curve is located on the mid-span side of the bridge and the end point is located on the bridge head side. If the direction of the straight line is reversed, the FILP CURVE tool can be used to reverse the straight line.

[0132] Using the series tool, based on the input spacing of the hangers on the arch and the distance between the first hanger and the end point of the arch axis, the distance between each hanger positioning point and the end point of the arch axis is calculated.

[0133] According to the calculated distance between the hanger positioning point and the end point of the arch axis, the end points of the arch axis are copied on the arch axis in sequence to generate the hanger positioning point on the arch.

[0134] Input the translation distance of the arch hanger locating point, and use the MOVE tool to move the point laterally along the bridge to generate the final arch hanger locating point.

[0135] Determination of the positioning point of the hanger rod on the beam:

[0136] Read the control line inside the main beam generated in the previous article and make a judgment to ensure that the starting point of the curve is located on the mid-span side of the bridge and the end point is located on the bridge head side. If the direction of the straight line is reversed, the FILP CURVE tool can be used to reverse the straight line.

[0137] Use the series tool to calculate the distance between each hanger positioning point and the end point of the beam positioning line based on the input hanger spacing on the beam and the distance between the first hanger and the end point of the beam positioning line.

[0138] According to the calculated distance between the hanger locating point and the end point of the beam locating line, the end points of the beam locating line are copied sequentially on the beam locating line to generate the hanger locating point on the beam.

[0139] Input the translation distance of the hanger rod locating point on the beam, and use the MOVE tool to generate the final hanger rod locating point on the beam by moving the point horizontally along the bridge.

[0140] Connect the corresponding suspender's arch positioning points and beam positioning points in sequence to form the suspender axis. Use the PIPE tool to input the suspender radius and generate the suspender solid model.

[0141] Make the completed 1 / 4 suspender model symmetrical about the XZ plane and the YZ plane to form the suspender model of the entire bridge. Fig.10 As shown, the 1 / 2 suspension rod model is shown in Fig.11 shown.

[0142] Finally, all components are merged to form a bridge model. The generated bottom-supported steel box tied arch bridge model is shown in the figure below. Fig.12 shown.

[0143] The beneficial effects of the present invention are:

[0144] 1. The present invention adopts Grasshopper software to provide a parametric modeling method for a through-type steel box tied arch bridge, which can generate a through-type steel box tied arch bridge model according to input structural parameters, thereby solving the parametric modeling problem of special-shaped through-type steel box tied arch bridges.

[0145] 2. The bottom-supported steel box tie arch bridge generated by the present invention has wide adaptability and can be of different bridge deck shapes, different arch rib cross-section forms, and different cable arrangements.

[0146] 3. The generation of the model of the present invention is completely driven by parameters such as the arch rib linear shape, the main beam linear shape, the arch rib cross-sectional size, the main beam cross-sectional size, the cable arrangement position, etc., and the model can be quickly generated and modified by modifying the parameters.

[0147] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A parametric modeling method for a through-type steel box tied arch bridge, characterized in that: The following steps are involved: The parameters required for generating the arch rib are calculated by Grasshopper software to generate a partial arch rib model, and the entire arch rib model is generated by modifying the coordinate parameters using the relative position relationship between the entire arch rib model and the parts. The parameters required for generating the arch rib include the arch rib rise, the arch rib calculated span, the arch foot cross-section linear shape, the arch crown cross-section linear shape, the arch axis plane projection equation, and the arch axis elevation projection equation; The parameters required for generating the main beam are calculated by Grasshopper software to generate a partial main beam model. The entire main beam model is generated by modifying the coordinate parameters using the relative position relationship between the entire main beam model and the parts. The parameters required for generating the main beam include the main beam mid-span pre-camber, the main beam length, the main beam control line elevation projection equation, the main beam inner control line plane projection equation, the main beam outer control line plane projection equation, the main beam mid-span cross-section linear shape, and the main beam end cross-section linear shape; Extract the inner edge or outer edge line of the top of the main beam from the main beam model, use the extracted inner edge or outer edge line of the top surface of the main beam as a reference curve for the positioning points on the arch and beam of the hanger, use the points on the reference curve divided equally according to the spacing as reference points, translate on the basis of the reference points to generate the upper and lower end positioning points of the hanger, connect the positioning points to generate the positioning line, and generate the hanger model according to the positioning line; Generate the hanger anchor structure model based on the positioning lines and points on the hanger and the input parameters required for the lug anchoring; The arch rib model, main beam model, hanger model and hanger anchor structure model are combined to generate a bottom-supported steel box tied arch bridge model.

