A tunnel portal three-dimensional digital design method for smart highway

Abstract

The application provides a tunnel portal three-dimensional digital design method for smart highways, comprising the following steps: determining the selected portal position based on the design data of the tunnel, and constructing the three-dimensional ground model of the portal; judging the portal form according to the portal position and the three-dimensional ground model; the portal form comprises an end wall type, a bias type and a bamboo cutting type; automatically designing the corresponding parameters according to external instructions and the portal form to form an initial design scheme; wherein each portal form in the initial design scheme comprises the following general parameters: position, side slope, open tunnel lining, open tunnel backfill and water interception ditch; adjusting the specified parameters in the initial design scheme according to external instructions; constructing the BIM three-dimensional model of the portal according to the adjusted design scheme, and calculating the engineering quantity. The application efficiently performs full-professional and full-element digital design of the portal, and completes automatic calculation of the engineering quantity, thereby improving the accuracy and efficiency of drawing.

Description

Technical Field

[0001] This invention belongs to the field of drill-and-blast highway tunnel technology, specifically relating to a three-dimensional digital design method for tunnel portals for smart highways. Background Technology

[0002] In building a high-precision positioning and refined spatiotemporal service platform, the construction of digital highways is one of the fundamental tasks. As a crucial component of highways, tunnel engineering's digitalization is a key link and core function. The main content of tunnel digital engineering construction focuses on the digital design stage, with the tunnel portals being the part most closely related to operation and maintenance. Therefore, high-quality digital engineering of tunnel portals has become a key focus of digital highway construction.

[0003] The tunnel portal is a critical structure connecting the tunnel to the external environment. Its design and construction directly affect the overall safety and function of the tunnel. Traditional drill-and-blast tunnel portal construction typically follows these steps:

[0004] In tunnel engineering, the portal is a critical structure connecting the tunnel to the external environment, and its design and construction quality directly affect the overall safety and functionality of the tunnel. Taking drill-and-blast construction as an example, the traditional tunnel portal construction process typically includes:

[0005] Excavation of the tunnel entrance: Based on the geological conditions and design requirements, select an appropriate excavation plan and carry out the tunnel entrance excavation operation;

[0006] Slope protection: During the excavation of slopes, timely support should be provided to ensure construction safety;

[0007] Lining of open passages: After the initial support is completed, lining construction is carried out in the area from the opening to the boundary between open and closed passages;

[0008] Portal Structure: Construct the portal end walls, external retaining walls, and other structures to complete the main portal structure;

[0009] Backfilling of the tunnel: Backfilling the excavated space between the side slope and the tunnel lining;

[0010] Permanent protection: Implement permanent protective measures for the area above the backfill surface.

[0011] However, existing methods for designing portals mostly rely on two-dimensional drawings and manual calculations, which make it difficult to fully reflect the three-dimensional spatial relationship between the portal and the surrounding terrain and structure, leading to the following main challenges:

[0012] Lack of a 3D interactive design environment: Traditional 2D drawings have limited visualization capabilities and cannot accurately represent the spatial coupling relationship between the portal and the terrain, affecting design accuracy;

[0013] The relationship between the structure and the terrain is complex: Without the assistance of a 3D model, it is difficult to assess the matching degree between the side slope, the lining of the tunnel entrance and the terrain in a timely manner, which can easily lead to discrepancies between the design and the actual situation.

[0014] The design is complex: the design of the portal needs to take into account many parameters such as the station number, the lining of the open tunnel, the side slope, the wall structure, backfilling, and support. Manual adjustment and inspection are time-consuming, labor-intensive, and prone to errors.

[0015] Difficulty in calculating quantities: Currently, the quantity of work at the tunnel entrance is mostly calculated using the cross-sectional method or manual estimation, which is cumbersome and inaccurate, affecting cost control and schedule management.

[0016] The drawings are difficult to produce: two-dimensional drawings cannot intuitively express the complex three-dimensional structure of the portal, which can easily lead to misunderstandings and increase the communication costs between design and construction.

[0017] Therefore, how to efficiently and accurately perform parametric design and visualization of portals and related structures in a three-dimensional digital environment, and realize automated engineering quantity statistics and drawing, has become an urgent technical problem to be solved. Summary of the Invention

[0018] The purpose of this invention is to address the shortcomings of the aforementioned background technology and provide a three-dimensional digital design method for tunnel portals in smart highways. By introducing three-dimensional modeling technology, it achieves precise matching between the portal and the terrain, efficiently performs digital design of all aspects of the portal across all disciplines, and automatically calculates engineering quantities, thereby improving the accuracy and efficiency of drawing.

[0019] The technical solution adopted in this invention is: a three-dimensional digital design method for tunnel portals for smart highways, characterized by the following steps:

[0020] Based on the tunnel design data, the selected portal location is determined, and a three-dimensional ground model of the portal is constructed.

[0021] The form of the tunnel entrance is determined based on its location and the three-dimensional ground model; the tunnel entrance forms include end-wall type, bias-pressure type, and bamboo-cut type.

[0022] The system automatically designs the corresponding parameters based on external instructions and the type of tunnel portal to form an initial design scheme. In the initial design scheme, each type of tunnel portal includes the following general parameters: location, side slope, open-cut lining, open-cut backfill, and intercepting ditch.

[0023] For end-wall type portals, the wall structure parameters are also automatically designed;

[0024] For biased portals, the system automatically designs the wall structure and biased retaining wall structure parameters;

[0025] For bamboo-cut type cave entrances, the system automatically designs the cave entrance construction parameters;

[0026] Adjust the parameters specified in the initial design scheme according to external instructions;

[0027] Based on the revised design scheme, a 3D model of the opening is constructed, and the engineering quantity and drawings are calculated based on the BIM 3D model.

[0028] In the above technical solution, the design order of the above parameters from first to last is: location, lining of the open tunnel, wall structure or opening structure, side slope, backfilling of the open tunnel, and intercepting ditch, wherein the eccentric retaining wall structure is designed simultaneously with the wall structure.

[0029] In the above technical solution, the process of determining the form of the tunnel portal based on its location and the three-dimensional ground model includes:

[0030] At the bottom elevation point of the tunnel lining, after offsetting to the left and right sides by the reserved width, the starting points on the left and right sides are determined.

[0031] Calculate the elevation difference between the starting point and the intersection point with the ground;

[0032] Obtain the inner contour height of the tunnel;

[0033] The portal type is determined based on the comparison between the elevation difference and the inner contour height.

[0034] When the calculation of the elevation difference between the left and right sides is invalid, or when the elevation difference between the left and right sides is less than or equal to the inner contour height, it is determined to be a bamboo-cutting type doorway.

[0035] When the elevation difference on only one side is less than or equal to the height of the inner contour, it is determined to be an eccentric portal.

[0036] When the elevation difference between the left and right sides is greater than the height of the inner contour, it is determined to be an end-wall type portal.

[0037] The process of calculating the quantity of work based on the BIM 3D model in the above technical solution includes:

[0038] Extract the volume of walls and retaining walls from the BIM 3D model to calculate the concrete volume, and extract the length of the steel reinforcement model to calculate the steel reinforcement usage;

[0039] For slopes and uphill slopes, the surface area is extracted from the BIM 3D model and multiplied by the sprayed concrete design thickness to calculate the volume of sprayed concrete, and the number of anchors is calculated according to the anchor arrangement rules.

[0040] Based on the set soil layer thickness, generate earthwork entities and stonework entities below the terrain model in the BIM 3D model. Perform a difference operation between the excavation space enclosed by the end wall, retaining wall, slope, and back slope models and the earthwork and stonework model to obtain the actual excavation entities, and calculate the obtained earthwork and stonework volumes respectively.

[0041] Create a backfill model for the opening and a drainage ditch model behind the wall, and extract the backfill volume and drainage ditch volume from the BIM 3D model based on the model;

[0042] The above calculation results are automatically linked to the bill of quantities field, and the quantities of portal structures, slope protection works, drainage works and earthwork are generated in the prescribed format. When the parameters of the BIM 3D model change, the update is automatically triggered to refresh the relevant quantity data.

