Pile length simulation and prediction method based on pile foundation and iterative geological BIM model

Abstract

The invention discloses a method for simulating the pile length based on a BIM model of a pile foundation and a terrain, belongs to the technical field of construction engineering construction, and particularly designs a method for predicting the pile length based on a BIM pile foundation model and a geologic model. According to the method, Revit and a visual programming tool dynamo of the Revit are used for conducting rapid parameterization on a pile foundation and a stratum of a project to generate a civil engineering model, and parameterization control is established; the control content comprises the steps of adding stratum data point parameterization to update the stratum, and controlling the pile length of a specified pile through the pile number. The intersection point of the pile and the stratum is calculated in a parameterization mode in the model, the intersection point is converted into the predicted pile length, and expected numerical values of the using amount of reinforcing steel bars and concrete of the pile and the pore-forming time length are achieved before construction is started. Along with continuous construction of the pile, actual pile length in-rock data of construction is interpolated into an original stratum data set, then a geologic model is iterated, the simulated pile length is updated, the prediction precision of the pile length is improved, lean management of the pile main material consumption and the construction progress in the construction process is achieved, and the purposes of cost prediction and control and reasonable resource allocation through the BIM technology are achieved.

Description

Technical Field

[0001] The present invention performs pile length simulation based on a BIM model of a pile foundation and terrain during a construction process, and belongs to the technical field of construction engineering. Background Art

[0002] As the load-bearing component of the entire building structure, the quality of pile foundation construction directly determines the building's functionality. Pile length control is a key element in pile foundation quality acceptance. If the pile length does not meet acceptance requirements, the pile is deemed invalid. Pile length estimation before and during construction is crucial for project quality control. Efficient and accurate pile length estimation improves project quality control and structural safety, avoiding unnecessary construction delays and increased costs caused by inadequate pile length control.

[0003] Currently, pile length estimation prior to pile foundation construction is primarily based on geological survey data, the designed pile length provided by the design institute, and the team's experience after on-site investigations. Relying solely on this preliminary survey data can lead to insufficient or inaccurate geological conditions, potentially affecting pile length design and construction control.

[0004] The construction depth of pile foundations (end-bearing piles) is typically determined by reaching a certain stratum as the final hole control condition. Stratum boundaries, as the boundaries between different strata, are typically composed of different types of rock or sediment, which accumulate or deposit in a continuous pattern underground. This continuity results in stratum boundaries typically presenting relatively smooth curved surfaces. However, their formation process may be affected by certain disturbances, resulting in some local irregularities and random fluctuations in the interface. Therefore, stratum boundaries can generally be considered approximately curved surfaces, although they may not be completely smooth.

[0005] Currently, the digital application of BIM technology is being widely promoted in the engineering construction field. Based on the characteristics of the ground interface, the triangulation approximation method integrated into BIM modeling software can be used to fit the approximate surface shape of the ground interface and calculate the estimated pile length, providing relatively reliable estimated pile length data for construction operations. Summary of the Invention

[0006] To address the aforementioned problem of determining estimated pile length during construction, the present invention provides a pile length simulation and prediction method based on a pile foundation and geological BIM model. This method converts newly added pile data into stratum interface data and interpolates the original geological exploration data to achieve iterative simulation of the stratum interface, providing relatively reliable estimated pile length data for pile foundation construction. This achieves the goal of using BIM technology for cost forecasting and control, and rationally allocating resources.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is:

[0008] Pile length simulation based on the BIM model of the pile foundation and geology is characterized by the following steps:

[0009] Step 1: Use Dynamo to automatically place and number the pile foundation components and quickly create a pile foundation BIM model

[0010] Dynamo is used to identify the pile foundation CAD drawings. By identifying the pile number, pile location and other information, the pile components are placed at one time. Then the pile number parameters are assigned and the height position parameters (elevation and pile top offset parameters) are modified. Two duplicate piles are placed at each pile site in the pile foundation BIM model, which are used to represent the actual length of the pile section reaching the rock surface (referred to as the actual pile section length). ) and simulated pile segment length , the two sets of piles are represented by different colors using Revit filters and parameter "annotation" as judgment conditions;

[0011] Step 2: Use existing geological exploration data to obtain a set of three-dimensional spatial coordinate points of the stratum interface , each coordinate point is , in order to create the geological BIM model, the coordinate system used for the geological space coordinate points is consistent with that in the pile foundation BIM model. The geological BIM surface model is the deepest stratum interface to be reached when the pile is constructed at the end of the hole;