2. A parametric modeling method for a through steel box tied arch bridge according to claim 1, characterized in that: The partial arch rib model is a 1 / 4 arch rib model. By modifying the coordinate parameters, four 1 / 4 arch rib models are generated in sequence to form the entire arch rib model.

3. The parametric modeling method for a through steel box tied arch bridge according to claim 1, characterized in that: The partial arch rib model is a 1 / 4 arch rib model. First, the generated 1 / 4 arch rib model is symmetrical about the XZ plane to generate a 1 / 2 arch rib model; secondly, the 1 / 2 arch rib model is symmetrical about the YZ vertical plane to form the entire arch rib model.

4. A parametric modeling method for a through steel box tied arch bridge according to claim 2 or 3, characterized in that: The steps of generating the 1 / 4 arch rib model include: According to the arch rib rise and span calculation, the arch axis plane projection equation and elevation projection equation are generated; According to the plane projection equation of the arch axis, N coordinate points on the curve are calculated, and the N coordinate points are generated and connected in sequence to generate the plane projection curve of the arch axis; According to the vertical equation of the arch axis, M coordinate points on the curve are calculated, and the M coordinate points are generated and connected in sequence to generate the vertical projection curve of the arch axis; The arch axis plane projection curve is stretched in the Z direction to form a first curved surface, and the arch axis elevation projection curve is stretched in the X direction to form a second curved surface. The intersection of the first curved surface and the second curved surface is the arch axis. Place the cross-section line of the vault at the top of the arch axis, and place the cross-section line of the arch foot at the end of the arch axis. The plane where the cross-section line of the vault and the cross-section line of the arch foot are located is perpendicular to the arch axis. Generate an initialized 1 / 4 arch rib model according to the cross-sectional linear shape of the arch crown, the cross-sectional linear shape of the arch foot and the arch axis; Extracting the edge line of the initialized 1 / 4 arch rib model, and extending the edge line along the arch axis toward the arch foot to generate an extended arch rib wall panel surface, wherein the extended arch rib wall panel surface is combined with the initialized 1 / 4 arch rib model to form an extended 1 / 4 arch rib model; The elevation projection curve of the main beam control line is stretched in the Y direction to form a surface, and the excess part of the extended 1 / 4 arch rib model is cut off by the surface formed by stretching, and the remaining part is the 1 / 4 arch rib model.

5. The parametric modeling method for a through steel box tied arch bridge according to claim 1, characterized in that: The partial main beam model is a 1 / 4 main beam model, and by modifying the coordinate parameters, four 1 / 4 main beam models are generated in sequence to form the entire main beam model; or; The generated 1 / 4 main beam model is symmetrical about the XZ plane to generate a 1 / 2 main beam model; the 1 / 2 main beam model is symmetrical about the YZ vertical plane to form the entire main beam model.

6. A parametric modeling method for a through steel box tied arch bridge as claimed in claim 5, characterized in that: The steps of generating the 1 / 4 main beam model include: Generate the elevation projection equation of the main beam control line, the plane equation of the main beam inner control line and the plane equation of the main beam outer control line according to the mid-span pre-camber of the main beam and the main beam length; According to the elevation projection equation of the main beam control line, J coordinate points on the curve are calculated, and the J coordinate points are generated and connected to generate the elevation projection curve of the main beam control line; According to the plane equation of the control line inside the main beam, K coordinate points on the curve are calculated, and the K coordinate points are generated and connected to generate the plane projection curve of the control line inside the main beam; According to the plane equation of the main beam outer control line, L coordinate points on the curve are calculated, and the L coordinate points are generated and connected to generate the plane projection curve of the main beam outer control line; The plane projection curve of the inner control line of the main beam and the plane projection curve of the outer control line of the main beam are stretched in the Z direction into a third curved surface, and the third curved surface is two, and the elevation projection curve of the main beam control line is stretched in the Y direction into a fourth curved surface, and the intersection line of the third curved surface and the fourth curved surface is the inner control line of the main beam and the outer control line of the main beam; Input the cross-section line shape of the main beam in the middle span, and move it to the end point of the middle span side of the control line in the main beam; input the cross-section line shape of the end of the main beam, and move it to the end point of the bridge head side of the control line in the main beam; the plane where the cross-section line shape of the main beam in the middle span and the cross-section line shape of the end of the main beam are located forms a specified angle with the control line; According to the cross-sectional linear shape of the main beam top span, the cross-sectional linear shape of the main beam end, the inner control line of the main beam and the outer control line of the main beam, the Sweep2 command is used to generate a 1 / 4 main beam model.