[0043] In the above technical solution, the automatic design process of the side slope parameters includes:

[0044] Using the excavation location as the benchmark point for slope calculation, and based on the preset slope ratio and grade height, the slope line is extended outward along the three-dimensional terrain station by station, and the intersection point of the slope line and the terrain is calculated.

[0045] When the calculated height corresponding to any intersection point reaches the graded height, a platform is set at or near the intersection point, and the platform position is used as the new slope calculation benchmark point. The above slope line calculation and judgment process is repeated until a complete slope model is formed on the left, right and up slope directions.

[0046] Boolean operations were performed on the left slope model, right slope model, and uphill slope model to trim overlapping and redundant parts to form a closed area as the excavation model for the tunnel entrance.

[0047] The area below the backfill position in the excavation model is defined as the temporary support range, and the area above the backfill position is defined as the permanent support range. The corresponding support area is calculated based on the excavation model.

[0048] In the above technical solution, the automatic design process of the tunnel lining parameters includes:

[0049] The steps for automatically calculating and determining the recommended length of the tunnel lining include:

[0050] The initial value of the lining length of the open-cut tunnel is set to zero;

[0051] Based on topographic data, engineering design specifications, and the current length of the tunnel lining, the location of the slope initiation point is determined, and then the elevation of the slope initiation point is calculated.

[0052] If the elevation of the starting point is less than the elevation of the top of the tunnel lining, the length of the tunnel lining is increased by a preset step size and the elevation of the starting point of the uphill slope is recalculated.

[0053] When the elevation of the starting point is greater than or equal to the elevation of the top of the tunnel lining, the trial calculation is terminated and the length of the tunnel lining at this time is determined as the recommended value.

[0054] After obtaining the recommended value, the actual lining thickness specified by the user is received, and the lining of the open tunnel is stretched and laid out along the direction perpendicular to the reference plane using the set standard cross-section as the reference plane to generate a three-dimensional open tunnel lining model.

[0055] In the above technical solution, the backfill parameters for the open channel are designed sequentially from bottom to top:

[0056] The height of the left and right sides of the bottom backfill and the bottom backfill material are determined according to external instructions;

[0057] The backfill material for the middle section will be determined based on external instructions.

[0058] In top backfill design, the backfill profile is automatically calculated and adjusted through the following steps:

[0059] The shape of the top backfill is defined by the width of the left and right sides of the tunnel wall, and the intersection of the top backfill layer and the side slope is calculated to form the initial backfill shape.

[0060] Provides the ability to add line segment vertices, allowing the initial backfill shape line segment to be broken at any position where adjustment is needed;

[0061] Whenever a line segment vertex is added, the connection relationship and direction of the backfill shape are updated in real time, and the backfill contour is refined to ultimately form a top backfill shape that meets the requirements of mountain stability and drainage.

[0062] In the above technical solution, the automatic design process of the intercepting ditch parameters includes:

[0063] Obtain the intersection data of the slope model and the terrain, and generate a three-dimensional polyline representing the initial layout line of the intercepting ditch;

[0064] The three-dimensional polyline is projected onto a horizontal plane to obtain a projection line;

[0065] According to the preset offset rules, the projection line is offset away from the opening to obtain the offset line;

[0066] The offset line is then projected onto the three-dimensional terrain to generate the preliminary layout line of the intercepting ditch.

[0067] The intercepting ditch layout line is updated according to external instructions, and a solid model of the intercepting ditch is generated based on the selected cross-sectional shape of the intercepting ditch.

[0068] In the above technical solution, the automatic design process of the wall structure parameters includes:

[0069] The sum of the tunnel cross-sectional shape and height, the thickness of the open-cut lining, the lining depth, and the reserved height is taken as the initial height of the end wall;

[0070] Based on the tunnel width and road width information, the coordinates of the excavation positions on both sides are determined, and combined with the preset slope ratio, the intersection points of the left and right slopes and the road surface are calculated, thereby obtaining the actual width of the end wall.

[0071] Based on the top elevation of the wall, topographic undulations, and slopes of both sides, the width and height range of a single top step are defined; using 3D modeling technology, the intersection position between the top backfill and the end wall is calculated; based on the intersection position and the overall stability requirements of the end wall, the number of top steps and the start and end coordinates of each step are determined.

[0072] Based on the measurement data of the intersection of the wall and the terrain and the requirements of engineering mechanics, the range of values ​​for the width and height of a single bottom step is defined, and the number of bottom steps and the arrangement of each step are calculated according to the length and height difference of the intersection of the wall and the terrain on both sides.

[0073] In the above technical solution, the automatic design process of the bias retaining wall parameters includes:

[0074] Choose the location of the retaining wall on the plane;

[0075] Based on the intersection of the ground line and the top of the retaining wall, determine whether the retaining wall should be separated from the lining of the open tunnel, and calculate the recommended value for the separation width;

[0076] Calculate the intersection point between the retaining wall and the terrain on the side of the retaining wall furthest from the end wall, and determine the length of the retaining wall through this intersection point.

[0077] The beneficial effects of this invention are: by automatically determining the form of the tunnel portal and generating corresponding parameters, this invention reduces the tedious steps of traditional two-dimensional design that rely on manual judgment; by intuitively presenting the relationship between the tunnel portal and the terrain in a three-dimensional environment, it helps to discover and correct potential design problems in a timely manner; automated design can avoid errors caused by manual estimation, improve the matching degree between the tunnel portal and the actual terrain, and reduce safety hazards; based on the initial design scheme, parameters can be flexibly adjusted according to external instructions to meet real-time needs on site.

[0078] Furthermore, this invention clarifies the design sequence of parameters: first, location; then, lining of the opening; next, wall / opening structure; side slope; backfilling of the opening; and drainage ditch. The eccentric retaining wall and wall structure are designed simultaneously. By specifying the order, the interconnected components are designed in stages, reducing repeated modifications. The lining of the opening, wall / opening structure, side slope, backfilling, and drainage ditch all have sequential dependencies, and this order helps to ensure accurate connection in the model. Designers can divide tasks according to a fixed process, avoiding conflicts caused by confusion in steps between different disciplines.

[0079] Furthermore, this invention directly extracts the volume of solids such as walls and retaining walls, as well as the length of reinforcing steel models, from the BIM 3D model, eliminating the need for manual measurement or discrete section estimation. The calculation accuracy reaches the level of the model itself, significantly outperforming the 15%–30% error of traditional section methods. Based on pre-set parameters, it automatically calculates the quantities of concrete, reinforcing steel, shotcrete, and anchor bolts; it automatically generates the excavation volume and separates earthwork and rock excavation through Boolean difference operations; it automatically constructs backfill and drainage ditch models and extracts their volumes. A single run outputs a complete set of engineering quantity data, completely freeing designers from tedious manual quantity calculations. By generating earthwork and rockwork entities separately below the terrain and performing difference operations with the opening component model, this invention can separately accumulate the volumes of earthwork and rockwork, achieving refined statistics and optimized resource allocation for both types of materials, providing more accurate data support for construction plans and cost budgets. When geometric parameters in the BIM model (such as soil thickness, slope gradient, component dimensions, etc.) are adjusted, the calculation process can automatically rerun the relevant quantity calculation modules and refresh the reports without manual secondary operations. This ensures that the engineering quantity data remains synchronized with the model after design changes, shortening the design iteration cycle. Various engineering quantities (portal structures, slope protection works, drainage works, earthwork) are automatically mapped to existing standard bill of quantities fields and categorized and summarized according to the standard format, directly generating complete reports that can be used for bidding and cost accounting. This reduces the workload of subsequent processing and proofreading, and helps with project management and decision-making.

[0080] Furthermore, this invention automatically determines the portal type by comparing the elevation difference between the left and right sides with the tunnel's internal contour height: if both are less than or equal to the elevation difference, it is a bamboo-cutting type; if only one side is less than or equal to the elevation difference, it is an eccentric type; if both sides are greater than the elevation difference, it is an end-wall type. This transforms human experience into executable elevation difference comparison logic, significantly reducing human judgment errors. The elevation difference between the left and right sides can reflect different terrain undulations, quickly selecting the most suitable portal type. This avoids the need for extensive trial and error in the early design stages, providing portal type suggestions based on the terrain in one go.

