Construction progress monitoring method and system based on combination of oblique photography and BIM, and medium

Abstract

The present application relates to a construction progress monitoring method and system based on oblique photography combined with BIM, and a medium, the method comprising: constructing a three-dimensional real scene model using an unmanned aerial vehicle oblique photography technology; constructing a BIM three-dimensional model and a BIM four-dimensional model using a BIM technology; matching the three-dimensional real scene model with the BIM three-dimensional model through a Boolean algorithm, on the basis of the matching, using the three-dimensional real scene model to subdivide the BIM three-dimensional model, and calculating and analyzing the subdivision result to obtain a construction progress report; and participating the construction progress report in the BIM four-dimensional model to realize construction progress monitoring. The present application can enable relevant personnel to intuitively and visually understand progress deviation in the process of construction progress monitoring, and realize automatic and intelligent monitoring management of construction progress; not only can solve the problem that a BIM three-dimensional model is easy to deviate from the actual situation on site, but also can avoid subjective errors caused by manually matching a three-dimensional real scene model with a BIM three-dimensional model.

Description

Technical Field

[0001] This invention relates to the field of construction progress monitoring, specifically to a construction progress monitoring method, system, and medium based on the combination of oblique photography and BIM. Background Technology

[0002] Construction progress is a crucial factor in evaluating project quality and cost. Due to the complexity and variability of construction sites, and the time-consuming and labor-intensive nature of traditional manual progress monitoring, project progress control is quite challenging.

[0003] Specifically, real-time monitoring of highway projects under construction to ensure their smooth progress is of great significance to national traffic management and economic strategic planning. However, due to the long routes and long cycles of highway projects, relying solely on manual methods for construction progress monitoring is prone to subjective experience errors, is time-consuming, labor-intensive, and has significant limitations. To address this, many scholars have conducted research on construction progress monitoring methods and achieved some results. For example, BIM technology can be used to simulate the entire construction process and monitor progress in real time. However, BIM models are static and detached from actual site conditions, making real-time and accurate progress monitoring impossible. Another example is the semi-automatic verification of the construction progress of interior doors and windows by manually selecting matching points between the BIM model and the 3D point cloud, but this is subject to subjective errors caused by manually matching two data models. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a construction progress monitoring method, system and medium based on oblique photography and BIM. It can not only solve the problem that relying solely on BIM 3D models is prone to deviating from the actual situation on site, but also avoid the subjective errors caused by manually matching 3D real scene models and BIM 3D models, and can effectively improve the accuracy and automation of construction progress monitoring.

[0005] The technical solution of this invention to solve the above-mentioned technical problems is as follows: a construction progress monitoring method based on oblique photogrammetry and BIM, comprising the following steps:

[0006] S1. Use UAV oblique photography technology to obtain aerial survey data of the construction site, and construct a three-dimensional real scene model based on the aerial survey data;

[0007] S2, use BIM technology to model the construction site to obtain a BIM three-dimensional model, and assign time attributes to the BIM three-dimensional model to obtain a BIM four-dimensional model;

[0008] S3. The three-dimensional real-scene model is matched with the BIM three-dimensional model using a Boolean algorithm. Based on the matching, the three-dimensional real-scene model is used to segment the BIM three-dimensional model, and the segmentation results are calculated and analyzed to obtain a construction progress report. The construction progress report is then incorporated into the BIM four-dimensional model to achieve construction progress monitoring.

[0009] Based on the above-mentioned construction progress monitoring method based on the combination of oblique photogrammetry and BIM, the present invention also provides a construction progress monitoring system based on the combination of oblique photogrammetry and BIM.

[0010] A construction progress monitoring system based on oblique photogrammetry and BIM includes the following modules:

[0011] A 3D reality model building module is used to acquire aerial survey data of the construction site using UAV oblique photography technology, and to build a 3D reality model based on the aerial survey data.