7. A parametric modeling method for a through steel box tied arch bridge as claimed in claim 5, characterized in that: It also includes the generation of arch-beam combined segment model and merged segment model. The method for generating the arch-beam combination segment model comprises: Input the beam body edge line of the arch-beam combination section, combine it with the control line inside the main beam, use the Boundary Surfaces command to generate the top surface of the combination section, use Exturde to stretch the top plate in the negative direction of the Z axis by the thickness of the beam height to form a 1 / 4 arch-beam combination section model; make the generated 1 / 4 arch-beam combination section model symmetrical about the XZ plane to generate a 1 / 2 arch-beam combination section model; make the 1 / 2 arch-beam combination section model symmetrical about the YZ vertical plane to form the entire arch-beam combination section model; The method for generating the merged segment model comprises: The inner control line of the main beam is symmetrical along the XZ plane, and the two symmetrical inner control lines are input into the Ruled Surface command to generate a surface. The surface is stretched along the negative direction of the Z axis by the height of the main beam to generate a block containing the merged segment. According to the plane equation of the control line of the main beam merging section, P coordinate points on the curve are calculated, and the P coordinate points are connected to generate the plane projection curve of the control line of the main beam merging section; Stretch the plane projection curve of the main beam merged section control line along the positive direction of the Z axis; Using the stretched surface to split the block containing the merged segment, deleting the redundant part, and generating a 1 / 2 merged segment model; Make the completed 1 / 2 merged segment model symmetrical about the YZ plane to form the entire merged segment model.

8. A parametric modeling method for a through steel box tied arch bridge according to any one of claims 1, 2, 3, 5-7, characterized in that: The steps for generating the hanger model shown mainly include determining the hanger positioning points on the arch, determining the hanger positioning points on the beam, and sequentially connecting the hanger positioning points on the arch and the hanger positioning points on the beam of the corresponding hanger to form the hanger axis, using the PIPE tool, inputting the hanger radius, and generating the hanger solid model.

9. A parametric modeling method for a through steel box tied arch bridge as claimed in claim 8, characterized in that: The determination of the positioning point of the suspension rod on the arch includes: Read the arch axis on the arch rib model and make a judgment to ensure that the starting point of the arch axis is located at the mid-span side of the bridge; According to the inputted spacing of the hangers on the arch and the distance between the first hanger and the end point of the arch axis, the distance between the positioning point on the arch of each hanger and the end point of the arch axis is calculated; According to the calculated distance between the arch positioning point of the hanger rod and the end point of the arch axis, the end points of the arch axis are copied on the arch axis in sequence to generate the arch positioning reference point of the arch hanger rod; Input the translation distance of the arch hanger locating point, and move the arch hanger locating reference point along the bridge transverse direction to generate the final arch hanger locating point; The determination of the locating point of the suspension rod on the beam includes: Read the main beam inner control line of the main beam model and make a judgment to ensure that the starting point of the main beam inner control line is located at the mid-span side of the bridge and the end point is located at the bridge head side; According to the inputted spacing of the hanger bars on the beam and the distance between the first hanger bar and the end point of the beam positioning line, the distance between the positioning point of each hanger bar on the beam and the end point of the beam positioning line is calculated; According to the calculated distance between the beam hanger rod positioning point and the beam positioning line end point, the beam positioning line end points are copied on the beam positioning line in sequence to generate the beam hanger rod positioning reference point; Enter the translation distance of the beam hanger rod positioning point, and use the Move tool to move the beam hanger rod positioning reference point along the bridge horizontal direction to generate the final beam hanger rod positioning point; Connect the hanger positioning points on the arch and the hanger positioning points on the beam in sequence to form the hanger axis; then use the Pipe tool to input the hanger radius and generate the hanger model according to the hanger axis.

10. A parametric modeling system for a through-type steel box tied arch bridge, characterized in that: It includes at least one processor and a memory communicatively connected to the at least one processor; the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to execute the method described in any one of claims 1 to 9.

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