[0081] Furthermore, this invention automatically picks up the tunnel entrance station number and automatically calculates the station number at the boundary between open and closed tunnels, avoiding repetitive operations and human error; the location parameters are uniformly managed within the system and can be shared with other design parameters to ensure the accuracy of the overall design data; if the length of the open tunnel changes, the station number at the boundary between open and closed tunnels can be automatically updated, improving flexibility.

[0082] Furthermore, this invention can accurately simulate terrain undulations by calculating intersections and determining graded heights for each station number; Boolean operations form closed areas, intuitively reflecting the actual construction scope; and it automatically distinguishes between temporary and permanent support areas, facilitating project quantity statistics and construction arrangements.

[0083] Furthermore, this invention can automatically find the "optimal" or "most suitable" length of the tunnel based on the terrain and design specifications, reducing blind experimentation; it encapsulates structural elements such as manual drawing and reinforcement into standard cross-sections, and quickly generates a three-dimensional model through stretching and layout; after obtaining the recommended value, users can fine-tune the thickness or length according to the site conditions, balancing efficiency and flexibility.

[0084] Furthermore, this invention separates the backfill into bottom, middle, and top sections to ensure that each layer can be designed according to actual materials and height requirements; the initial backfill shape is formed by intersection calculation, and then refined by line segment vertex insertion, taking into account both the mountain's water catchment and drainage; the backfill shape is more in line with the terrain and drainage requirements, reducing the risk of flooding or landslides.

[0085] Furthermore, this invention utilizes offset and projection algorithms to ensure that a preset safe distance is maintained between the intercepting ditch and the side slope; the intercepting ditch effectively intercepts mountain runoff, reducing the risk of surface water leakage or erosion during construction; it eliminates the need for manual measurement and repeated testing, significantly improving design and construction efficiency.

[0086] Furthermore, this invention incorporates elements such as end wall height, width, top step, and bottom step into the same calculation framework to improve the overall structural stability; it rationally arranges the number and size of steps to reduce unnecessary earthwork excavation while ensuring reasonable stress on the wall body; and it considers the intersection of backfill when calculating the top step, making the connection between the end wall and the backfill tighter.

[0087] Furthermore, this invention provides an automated design process to address the need for side retaining walls to resist unbalanced earth pressure in eccentrically oriented tunnel portals. By calculating the terrain intersections and separation widths, it ensures that the retaining wall and the tunnel lining can be reasonably connected, reducing construction problems caused by differences in site terrain. It can determine whether the retaining wall should be separated from the tunnel lining based on the actual situation and automatically recommend the separation width, taking into account both construction convenience and structural safety. Attached Figure Description

[0088] Figure 1 This is a schematic diagram of the process of the present invention;

[0089] Figure 2 This is a schematic diagram of the portal structure;

[0090] Among them, 2.1 - tunnel portal, 2.2 - ground line, II - tunnel centerline;

[0091] Figure 3 Schematic diagram of parameters for various types of portals;

[0092] Figure 4 This is a diagram of an end-wall type;

[0093] Figure 5 This is a schematic diagram of a biased portal.

[0094] Figure 6 This is a schematic diagram of a bamboo-carved doorway.

[0095] Figure 7 This is a schematic diagram of the slope.

[0096] Among them, 7.1 - left side slope, 7.2 - right side slope, 7.3 - uphill slope, 7.4 - three-dimensional terrain;

[0097] Figure 8 Schematic diagram of the design concept for the slope;

[0098] Figure 9 This is a schematic diagram of the backfilling of the Myeongdong (mysterious cave).

[0099] Among them, 9.1 - bottom backfill, 9.2 - middle backfill, and 9.3 - top backfill;

[0100] Figure 10 This is a schematic diagram of the intercepting ditch;

[0101] Among them, 10 is the intercepting ditch;

[0102] Figure 11 This is a schematic diagram of the wall structure.

[0103] Wherein, L1 - left side width, L2 - right side width, H0 - wall height, 11.1 - top step, 11.2 - bottom step;

[0104] Figure 12 A schematic diagram showing the design parameters for the wall outline;

[0105] Among them, 12.1 - top outline, 12.2 - left outline, 12.3 - right outline;

[0106] Figure 13 This is a schematic diagram showing the distribution of design parameters for the retaining wall. Detailed Implementation

[0107] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments to facilitate a clear understanding of the present invention, but these descriptions do not constitute a limitation on the present invention.

[0108] Example 1

[0109] like Figure 1 As shown, this invention provides a three-dimensional digital design method for tunnel portals in smart highways, comprising the following steps:

[0110] Based on the tunnel design data, the selected portal location is determined, and a three-dimensional ground model of the portal is constructed.

[0111] The form of the tunnel entrance is determined based on its location and the three-dimensional ground model; the tunnel entrance forms include end-wall type, bias-pressure type, and bamboo-cut type.

[0112] The system automatically designs the corresponding parameters based on external instructions and the type of tunnel portal to form an initial design scheme. In the initial design scheme, each type of tunnel portal includes the following general parameters: location, side slope, open-cut lining, open-cut backfill, and intercepting ditch.

[0113] For end-wall type portals, the wall structure parameters are also automatically designed;

[0114] For biased portals, the system automatically designs the wall structure and biased retaining wall structure parameters;

[0115] For bamboo-cut type cave entrances, the system automatically designs the cave entrance construction parameters;

[0116] Adjust the parameters specified in the initial design scheme according to external instructions;

[0117] Based on the revised design scheme, a 3D model of the opening is constructed, and the engineering quantity and drawings are calculated based on the BIM 3D model.

[0118] This embodiment specifically includes the following steps:

[0119] Step S1: Load and parse the basic data required for the 3D design of the tunnel portal, including route, terrain, and overall tunnel design information. Based on the tunnel body, obtain the route data for the design line. Construct a 3D ground model around the portal, and based on the terrain foundation, extract the terrain point set within the boundary range to construct a mesh-based 3D terrain.

[0120] The route data includes the horizontal and vertical profiles of the route where the tunnel is located, the ground line of the cross section, the ground line of the longitudinal profile, and the road width template of the standard section.

[0121] The terrain data refers to the basic data for constructing the three-dimensional terrain of the tunnel site area, which is stored in the form of point sets. The data source can be obtained from the ground line of the cross section of the route, or from the contour lines, elevation points or feature lines of the topographic map, and uniformly converted into point sets.

[0122] The overall tunnel design information includes the construction clearance and outline, standard cross-section, tunnel form, open-cut lining structure, tunnel portal station number, and open-cut lining length. This information is generally initially arranged during the route and overall design phases, and detailed design is carried out based on this information.

[0123] Specifically, firstly, based on the route type (including integral and separated types) and the tunnel cross-section settings (including integral, separated, continuous arch, and bifurcated types), the number and form of tunnel portal design objects are determined. Then, based on the tunnel body, the route data for the design line is obtained. Based on the overall tunnel design information, the station number of the portal is obtained. Based on the station number and design line, the spatial coordinates of the portal are calculated. Based on the portal's spatial coordinates, the boundary of the required terrain around the portal is calculated. Based on the terrain data, the set of terrain points within the boundary area is extracted, and a 3D mesh terrain is constructed.

[0124] Step S2: Based on the location and surrounding terrain, determine the type of the entrance.

[0125] The types of entrances include three categories: end-wall type, bias-pressure type, and bamboo-cut type.

[0126] Obtain the tunnel entrance station number. According to the slope design rules (detailed parameters for the tunnel entrance object are explained in S6), from the bottom elevation point of the open-cut tunnel lining, such as... Figure 2 As shown, calculate the starting point P0 on the left and right sides after offsetting the construction reserved width 'a', respectively, and find the intersection point Pi on the ground. Record the elevation corresponding to point Pi. Compare the elevations of the intersection points on the left and right sides. Elevation of the starting point The elevation differences corresponding to the left and right sides were obtained respectively. and :

[0127]

[0128] Obtain the inner contour height H in the standard cross-section determined in S1.