[0012] The BIM model building module is used to model the construction site using BIM technology to obtain a BIM three-dimensional model, and to assign time attributes to the BIM three-dimensional model to obtain a BIM four-dimensional model.

[0013] The progress analysis module is used to match the 3D reality model with the BIM 3D model using a Boolean algorithm. Based on the matching, the 3D reality model is used to segment the BIM 3D model, and the segmentation results are calculated and analyzed to obtain a construction progress report. The construction progress report is then incorporated into the BIM 4D model to achieve construction progress monitoring.

[0014] Based on the above-mentioned construction progress monitoring method combining oblique photography and BIM, the present invention also provides a computer-readable storage medium.

[0015] A computer-readable storage medium storing a computer program that, when executed by a processor, implements the aforementioned construction progress monitoring method based on oblique photography and BIM integration.

[0016] The beneficial effects of this invention are as follows: In the construction progress monitoring method, system, and medium based on the combination of oblique photogrammetry and BIM, a three-dimensional real-scene model is first constructed using UAV oblique photogrammetry technology. Then, a detailed and visualized BIM three-dimensional model and a BIM four-dimensional model with time attributes are constructed using BIM technology. Finally, the three-dimensional real-scene model and the BIM three-dimensional model are combined, allowing the BIM three-dimensional model to be well connected with the construction site. The three-dimensional real-scene model and the BIM three-dimensional model can be accurately matched, segmented, calculated, and analyzed to generate a clear and concise project progress report to obtain the actual construction progress of the highway. Furthermore, by combining it with the construction progress of the BIM four-dimensional model, the construction progress of the highway can be monitored, and relevant personnel can more intuitively and visually reflect progress deviations through report information, providing solutions to the construction site and achieving automated and intelligent monitoring and management of construction progress. The method and system of this invention not only solve the problem that relying solely on the BIM three-dimensional model is prone to deviating from the actual site conditions, but also avoids subjective errors caused by manually matching the three-dimensional real-scene model and the BIM three-dimensional model, effectively improving the accuracy and automation of construction progress monitoring. Attached Figure Description

[0017] Figure 1 This is a flowchart of the construction progress monitoring method based on the combination of oblique photography and BIM according to the present invention;

[0018] Figure 2 This is a schematic diagram of the construction progress monitoring method based on the combination of oblique photography and BIM of the present invention.

[0019] Figure 3 A flowchart illustrating the BIM 3D information model construction process based on the Benltey platform software;

[0020] Figure 4 A flowchart for creating a BIM 4D model;

[0021] Figure 5 This is a diagram of the Reality Model Progress Analysis section in the Reality Model Progress Analysis plugin;

[0022] Figure 6 This is a three-dimensional real-scene model of the first phase of the construction section of the Pingnan Expressway from chainage K114+600 to K116+200 in an example of the present invention.

[0023] Figure 7 This is a black-and-white grid 3D real-scene model of the first phase of the construction section of the Pingnan Expressway from chainage K114+600 to K116+200 in an example of the present invention;

[0024] Figure 8This is a partial view of the BIM 3D model of the construction section of the Pingnan Expressway from chainage K114+600 to K116+200 in an example of the present invention;

[0025] Figure 9 This is a partial view of the fusion of the three-dimensional reality model and the BIM three-dimensional model of the first phase of the construction section of the Pingnan Expressway from chainage K114+600 to K116+200 in an example of the present invention;

[0026] Figure 10 This is a 3D reality model of the second phase of the construction section of the Pingnan Expressway from chainage K114+600 to K116+200 in an example of the present invention.