[0012] Step 3: Perform visual programming in Dynamo to modify and control the pile length, specifically:

[0013] (1) Extract the pile family, obtain all pile instances in the model, and get the pile number Parameter list, each pile is precisely controlled by the pile number. Extract the "center coordinates { }" and other parameters;

[0014] (2) Triangulate the terrain surface obtained in step 2 to obtain the set of all triangular faces , the triangulation process conforms to the characteristics of Delaunay triangulation;

[0015] (3) Draw a line segment along the Z direction from the center point of the pile position and intersect it with the triangular surface of the stratum to obtain the simulated pile length. The vertical downward structural long line segment intersects with the triangular surface of the stratum, and the filtered and screened Each corresponding , calculate the length of the segment intercepted by the triangle , which is used as the value of the simulated pile segment length. When this step is performed for the first time, all pile lengths are the simulated pile segment lengths, that is, , the two sets of piles completely overlap, and the entire model is initialized;

[0016] (4) Interpolation points are used to regenerate the geological surface. Collect the engineering pile data completed every day or at specific time intervals as the source of interpolation points. Organize the engineering pile data table to obtain the pile numbers that need to be imported into the calculation script. , iterative data of actual pile segments and newly added geological coordinate data ,here:

[0017] = Effective pile length (L) - rock embedment depth ( ), The actual pile length indicating that the depth reached is the geological interface;

[0018] = Pile bottom elevation (H) + rock embedded depth ( ), Indicates the ground interface elevation under the actual pile location.

[0019] Import the data into Dynamo and change the pile center point under the corresponding pile number of Replace the value with , the newly added geological surface spatial coordinate points are ; Merge the newly added geological coordinates into the initial data to obtain a new set of three-dimensional spatial coordinate points on the stratigraphic boundary surface , realize the regeneration of the stratum interface model;

[0020] (5) Each time the actual data is imported, the actual pile segment length under the corresponding pile number in the model is replaced, and the simulated pile segment length remains unchanged, that is, , At this time, after the filter sets different colors, the two piles superimposed at the same position will appear in different colors in the BIM model. The pile length under this pile number remains unchanged in subsequent iterative calculations. The remaining pile numbers that have not been replaced by actual data will be re-simulated with a new pile length due to the change of the stratum interface model. , , Indicates the number of times the pile length is imported, i.e. the new pile length is iterated as the simulated pile length changes with the stratum model. Repeat steps 4 and 5 for each import.

[0021] (6) Data export. Each time data is imported for iterative calculation, , pile number as well as The export will be used to analyze the effects and errors of pile length simulation.

[0022] The pile foundation BIM model is constructed by overlaying two sets of pile models, both controlled by a Dynamo script. Each pile is assigned a specific annotation and number, which serves as a distinguishing factor and a filter. Two pile models are superimposed at the same location, representing the simulated and actual piles, respectively, with distinct annotations assigned. A filter is used to assign different colors to the model's appearance. When the pile models overlap, the same overlay color appears. When the simulated and actual lengths differ, a color difference segment appears. The length of the color difference segment directly reflects the difference between the simulated and actual lengths in the model.

[0023] The calculation of the simulated pile segment length in this method essentially involves calculating the vertical distance from a 3D point to a surface along the z-axis. The center coordinate point of the pile top is extracted in Dynamo. A long line segment is drawn vertically downward through this point. This line segment will inevitably intersect with a triangular surface, forming an intersection point. This intersection point is the vertical projection point of the 3D point on the determined surface. The difference in the z-values ​​of the two points is the simulated pile length.

[0024] This method improves the accuracy of geological simulations by interpolating additional points, and controls the order of interpolation to increase the efficiency of stratigraphic simulation accuracy. The source of these additional points is not new geological exploration data, but rather the rock-embedded data of newly constructed piles converted into geological data, thereby converting a sparse point set into a dense one.

[0025] All simulation operations, except for the data analysis of the results, are performed in Revit and the Dynamo plug-in, eliminating the need for model or data transfer between different software programs. Two Dynamo script files, "Automatic Pile Foundation CAD Drawing Modeling" and "Geological Pile Length Simulation," were independently compiled. When programming in the Dynamo operating space, node functions are grouped and labeled, and the transfer of list data between important nodes is standardized. Sliding input modules are provided at the input and output terminals, and the Dynamo script files are imported into the Dynamo player, which then performs simulation operations in a small window player format. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Schematic diagram of the process of the present invention.