[0129] The portal type is determined based on the comparison between the elevation difference and the inner contour height.

[0130] When the calculation of the elevation difference between the left and right sides is invalid, or when the elevation difference between the left and right sides is less than or equal to the inner contour height, it is determined to be a bamboo-cutting type entrance. Figure 6 As shown;

[0131] When the elevation difference on only one side is less than or equal to the height of the inner contour, it is determined to be an eccentric portal. Figure 5 As shown;

[0132] When the elevation difference between the left and right sides is greater than the height of the inner contour, it is determined to be an end-wall type portal. Figure 4 As shown.

[0133] Step S3: Based on the terrain and environment, execute an automatic algorithm program to recommend some portal design parameters and form an initial design scheme.

[0134] The aforementioned portal design parameters refer to the parameters for three types of portals: end-wall type, bias-pressure type, and bamboo-cut type.

[0135] The design parameters for the three types of tunnel portals are divided into two categories: common and unique. The common parameters include location, side slope, open-cut lining, open-cut backfill, and drainage ditch.

[0136] End-wall type wall structure;

[0137] Bias-based reinforcement of wall and retaining wall structures;

[0138] The opening was constructed by cutting bamboo.

[0139] The parameters of the three types of portals are as follows: Figure 3 As shown.

[0140] like Figure 1 As shown, the design sequence of the above parameters from first to last is: location, tunnel lining, wall structure or bamboo-cutting tunnel opening structure, side slope, tunnel backfill, and intercepting ditch. The eccentric retaining wall structure is designed simultaneously with the wall structure.

[0141] Specifically, the location includes the tunnel entrance station number, the length of the open tunnel, and the station number at the boundary between the open and closed sections. The tunnel entrance station number is taken from S3, indicating the outermost station number of the tunnel lining; the length of the open tunnel is specified by the designer; the station number at the boundary between the open and closed sections is the tunnel entrance station number plus the length of the open tunnel.

[0142] Specifically, the slope includes a left side slope 7.1, a right side slope 7.2, and a slope 7.3, as shown below. Figure 7 As shown. The design calculation method for the side slope and back slope involves setting specific slope rules and calculating the three-dimensional terrain starting from the slope base point to obtain the slope result. The specific calculation process involves sequentially performing operations according to each station number to ultimately obtain complete data on the left side slope, right side slope, and back slope. The design concept of the side slope and back slope in this embodiment is as follows: Figure 8 As shown, the key parameters involved in the slope protection include the slope protection principle, slope protection results, and support scheme. The slope protection and model construction steps are as follows:

[0143] (1) Determine the benchmark point and initial calculation: The excavation location is used as the benchmark point for slope calculation. Based on the established slope ratio and graded height, the intersection point calculation is started on the three-dimensional ground. This calculation process is based on three-dimensional terrain data. Starting from the benchmark point of the pile design line, the extension trajectory of the slope on the ground is solved according to the slope ratio, and then the position of the first calculation intersection point is obtained.

[0144] (2) Grading Height Judgment and Platform Setting: During the calculation process, the calculated height of the intersection point is monitored in real time. When the calculated height reaches the preset grading height, the current slope calculation is stopped. A platform is set at this location based on a pre-set specific width and slope. The platform width and slope are determined according to the actual needs of the project and relevant design specifications to ensure the stability of the slope and the convenience of construction.

[0145] (3) Model building loop: Using the set platform as the new reference point, repeat the operations of steps 1 and 2. Continue to calculate the intersection point with the three-dimensional ground according to the slope ratio. When the graded height is reached again, set the platform again. Repeat this loop until the slope calculation of the entire slope or back slope in this direction is completed. Through this process, the left slope model, the right slope model and the back slope model are built respectively.

[0146] (4) Boolean Operations and Excavation Model Formation: Boolean operations are performed on the completed left slope model, right slope model, and invert slope model. Boolean operations, through specific mathematical logic, trim overlapping parts and excess portions beyond actual requirements from the three models. The enclosed area formed after Boolean operations and trimming is the excavation model. This three-dimensional excavation model can clearly and intuitively present the actual conditions of the tunnel entrance slope and the location of the mountain excavation after slope laying, effectively solving the unclear and inaccurate problems in current slope design calculations, and providing designers with comprehensive and accurate design references.

[0147] Furthermore, users can set up slope support schemes according to actual needs. Generally, the backfill location serves as the boundary; temporary support is used for areas below the backfill, while permanent support is used for areas above the backfill. Using the completed 3D model, the area corresponding to different support schemes can be accurately calculated, providing detailed and reliable data support for subsequent engineering quantity statistics and effectively ensuring the accuracy of project budget preparation and construction resource allocation.

[0148] Specifically, the lining of the open tunnel refers to the lining structure from the tunnel entrance station number to the station number at the boundary between the open and closed sections. This lining structure is constructed based on the standard cross-section agreed upon in S1, which includes specific geometric shapes, dimensional parameters, and structural reinforcement design elements.

[0149] In the actual construction of the tunnel lining, the user specifies the lining thickness according to the actual project requirements. After the thickness is specified, the specific shape of the tunnel lining is obtained through a stretching and lofting operation. The stretching and lofting process is as follows: using the standard cross-section as the reference plane, according to the user-specified thickness value and the recommended length of the tunnel lining, the lining is stretched uniformly along a direction perpendicular to the reference plane, thereby forming a three-dimensional tunnel lining model with a specific length and thickness.

[0150] The recommended value for the lining length of the tunnel is a key parameter, and its automatic calculation steps are as follows:

[0151] (1) Initial settings: In the initial stage of calculation, the initial value of the tunnel lining length is set to 0. At the same time, the required topographic data is prepared, including topographic contour information, elevation data of various points on the ground, and parameters and constraints specified in relevant engineering design specifications.

[0152] (2) Calculation of the starting point of the slope: Based on the currently set length of the tunnel lining, combined with the terrain data and engineering design specifications, the location of the starting point of the slope is determined. This algorithm takes into account factors such as the design slope of the tunnel and the connection requirements with the surrounding terrain, and calculates the coordinates of the starting point in the terrain coordinate system.

[0153] (3) Elevation judgment: Calculate the elevation of the starting point of the slope through the design line and compare it with the height of the open tunnel. If the calculated elevation of the starting point is less than the height of the open tunnel, it indicates that the height of the slope is insufficient to completely cover the open tunnel according to the currently set lining length of the open tunnel; if the elevation of the starting point is greater than or equal to the height of the open tunnel, proceed to the next step of judgment.

[0154] (4) Length adjustment and cycle: When the elevation of the starting point is less than the height of the tunnel, the length of the tunnel lining needs to be further increased. The increased length is adjusted according to the preset step size, for example, by 0.5 meters each time. After adjustment, return to step 2, recalculate the position of the starting point and related elevation data, and perform a new round of elevation judgment, and repeat this cycle.

[0155] (5) Trial Calculation Termination: After repeated trial calculations, the trial calculation process terminates when the elevation of the intersection point of the slope and the terrain is precisely equal to the elevation of the top of the tunnel. The tunnel lining length L determined at this point is the recommended value obtained through automatic calculation. After obtaining the recommended value, the user may further adjust the recommended value of the tunnel lining length according to the actual conditions of the project site, such as the distribution of surrounding buildings and subtle differences in geological conditions.

[0156] Specifically, in tunnel engineering, backfilling of the open-cut tunnel is a crucial step in ensuring the stability of the surrounding mountains. Open-cut tunnel backfilling is suitable for end-wall type, eccentric pressure type, or bamboo-cut type tunnel entrances. The work area is the excavation space enclosed by the open-cut tunnel lining and the side slopes, and the backfilling sequence is from bottom to top. For example... Figure 9 As shown, the backfilling of the tunnel mainly consists of three parts: the bottom, the middle, and the top.

[0157] (1) Bottom backfill 9.1: Attention should be paid to the backfill height on the left side, the backfill height on the right side, and the selection of bottom backfill material. The above parameters are obtained by manual input by the user.