[0027] Figure 11 This is a three-dimensional real-scene model of the second phase of the construction section of the Pingnan Expressway from chainage K114+600 to K116+200 in this invention example;

[0028] Figure 12 This is a structural block diagram of the construction progress monitoring system based on oblique photography and BIM, which is based on the present invention. Detailed Implementation

[0029] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0030] like Figure 1 As shown, the construction progress monitoring method based on oblique photography combined with BIM includes the following steps:

[0031] S1. Use UAV oblique photography technology to obtain aerial survey data of the construction site, and construct a three-dimensional real scene model based on the aerial survey data;

[0032] S2, use BIM technology to model the construction site to obtain a BIM three-dimensional model, and assign time attributes to the BIM three-dimensional model to obtain a BIM four-dimensional model;

[0033] S3. The three-dimensional real-scene model is matched with the BIM three-dimensional model using a Boolean algorithm. Based on the matching, the three-dimensional real-scene model is used to segment the BIM three-dimensional model, and the segmentation results are calculated and analyzed to obtain a construction progress report. The construction progress report is then incorporated into the BIM four-dimensional model to achieve construction progress monitoring.

[0034] The method of this invention includes three core steps: three-dimensional reality model construction, BIM model construction, and progress analysis, such as... Figure 2 As shown, specifically, S1 corresponds to the construction of a 3D reality model, S2 corresponds to the construction of a BIM model, and S3 corresponds to progress analysis.

[0035] The following sections provide a detailed explanation of each step.

[0036] 3D Reality Model Construction:

[0037] Unmanned aerial vehicle (UAV) oblique photogrammetry is an emerging technological method that uses five sensors mounted on a single flight platform to simultaneously capture images from five different angles—one vertical and four oblique—overcoming the limitation of traditional orthophotos, which can only analyze ground features vertically. These lenses enable the rapid acquisition of high-resolution texture information of ground features from all directions, achieving large-scale, high-volume, and efficient geospatial data collection. This provides cost-effective, efficient, and agile data support and services for industries such as public security, planning, emergency response, and surveying, and enhances the ability to flexibly and quickly acquire detailed 3D model data.

[0038] Specifically, S1 is,

[0039] S11, Conduct on-site surveys and set up image control points at the construction site;

[0040] S12, Based on the survey of the construction site, a flight path is designed so that the drone equipped with five cameras flies along the designed flight path and uses the five cameras to simultaneously take pictures at the construction site from one vertical angle and four different tilt angles to obtain aerial survey data.

[0041] S13, the aerial survey data is sequentially imported, aerial triangulated, and reconstructed in three dimensions to obtain an initial three-dimensional real-world model;

[0042] S14, perform accuracy detection on the initial 3D real scene model to determine whether the accuracy of the initial 3D real scene model meets the preset model accuracy; if not, return to S11 and repeat; if yes, use the initial 3D real scene model as the final 3D real scene model.

[0043] The reconstruction of a 3D reality model of the construction site is a fundamental step in the method proposed in this invention, and the acquired 3D reality model serves as the basic data for monitoring construction progress. This invention's 3D reality model construction based on UAV oblique photogrammetry technology mainly consists of two parts: field aerial survey data acquisition and indoor data processing. In the field aerial survey data acquisition, flight routes are rationally planned based on the terrain, scope, and UAV endurance of the project area. The image control points deployed at the project site are used to match the model with the actual geodetic coordinates, controlling the model error to within centimeters. The flight route design includes aerial survey altitude, aerial survey overlap, and aerial survey range. The aerial survey altitude is designed based on the height of surrounding buildings and mountains. The aerial survey overlap is specified to be 85% for both forward and lateral overlap. The aerial survey range extends beyond the boundary of the survey area by at least three baselines. In the indoor data processing, it mainly consists of three parts: data import, aerial triangulation, and 3D reconstruction. Data import primarily processes the aerial survey data acquired by the UAV, including image data, POS coordinates, and image control point data, ensuring data integrity and correct format. In the feature point matching process of 3D reconstruction, bundle adjustment is used to eliminate matching errors, making the matching more accurate.

[0044] Bundle adjustment primarily uses the camera's attitude and the three-dimensional coordinates of the measurement points as unknown parameters, and uses the coordinates of feature points detected on the image for forward intersection as observation data to perform adjustment and obtain the optimal camera parameters and world point coordinates.