[0027] Figure 2 Two sets of piles at the same location are colored to indicate different pile lengths.

[0028] Figure 3 It is a schematic flow chart of the pile length calculation method of the present invention.

[0029] Figure 4 The pile foundation design drawings and design data in the example of the present invention;

[0030] Figure 5 is the simulated pile segment length result after iterative calculation in the example of the present invention;

[0031] Figure 6 A statistical table of actual pile lengths in the examples of the present invention;

[0032] Figure 7 This is a comparison diagram of the interpolated iterative stratum and the estimated pile length in the example of the present invention. DETAILED DESCRIPTION

[0033] In order to facilitate those skilled in the art to understand and implement the present invention, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the implementation examples described herein are only used to illustrate and explain the present invention.

[0034] Pile foundation simulation based on the geological BIM model includes the following steps:

[0035] Step 1: Based on the project’s CAD foundation plan, use Dynamo to automatically place and number the pile foundations, create a BIM model of the pile foundations, and copy another set of piles in the same location, giving them different annotations.

[0036] Step 2: Collect the geological exploration data of the project, obtain the three-dimensional spatial coordinate point set of the stratum interface, and create a BIM model of the geological boundary surface.

[0037] Step 3: Combine the pile foundation BIM model with the stratum interface BIM model, and the coordinate system used for the geological space coordinate points should be consistent with that in the pile foundation BIM model.

[0038] Step 4: Arrange the engineering pile data table, obtain the pile number and iterative data of the actual pile segment that need to be imported into the calculation script, create an "input pile length data table", group the data and set an empty table as the initialization condition to prepare for the import.

[0039] Step 5: Create two tables in Excel: "Geological Iteration Data" and "Pile Length Iteration Data".

[0040] Step 6: Open the Dynamo player, import the Dynamo script file, click Edit Input, select the Excel files required by the content on the interface (geological exploration data table, input pile length data table, geological iteration data table, pile length iteration data table), and select the corresponding worksheet number in each Excel file by sliding input to complete the editing.

[0041] Step 7: Enter the pile length data table, select an empty table, and click Run to complete the model initialization.

[0042] Step 8: Change the worksheet number and run it multiple times to obtain a series of pile length iteration data.

[0043] Step 9: Perform mathematical analysis on the exported table of pile length iteration data.

[0044] Step 10: Give a predicted value for the pile length and formulate a subsequent piling plan.

[0045] Using Z88# pile as the target pile, we conducted iterative calculations and analysis, and compared the results with the actual drilling data:

[0046] Z88# pile initialization,

[0047] Take Z83# pile as the first interpolation point, and its center coordinates as the standard , ,

[0048] After interpolating the newly added geological coordinates, the first iteration calculation is completed and we get

[0049] Take Z87# pile as the second interpolation point,

[0050] The second iterative calculation yields

[0051] According to the actual drilling data of Z88# pile,

[0052] During initialization, the error rate

[0053] The first iteration calculation, error rate

[0054] The second iteration calculation, error rate

[0055] As the number of iterations increases, the error in the simulated length of the target pile gradually decreases. According to the data above, after the second iteration, the simulated length of the Z88# pile differed from the true value by only 0.015m, with an error rate of -0.17%, very close to the actual pile length, demonstrating the effectiveness of the simulation method.