[0158] (2) Middle backfill 9.2: The key is to select appropriate backfill materials. The above parameters are obtained by manual input by the user.

[0159] (3) Top backfill 9.3: This involves the selection of backfill materials (the above parameters are obtained by manual input by the user) and the design of the backfill shape.

[0160] During the design process, the bottom, middle, and top sections are designed sequentially from bottom to top. In the top backfill design, the backfill outline is automatically calculated and performed according to the following steps:

[0161] (1) Initial shape definition: The shape of the top backfill 9.3 is defined by the width of the left side and the width of the right side of the wall, dividing it into left backfill and right backfill. The shape is defined by line segments, and the initial value of the offset (x,y) of each point is set to (0,0). At the same time, the intersection of the top backfill layer and the slope is calculated, and the shape formed by connecting these intersections is used as the initial shape of the top backfill outline.

[0162] (2) Detailed design preparation: Based on the determined initial values, the user prepares to make detailed adjustments to the backfill shape. The system provides the function of adding line segment vertices Pi to prepare for the subsequent breaking of shape line segments.

[0163] (3) Refined shape adjustment: Users can add line segment vertices Pi to break the original shape line segments at the positions where adjustments are needed. Each time a vertex Pi is added, the system recalculates the line segment connection relationship and changes the shape direction, thereby gradually refining the backfill shape design to achieve a top backfill shape design that meets the requirements of smooth drainage of mountain water.

[0164] Specifically, the intercepting ditch 10 plays a crucial role in tunnel construction. Before excavating the slope, an intercepting ditch must be installed in advance outside the toe of the slope, such as... Figure 10 As shown, its main function is to intercept mountain runoff, providing a solid guarantee for safety during construction. This embodiment relies on a slope model to accurately calculate the actual slope location, thereby achieving accurate setting of the intercepting ditch 10 and greatly improving construction precision. Automatic calculation process for the intercepting ditch layout line:

[0165] (1) Generate the initial three-dimensional polyline: By determining the intersection points of the slope and the back slope with the terrain, a three-dimensional polyline represented by Li(x,y,z) is constructed.

[0166] (2) Obtaining the horizontal projection: According to the construction specifications, the intercepting ditch 10 usually needs to be located 5m outside the side slope. Therefore, it is necessary to calculate the projection of each vertex of Li on the horizontal plane to obtain Lp(x,y).

[0167] (3) Calculate the offset value: According to the design requirements of the intercepting ditch 10, determine the offset value of the intersection line between the intercepting ditch 10 and the side slope, and determine the offset value of each projection point in the direction away from the opening, denoted as Lq(x,y).

[0168] (4) Projection to generate the layout line: Project the offset points onto the terrain again to obtain Lj(x,y,z), which is the offset three-dimensional polyline, that is, the preliminary layout line of the intercepting ditch.

[0169] (5) User optimization and model generation: Users can further adjust and optimize Li according to the actual situation to obtain the final intercepting ditch layout line. In addition, based on the cross-sectional shape of the intercepting ditch selected by the user, the intercepting ditch physical model can be generated to provide an intuitive and accurate reference for construction.

[0170] Specifically, the wall structure refers to the structure of the end wall, which is designed separately for the elevation, section, top steps, bottom steps, drainage ditch, and nameplate. The design process for the drainage ditch is as described above.

[0171] like Figure 11 As shown, the external contour of the end wall is defined by elevation parameters, which include the wall height, left width, and right width. The wall height is measured at the location of the tunnel centerline.

[0172] Meanwhile, to fully define the structure of the tunnel end walls along the route, the end wall profile includes two key parameters: end wall slope and end wall thickness, which are manually set values. The end wall slope determines the degree of inclination of the end wall along the route, and its value affects the overall stability of the end wall and its connection with the surrounding terrain and structure; the end wall thickness is related to the end wall's load-bearing capacity and retaining effect, and needs to be determined based on the actual stress conditions of the project and relevant specifications.

[0173] To meet the retaining function requirements of the end wall, and to minimize its size, reduce project costs, and ensure its harmony with the terrain, a stepped design is implemented at the top of the end wall. Step parameters include the number of steps and the dimensions of each step. Simultaneously, to reduce excavation during construction at the bottom of the wall and further lower project costs, steps are also installed at the bottom. The bottom steps are divided into left and right steps, and their parameters also include the number of steps and the dimensions of each step.

[0174] like Figure 12 As shown, the automatic calculation method for end wall parameters and steps is as follows:

[0175] (1) Calculation of end wall height: Based on the tunnel cross-section shape height H1, plus the open tunnel lining thickness H2, plus the lining depth H3, and the reserved height H4, the wall height H0 is calculated. The calculation formula is H0=H1+H2+H3+H4.

[0176] (2) Calculation of wall width: First, calculate the position coordinates of the excavation on both sides based on the tunnel width and road width information. Then, based on the given slope, calculate the intersection position of the slope on both sides with the road surface, determine the height of the left and right sides of the tunnel entrance, and thus determine the wall width.

[0177] (3) Calculation of parameters for the top step 11.1:

[0178] a) Definition of Step Foundation Dimensions: A comprehensive analysis of the actual elevation of the top of the wall, terrain undulation data, and the slope and direction of both sides. Based on this data, and according to the default width bi and height hi of the i-th step i. For example, based on pedestrian accessibility and structural stability, the preset range of values ​​for width bi and height hi is used; the specific values ​​need to be precisely determined according to the actual engineering conditions.

[0179] b) Intersection Location Calculation: Using 3D modeling technology, the design model of the top backfill and the end wall model are integrated to calculate the intersection location between the top backfill and the wall. This algorithm fully considers the physical properties of the backfill material and the influence of the backfill construction process on the final shape, accurately determining the spatial coordinates of the intersection.

[0180] c) Determining the Step Layout: Based on the calculated intersection locations, and taking into account factors such as the overall stability of the end wall, aesthetic harmony with the terrain, and construction feasibility, the top steps are rationally arranged. Simultaneously, according to the specific circumstances of the intersection locations, the user determines the starting and ending positions of each step level based on the 3D rendering, to achieve good harmony between the end wall and the terrain, while also meeting the requirements for reducing scale and lowering costs.

[0181] (4) Calculation of parameters for the bottom step 11.2:

[0182] a) Basic Dimension Definition: A detailed analysis is conducted on the intersections of the wall with the terrain on both sides, and the precise coordinate data of the intersection points are calculated. Based on actual engineering requirements and mechanical principles, the width *bi* and height *hi* of the *i*-th step are defined. The width *bi* needs to consider the operating space for construction machinery and the load-bearing capacity of the wall's base, while the height *hi* needs to be determined based on changes in terrain slope and foundation stability requirements. A range of values ​​is set according to engineering needs, with the specific values ​​depending on the actual engineering situation.

[0183] b) Step Count Calculation: Based on the defined step width and height, as well as the length and height difference between the two sides of the wall and the terrain, the number of steps is calculated by rounding down the ratio of the wall height to the step height. This algorithm fully considers the error range during construction and the irregularity of the terrain, ensuring that the calculated number of steps meets the requirements of reducing excavation while guaranteeing the stability of the wall's bottom structure.

[0184] Specifically, the biased portal is based on the end-wall portal, with a retaining wall arranged along the direction of the open-cut lining. Its function is to block the lateral soil, thereby ensuring the stability of the structure.

[0185] like Figure 13 As shown, the specific parameters of the retaining wall are as follows:

[0186] (1) Horizontal positioning point: There are two setting methods. When the combined setting is used, the vertical wall and the inner edge of the lining are kept flush; if the separate setting is used, the offset is added to the base position of the combined setting.

[0187] (2) Vertical positioning point: The distance from the bottom of the wall to the design elevation is used as the positioning reference.

[0188] (3) Dimensional parameters: including total height H, bottom width B, top width b, bottom slope i, root height h and root height and width d.

[0189] The automated design process for retaining walls is as follows:

[0190] (1) Retaining wall configuration decision: First, the user command selects a lining template for an open tunnel. Based on the selection result of the tunnel portal type, it is determined whether a retaining wall needs to be configured.

[0191] (2) Determining the location of the retaining wall: After determining the configuration of the retaining wall, the designer shall determine the offset distance of the retaining wall on the plane.

[0192] (3) Separation setting judgment and width recommendation: Based on the intersection of the ground line and the top of the retaining wall, if there is an intersection, it is determined that the retaining wall and the open-cut lining should be set together, and a suitable separation setting width recommendation value is given.

[0193] (4) Determining the length of the retaining wall: After determining the lateral position of the retaining wall, calculate the intersection point between the side of the retaining wall away from the end wall and the terrain. Determine the length of the retaining wall through this intersection point to ensure that the retaining wall can effectively resist lateral soil pressure and reasonably control the construction cost while meeting the engineering requirements.

[0194] Step S4: In the 3D visualization environment, the designers adjust the detailed parameters based on the initial design scheme to complete the detailed design of the portal.

[0195] Step S5: Generate a BIM 3D model based on the adjusted design scheme. Calculate the quantities of work required for the opening using the BIM 3D model. These quantities include the volume of excavated earthwork, concrete for the walls, concrete for the drainage ditches, backfill for the open opening, the protected area, the excavation volume of the intercepting ditch, and the amount of concrete used. Specifically, this includes the following steps:

[0196] Step S5.1: Create the engineering model of the tunnel entrance. Calculate the quantities of the end wall, eccentric retaining wall, and bamboo-cutting entrance based on the model volume. Among these,

[0197] The specific process for modeling and calculating the quantities of the end wall portal is as follows:

[0198] 1) Parameter definition: The main parameters of the end wall opening model include wall height, left side width, right side width, top step setting, bottom step setting, wall thickness, and slope.

[0199] 2) Modeling method: Based on the above parameters, construct a three-dimensional solid model of the end wall in the BIM platform; generate the main structure of the wall through Boolean operations.

[0200] 3) Calculation of project quantities:

[0201] The concrete volume is calculated by directly extracting the solid volume data of the end wall in the BIM model;

[0202] Based on the length of the main bars and stirrups in the steel reinforcement model, statistics are compiled according to the steel reinforcement type (HRB400, HPB300, etc.); the total amount of steel reinforcement is calculated according to the standard weight per meter of steel reinforcement (e.g., 2.47 kg / m for Φ20 steel reinforcement).

[0203] The specific process for modeling and calculating the quantities of the eccentric retaining wall is as follows:

[0204] 1) Parameter definition: The parameters of the bias retaining wall include bottom width, top width, wall height, and slope, which are set in segments along the longitudinal direction of the route.

[0205] 2) Modeling method: Generate a single-segment retaining wall model based on the cross-sectional parameters (bottom width, top width, wall height, slope); splice the retaining wall model in segments along the route to ensure continuous matching of parameters in each segment.

[0206] 3) Calculation of project quantities:

[0207] Extract the solid volume of each retaining wall segment from the BIM model and sum them up to obtain the total volume of concrete.

[0208] Extract the reinforcement layout information (spacing of main bars and density of stirrups) according to the retaining wall segments; calculate the total amount of reinforcement used by combining the reinforcement specifications and the standard weight per linear meter.

[0209] The specific calculation process for modeling and calculating the quantity of work at the bamboo-cutting cave entrance is as follows:

[0210] 1) Parameter definition: The parameters of the bamboo cutting hole include length, cutting slope and tangent angle, which are suitable for places with gentle ground slope.

[0211] 2) Modeling method: Generate a three-dimensional solid model of the bamboo section based on the cutting slope and the tangent angle; perform Boolean shearing on the bamboo section and the main structure of the end wall to obtain the final model.

[0212] 3) Calculation of project quantities:

[0213] Extract the solid concrete volume of the area where the bamboo section connects to the opening in the BIM model;

[0214] The arrangement length and specifications of the steel mesh on the surface of the bamboo cuttings are statistically analyzed; the total amount of steel reinforcement is calculated based on the standard weight per linear meter.

[0215] Step S5.2: Create a side slope model and calculate the earthwork volume of the tunnel entrance and the side slope volume.

[0216] Step S5.2.1 Create slope and invert surface models:

[0217] 1) Parameter definition: including geometric parameters and engineering parameters. Geometric parameters: including slope (e.g., 1:1~1:0.5), graded height (e.g., each grade ≤8m, segments exceeding 8m with steps), step width (1~3m), step slope (0~1:0.2), and starting point location (2~4m from the edge of the arch foot of the tunnel lining).

[0218] Engineering parameters: Temporary protection scheme (including shotcrete and anchor support, etc.); Permanent protection scheme (including anchor frame beams, etc.).

[0219] 2) Modeling method: Input the slope ratio and grade height, and slope from the starting point to the terrain surface. The intersection line between the slope and the original terrain is automatically calculated. A multi-level step structure is generated according to the step width and step slope ratio. The slope, back slope model and the end wall and retaining wall model are subjected to three-dimensional Boolean operation to eliminate overlapping areas. The joints are smoothed (curvature radius ≥ 1m).

[0220] Step S5.2.2: Calculate the slope protection work volume:

[0221] 1) Area extraction: Extract the slope surface area S from the model. 边坡 (Accuracy ±0.1㎡);

[0222] 2) Calculation of project quantity:

[0223] Volume of shotcrete with wire mesh: V 喷混凝土 =S 边坡 •h (h is the designed thickness of the spray layer);

[0224] Number of anchor bolts: N 锚杆 =⌈S边坡 / 4⌉ (Calculated based on a 2m×2m spacing).

[0225] Step S5.2.3: Calculate the amount of slope protection work.

[0226] 1) Area extraction: Extract the slope surface area S from the model. 仰坡 (Accuracy ±0.1㎡);

[0227] 2) Calculation of project quantity: Volume of shotcrete with wire mesh: V 喷混凝土 =S 仰坡 •h (h is the design thickness of the sprayed layer); Number of anchor bolts: N 锚杆 =S 仰坡 / 4 (calculated based on a 2m×2m spacing).

[0228] Step S5.2.4: Calculate the volume of excavated earthwork:

[0229] In the traditional cross-section method, the calculation of excavated earthwork volume has a large deviation. In this embodiment, the solid volume method is used instead of the cross-section method, which significantly improves both accuracy and efficiency. The specific steps include:

[0230] 1) Soil layer thickness setting: Based on the user-defined soil layer thickness H 土 (0~5m), generate an earthwork solid model (extending downwards from the terrain surface H). 土 The lower layer automatically generates a stone solid model.

[0231] 2) Boolean operation to find the intersection: Perform a difference operation between the excavation space enclosed by the end wall, retaining wall, side slope, and back slope and the earthwork model to obtain the actual excavation body; separate the earthwork and rockwork intersection entities (interface tolerance ≤ 0.05m).

[0232] 3) Volume calculation:

[0233] Earthwork volume: V 土 =∑V 土方交集 ;

[0234] Stone volume: V 石 =∑V 石方交集 ;

[0235] Total excavation volume: V 总 =V 土 +V 石 (Volume accuracy ±0.5m³).

[0236] Step S5.3: Create a layered backfill model for the open channel and calculate the backfill volume for each layer; the backfill model includes a backfill layer and a cover layer:

[0237] 1) Parameter definition:

[0238] Geometric parameters: number of backfill layers (2 or 3 layers); backfill height of each layer (2m for the first layer, 1m for the second layer); thickness of the cover layer (0.3~0.5m); profile segment parameters (single segment length 5~10m, elevation difference ±0.5m); longitudinal slope (5%~15%).

[0239] Engineering parameters: Backfill material (plain concrete, crushed stone, etc.); Covering material (waterproof clay, concrete, etc.).

[0240] 2) Modeling methods:

[0241] Cover layer modeling: Determine the outline of the cover layer, using the center of the top of the end wall as the positioning point, define outline segments to the left and right respectively, input the length and height difference of each segment, and generate the cover layer baseline; extend radially from the baseline to the uphill slope according to the longitudinal slope, and cut off after intersecting with the uphill slope surface to generate the cover layer surface; extrude the surface according to the cover layer thickness (0.3~0.5m) to generate a three-dimensional solid model.