[0056] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the scope of protection of the claims of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. Pile length simulation and prediction method based on pile foundation and iterative geological BIM model, Its characteristics include the following steps: Step 1: Use Dynamo to automatically place and number the pile foundation components and quickly create a pile foundation BIM model Dynamo is used to identify the pile foundation CAD drawings. By identifying the pile number, pile location and other information, the pile components are placed at one time. Then the pile number parameters are assigned and the height position parameters (elevation and pile top offset parameters) are modified. Two duplicate piles are placed at each pile site in the pile foundation BIM model, which are used to represent the actual length of the pile section reaching the rock surface (referred to as the actual pile section length). ) and simulated pile segment length , the two sets of piles are represented by different colors using Revit filters and parameter "annotation" as judgment conditions; Step 2: Use existing geological exploration data to obtain a set of three-dimensional spatial coordinate points of the stratum interface , each coordinate point is , in order to create a geological BIM model; the coordinate system used by the geological space coordinate points is consistent with that in the pile foundation BIM model, and the geological BIM surface model is the deepest stratum interface to be reached when the pile is constructed at the end of the hole; Step 3: Perform visual programming in Dynamo to modify and control the pile length, specifically: (1) Extract the pile family, obtain all pile instances in the model, and get the pile number Parameter list, each pile is precisely controlled by the pile number. Extract the "center coordinates { }" and other parameters; (2) Triangulate the terrain surface obtained in step 2 to obtain the set of all triangular faces , the triangulation process conforms to the characteristics of Delaunay triangulation; (3) Draw a line segment along the Z direction from the center point of the pile position and intersect it with the triangular surface of the stratum to obtain the simulated pile length. The vertical downward structural long line segment intersects with the triangular surface of the stratum, and the filtered and screened Each corresponding , calculate the length of the segment intercepted by the triangle , which is used as the value of the simulated pile segment length. When this step is performed for the first time, all pile lengths are the simulated pile segment lengths, that is, , the two sets of piles completely overlap, and the entire model is initialized; (4) Interpolation points are used to regenerate the geological surface. Collect the engineering pile data completed every day or at specific time intervals as the source of interpolation points. Organize the engineering pile data table to obtain the pile numbers that need to be imported into the calculation script. , iterative data of actual pile segments and newly added geological coordinate data ,here: = Effective pile length (L) - rock embedment depth ( ), The actual pile length indicating that the depth reached is the geological interface; = Pile bottom elevation (H) + rock embedded depth ( ), Indicates the ground interface elevation under the actual pile location. Import the data into Dynamo and change the pile center point under the corresponding pile number of Replace the value with , the newly added geological surface spatial coordinate points are ; Merge the newly added geological coordinates into the initial data to obtain a new set of three-dimensional spatial coordinate points on the stratigraphic boundary surface , realize the regeneration of the stratum interface model; (5) Each time the actual data is imported, the actual pile segment length under the corresponding pile number in the model is replaced, and the simulated pile segment length remains unchanged, that is: , At this time, after the filter sets different colors, the two piles superimposed at the same position will appear in different colors in the BIM model. The pile length under this pile number remains unchanged in subsequent iterative calculations. The remaining pile numbers that have not been replaced by actual data will be re-simulated with a new pile length due to the change of the stratum interface model. , , Indicates the number of times the pile length is imported, i.e. the new pile length is iterated as the simulated pile length changes with the stratum model. Repeat steps 4 and 5 for each import. (6) Data export. Each time data is imported for iterative calculation, , pile number as well as The export will be used to analyze the effects and errors of pile length simulation.

2. As claimed in claim 1, it is characterized in that The pile family was designed parametrically. The pile foundation BIM model consists of two superimposed pile models, both controlled by a Dynamo script. Each pile is assigned a specific annotation and number, which serves as a distinguishing factor and a filter. Two pile models are superimposed at the same location, representing the simulated and actual piles, respectively, with distinct annotations assigned. A filter is used to assign different colors to the model appearance. When the pile models overlap, the same superimposed color appears. When the simulated and actual lengths differ, a color difference segment appears. The length of the color difference segment directly reflects the difference between the simulated and actual lengths in the model.

3. As claimed in claim 1, it is characterized in that Calculation method for simulated pile length. The calculation of the simulated pile segment length in the present invention is essentially to calculate the vertical distance in the z-axis direction from the three-dimensional point to the surface. In Dynamo, the center coordinate point of the pile top is extracted, and a long line segment is drawn vertically downward through this point. The line segment will inevitably intersect with a certain triangular surface to produce an intersection point. This intersection point is the vertical projection point of the three-dimensional point on the determined surface. The difference in the z values ​​of the two points is the value of the simulated pile length.

4. As claimed in claim 1, it is characterized in that Interpolation improves the accuracy of geological simulations, and controlling the order of interpolation increases the efficiency of stratigraphic simulation accuracy. The source of these additional points is not new geological exploration data, but rather the rock-embedded data of newly constructed piles converted into geological data, thereby converting a sparse point set into a dense one.

5. As claimed in claim 1, it is characterized in that All simulation operations, except for data analysis of the results, are performed within Revit and the Dynamo plug-in, eliminating the need for model or data transfer between different software programs. Two Dynamo scripts, "Automatic Pile Foundation CAD Drawing Modeling" and "Geological Pile Length Simulation," were independently developed. When programming within the Dynamo operating space, node functions are grouped and labeled, and the transfer of tabular data between important nodes is standardized. Sliding input modules are provided at the input and output terminals, and the Dynamo script files are imported into the Dynamo player, where simulation operations are performed in a small window.

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