[0242] Backfill layer modeling: Starting from the base of the 3D solid model of the overburden layer, backfill bodies are generated layer by layer according to the layer height (2m for the first layer, 1m for the second layer); Boolean difference set operation is performed on each backfill body with the end wall, slope, side slope and open tunnel lining to remove the overlapping parts (tolerance ±0.05m), and the backfill models of each layer are obtained in sequence.

[0243] 3) Calculation of project quantities:

[0244] Backfill layer quantity: Extract the volume of each backfill layer, Vbackfill layer, and calculate the material usage based on the material density (1.8t / m3 for crushed stone and soil, and 2.0t / m3 for sand and gravel): Wmaterial = Vbackfill layer ⋅ ρmaterial

[0245] Cover layer quantity: Extract the solid volume V of the cover layer and output the result according to the material type (such as concrete volume).

[0246] Step S5.4: Create a model of the drainage ditch behind the wall and calculate the quantities. Through layered modeling and Boolean operations on solids, accurately calculate the quantities of backfill for the opening and the drainage ditch.

[0247] 1) Parameter definition:

[0248] Geometric parameters: Ditch cross-section (e.g., bottom width 0.6m, height 0.4m, wall thickness 0.15m); Layout path: laid out along the outline baseline of the cover layer in step S5-1.

[0249] Engineering parameters: Building materials (C20 concrete, precast U-shaped channel).

[0250] 2) Modeling methods:

[0251] Ditch layout: Input cross-sectional parameters (bottom width, height, wall thickness), and lay out the path along the baseline of the overburden layer; perform a Boolean intersection operation between the laid-out ditch model and the slope surface, and truncate the excess part.

[0252] Model fusion: Chamfer the joints between the ditch and the end wall and the cover layer (chamfer radius ≥ 0.1m).

[0253] 3) Calculation of project quantities:

[0254] Concrete volume: Directly extract the solid volume of the drainage ditch V_drainage ditch;

[0255] Quantity of prefabricated components: calculated based on a single U-shaped channel length of 1.5m: NU-shaped channel = ⌈L drainage ditch / 1.5⌉.

[0256] Step S5.5: Define the path of the intercepting ditch based on the intersection of the slope and the terrain, create the intercepting ditch model, and calculate the quantity of work for the intercepting ditch; based on the intersection of the slope and the terrain, achieve accurate calculation of the quantity of work for the intercepting ditch through parametric lofting and solid modeling.

[0257] 1) Parameter definition:

[0258] Geometric parameters: Interception ditch cross-section: bottom width (0.5~1.0m), height (0.3~0.6m), wall thickness (0.1~0.2m);

[0259] Lofting path: generated along the intersection of the slope and the terrain, with a length that adapts to the terrain range (±50m).

[0260] Engineering parameters:

[0261] Building materials: C20 concrete, precast concrete blocks;

[0262] Interface processing: The chamfer radius of the connecting section is ≥0.1m.

[0263] 2) Modeling methods:

[0264] Drainage ditch path generation: In the BIM platform, the intersection data of the slope and the terrain is called, and the user manually selects the starting point and the ending point; the path is vertically projected onto the terrain surface to generate a three-dimensional spatial curve (projection error ≤ 0.05m).

[0265] Solid lofting modeling: Input the cross-sectional parameters of the intercepting ditch (bottom width, height, wall thickness), perform sweep lofting along the projection path to generate a three-dimensional solid model of the intercepting ditch; perform Boolean intersection operation at the junction of the intercepting ditch with the slope and the back slope to cut off the part that exceeds the terrain range.

[0266] 3) Calculation of project quantities:

[0267] Concrete volume: Directly extract the volume V of the intercepting ditch solid model (accuracy ±0.01m³).

[0268] Quantity of precast blocks: calculated based on a single block length of 1.0m: N blocks = ⌈L intercepting ditch / 1.0⌉.

[0269] Material usage:

[0270] Total weight of concrete: Wconcrete = Vinterceptor ditch 2400 kg / m³;

[0271] Total weight of blocks: W_block = N_block ⋅ 150kg / block.

[0272] Step S6: Summarize the quantities obtained from steps S3 to S6, combine them with the quantity sample table provided by the user, and output the final quantity table for the openings and portals; then generate three views by sectioning, add markings, and output the drawings.

[0273] 1) Data association and mapping: Extract the engineering quantity data (concrete volume, steel reinforcement quantity, earthwork volume, etc.) of each model component, and automatically match it with the engineering quantity sample table fields provided by the user through hash ID (such as "end wall C30 concrete" "HRB400 steel reinforcement"); unmatched fields trigger the manual annotation interface, which supports users to supplement the definition (such as adding the "precast block of intercepting ditch" item).

[0274] 2) Table generation rules: Statistics are categorized and compiled according to the format of the "Standard List of Quantities for Highway Engineering Projects," including:

[0275] Portal structure (end wall, bamboo-cut entrance, bias retaining wall);

[0276] Protective works (slope / upper slope shotcrete, anchor bolts);

[0277] Drainage system (drainage ditch behind the wall, intercepting ditch); earthwork (excavation volume, backfill volume).

[0278] 3) Output fields include: project number, part name, unit, design quantity (3D method), comparison quantity (section method), and deviation rate (step S8 only).

[0279] 4) Dynamic update mechanism: When the model parameters change, the associated engineering quantity data is automatically refreshed through event-driven updates, and the table version number is incremented (e.g., V1.0 → V1.1).

[0280] Example 2

[0281] This invention provides a three-dimensional digital design system for tunnel portals, the system comprising the following steps:

[0282] Based on the tunnel design data, the selected portal location is determined, and a three-dimensional ground model of the portal is constructed.

[0283] The form of the tunnel entrance is determined based on its location and the three-dimensional ground model; the tunnel entrance forms include end-wall type, bias-pressure type, and bamboo-cut type.

[0284] The system automatically designs the corresponding parameters based on external instructions and the type of tunnel portal to form an initial design scheme. In the initial design scheme, each type of tunnel portal includes the following general parameters: location, side slope, open-cut lining, open-cut backfill, and intercepting ditch.

[0285] For end-wall type portals, the system automatically designs the wall structure parameters; for bias-pressure type portals, the system automatically designs the wall structure and bias-pressure retaining wall structure parameters; for bamboo-cut type portals, the system automatically designs the portal structure parameters.

[0286] Adjust the specified parameters in the initial design according to external instructions.

[0287] This invention integrates 3D modeling and automated parametric design into the same system, enabling rapid identification of different types of openings and allowing the processor to execute a series of automatic calculation steps, greatly improving design efficiency and accuracy.

[0288] Example 3

[0289] This invention provides a computer-readable storage medium storing computer-executable instructions thereon, which, when executed by a processor, cause the processor to perform the following steps:

[0290] Based on the tunnel design data, the selected portal location is determined, and a three-dimensional ground model of the portal is constructed.

[0291] The form of the tunnel entrance is determined based on its location and the three-dimensional ground model; the tunnel entrance forms include end-wall type, bias-pressure type, and bamboo-cut type.

[0292] The system automatically designs the corresponding parameters based on external instructions and the type of tunnel portal to form an initial design scheme. In the initial design scheme, each type of tunnel portal includes the following general parameters: location, side slope, open-cut lining, open-cut backfill, and intercepting ditch.

[0293] For end-wall type portals, the system automatically designs the wall structure parameters; for bias-pressure type portals, the system automatically designs the wall structure and bias-pressure retaining wall structure parameters; for bamboo-cut type portals, the system automatically designs the portal structure parameters.

[0294] Adjust the specified parameters in the initial design according to external instructions.

[0295] This invention, by embedding the instructions for implementing the method of this invention on a computer-readable storage medium, can be deployed and executed on various hardware platforms, facilitating cross-system integration and application of three-dimensional digital design of tunnel portals.

[0296] The contents not described in detail in this specification are existing technologies known to those skilled in the art.

Claims

1. A three-dimensional digital design method for tunnel portals in smart highways, characterized in that, Includes the following steps: Based on the tunnel design data, the selected portal location is determined, and a three-dimensional ground model of the portal is constructed. The form of the tunnel entrance is determined based on its location and the three-dimensional ground model; the tunnel entrance forms include end-wall type, bias-pressure type, and bamboo-cut type. The system automatically designs the corresponding parameters based on external instructions and the type of tunnel portal to form an initial design scheme. In the initial design scheme, each type of tunnel portal includes the following general parameters: location, side slope, open-cut lining, open-cut backfill, and intercepting ditch. For end-wall type portals, the wall structure parameters are also automatically designed; For biased portals, the system automatically designs the wall structure and biased retaining wall structure parameters; For bamboo-cut type cave entrances, the system automatically designs the cave entrance construction parameters; Adjust the parameters specified in the initial design scheme according to external instructions; Adjust the parameters specified in the initial design scheme according to external instructions; A 3D model of the opening is constructed based on the revised design scheme, and the engineering quantity and drawings are calculated based on the BIM 3D model. The automatic design process for the parameters of the slope includes: Using the excavation location as the benchmark point for slope calculation, and based on the preset slope ratio and grade height, the slope line is extended outward along the three-dimensional terrain station by station, and the intersection point of the slope line and the terrain is calculated. When the calculated height corresponding to any intersection point reaches the graded height, a platform is set at or near the intersection point, and the platform position is used as the new slope calculation benchmark point to repeat the above slope line calculation and judgment process until a complete slope model is formed on the left, right and up slope directions. Boolean operations were performed on the left slope model, right slope model, and uphill slope model to trim overlapping and redundant parts to form a closed area as the excavation model for the tunnel entrance. The area below the backfill position in the excavation model is defined as the temporary support range, and the area above the backfill position is defined as the permanent support range. The corresponding support area is calculated based on the excavation model.

2. The method according to claim 1, characterized in that: The design order of the above parameters, from first to last, is: location, lining of the open passage, wall structure or opening structure, side slope, backfilling of the open passage, and intercepting ditch. The eccentric retaining wall structure is designed simultaneously with the wall structure.

3. The method according to claim 1, characterized in that: The process of determining the form of the tunnel entrance based on its location and the three-dimensional ground model includes: At the bottom elevation point of the tunnel lining, after offsetting to the left and right sides by the reserved width, the starting points on the left and right sides are determined. Calculate the elevation difference between the starting point and the intersection point with the ground; Obtain the inner contour height of the tunnel; The portal type is determined based on the comparison between the elevation difference and the inner contour height. When the calculation of the elevation difference between the left and right sides is invalid, or when the elevation difference between the left and right sides is less than or equal to the inner contour height, it is determined to be a bamboo-cutting type doorway. When the elevation difference on only one side is less than or equal to the height of the inner contour, it is determined to be an eccentric portal. When the elevation difference between the left and right sides is greater than the height of the inner contour, it is determined to be an end-wall type portal.

4. The method according to claim 1, characterized in that: The process of calculating the quantity of engineering work based on a BIM 3D model includes: Extract the volume of walls and retaining walls from the BIM 3D model to calculate the concrete volume, and extract the length of the steel reinforcement model to calculate the steel reinforcement usage; For slopes and uphill slopes, the surface area is extracted from the BIM 3D model and multiplied by the sprayed concrete design thickness to calculate the volume of sprayed concrete, and the number of anchors is calculated according to the anchor arrangement rules. Based on the set soil layer thickness, an earthwork entity and a rockwork entity are generated below the terrain model in the BIM 3D model. The excavation space enclosed by the end wall, retaining wall, slope, and back slope models are compared with the earthwork entity and the rockwork entity to obtain the actual excavation entity. The resulting earthwork volume and rockwork volume are calculated cumulatively. Create a backfill model for the opening and a drainage ditch model behind the wall, and extract the backfill volume and drainage ditch volume from the BIM 3D model based on the model; The above calculation results are automatically linked to the bill of quantities field, and the quantities of portal structures, slope protection works, drainage works and earthwork are generated in the prescribed format. When the parameters of the BIM 3D model change, the update is automatically triggered to refresh the relevant quantity data.

5. The method according to claim 1, characterized in that: The automatic design process for the parameters of the tunnel lining includes: The steps for automatically calculating and determining the recommended length of the tunnel lining include: The initial value of the lining length of the open-cut tunnel is set to zero; Based on topographic data, engineering design specifications, and the current length of the tunnel lining, the location of the slope initiation point is determined, and then the elevation of the slope initiation point is calculated. If the elevation of the starting point is less than the elevation of the top of the tunnel lining, the length of the tunnel lining is increased by a preset step size and the elevation of the starting point of the uphill slope is recalculated. When the elevation of the starting point is greater than or equal to the elevation of the top of the tunnel lining, the trial calculation is terminated and the length of the tunnel lining at this time is determined as the recommended value. After obtaining the recommended value, the actual lining thickness specified by the user is received, and the lining of the open tunnel is stretched and laid out along the direction perpendicular to the reference plane using the set standard cross-section as the reference plane to generate a three-dimensional open tunnel lining model.

6. The method according to claim 1, characterized in that: The backfill parameters for the open channel are designed sequentially from bottom to top: The height of the left and right sides of the bottom backfill and the bottom backfill material are determined according to external instructions; The backfill material for the middle section will be determined based on external instructions. In top backfill design, the backfill profile is automatically calculated and adjusted through the following steps: The shape of the top backfill is defined by the width of the left and right sides of the tunnel wall, and the intersection of the top backfill layer and the side slope is calculated to form the initial backfill shape. Provides the ability to add line segment vertices, allowing the initial backfill shape line segment to be broken at any position where adjustment is needed; Whenever a line segment vertex is added, the connection relationship and direction of the backfill shape are updated in real time, and the backfill contour is refined to ultimately form a top backfill shape that meets the requirements of mountain stability and drainage.

7. The method according to claim 1, characterized in that: The automatic design process for the intercepting ditch parameters includes: Obtain the intersection data of the slope model and the terrain, and generate a three-dimensional polyline representing the initial layout line of the intercepting ditch; The three-dimensional polyline is projected onto a horizontal plane to obtain a projection line; According to the preset offset rules, the projection line is offset away from the opening to obtain the offset line; The offset line is then projected onto the three-dimensional terrain to generate the preliminary layout line of the intercepting ditch. The intercepting ditch layout line is updated according to external instructions, and a solid model of the intercepting ditch is generated based on the selected cross-sectional shape of the intercepting ditch.

8. The method according to claim 1, characterized in that: The automatic design process for the wall structure parameters includes: The sum of the tunnel cross-sectional shape and height, the thickness of the open-cut lining, the lining depth, and the reserved height is taken as the initial height of the end wall; Based on the tunnel width and road width information, the coordinates of the excavation positions on both sides are determined, and combined with the preset slope ratio, the intersection points of the left and right slopes and the road surface are calculated, thereby obtaining the actual width of the end wall. Based on the top elevation of the wall, topographic undulations, and slopes of both sides, the width and height range of a single top step are defined; using 3D modeling technology, the intersection position between the top backfill and the end wall is calculated; based on the intersection position and the overall stability requirements of the end wall, the number of top steps and the start and end coordinates of each step are determined. Based on the measurement data of the intersection of the wall and the terrain and the requirements of engineering mechanics, the range of values ​​for the width and height of a single bottom step is defined, and the number of bottom steps and the arrangement of each step are calculated according to the length and height difference of the intersection of the wall and the terrain on both sides.

9. The method according to claim 1, characterized in that: The automatic design process for the biased retaining wall parameters includes: Choose the location of the retaining wall on the plane; Based on the intersection of the ground line and the top of the retaining wall, determine whether the retaining wall should be separated from the lining of the open tunnel, and calculate the recommended value for the separation width; Calculate the intersection point between the retaining wall and the terrain on the side furthest from the end wall, and determine the length of the retaining wall through this intersection point.

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