[0045] Given the coordinates of the two-dimensional image point L imgage = (x, y), the corresponding three-dimensional world point coordinates are P. world = (x, y, z) can be obtained from the collinearity equation in photogrammetry, and the ideal state of the collinearity equation is L. imgage =PX world This equation establishes a functional model between the observed data and the parameters to be determined. It belongs to the Gauss-Markov model in adjustment, which can be understood as transforming the real coordinates of the three-dimensional world into coordinates on a two-dimensional image through the camera's built-in matrix. However, the projection equation of each image point in each image can contribute two equations. Typically, hundreds of matching points can be obtained on average per image, resulting in a larger number of equations than the parameters to be determined. In this case, due to observation noise, a strictly unique solution cannot be obtained, i.e., the ideal state L... imgage =PX world Therefore, a correction factor is needed to make this equation hold, namely L. imgage =Q+PX worldThe error originates from the observed values ​​and is generally assumed to be a random error following a Gaussian distribution. This equation can always be made true by adding certain corrections, thus there are infinitely many corrections. However, if we impose a constraint on the number of corrections: the sum of the squares of the corrections must be minimized, i.e., Q must be minimized... T If we calculate Q, we can hope to obtain a unique solution. The result obtained under this constraint is the optimal estimate, i.e., the adjustment solution.

[0046] BIM model construction:

[0047] BIM technology is a model that integrates various data and information of an engineering project, based on three-dimensional digital technology. By assigning a time attribute to the BIM three-dimensional model, a BIM four-dimensional model (4D model) can be constructed, which visually represents the construction simulation process and related data, thus breaking away from the traditional methods of expression using charts and text descriptions—this is BIM-4D technology. Based on this technology, engineering design, construction, and optimization can be completed quickly and efficiently, playing a significant role in calculating quantities, implementing construction monitoring, overcoming construction difficulties, and improving construction quality. Applying BIM-4D technology to the management of engineering construction progress helps improve project management efficiency and level, providing strong technical support for the automated monitoring of project progress. However, the construction phase is a complex and dynamic process characterized by long cycles, large scale, and complex processes; relying solely on the BIM three-dimensional model can easily deviate from the actual site conditions.

[0048] Therefore, based on the characteristics of highway design and construction, and combining the advantages of UAV oblique photography technology and BIM technology, this invention proposes a method for monitoring project progress by combining UAV oblique photography technology and BIM technology.

[0049] BIM technology permeates the entire lifecycle of engineering project systems, and the construction of BIM 3D models is a prerequisite for project managers to effectively monitor the progress of highway engineering projects using BIM technology. In BIM applications for road and bridge projects, the mainstream BIM design platform software currently available is Autodesk, Bentley, and Dassult. Among them, Bentley platform software not only has powerful interactive functions but also good lightweight processing capabilities. The software format is unified with DNG format and can be further processed and edited through reference, greatly reducing the computer load and improving modeling efficiency. Therefore, Bentley platform software was used for the construction of the BIM 3D model in this project.

[0050] In this specific embodiment, the construction progress monitoring method is specifically used to monitor the progress of a highway engineering project; S2 specifically refers to...

[0051] S21. Based on the Bentley platform software, road visualization modeling and bridge visualization modeling are performed on roads and bridges in highway engineering, respectively, to obtain three-dimensional corridor models and bridge component models.

[0052] S22, Perform highway 3D modeling based on the three-dimensional corridor model and the bridge component model to obtain a BIM three-dimensional model;

[0053] S23. In Synchro 4D software, by associating the construction schedule with the BIM 3D model, time and spatial information are integrated to obtain a BIM 4D model.

[0054] The BIM 3D information model construction process based on the Benltey platform software (including S21 and S22) is as follows: Figure 3 As shown, specifically:

[0055] In OpenRoad Designers software, the CAD two-dimensional topographic map of the highway section is edited by filtering contour points and contour lines to construct a three-dimensional digital topographic map, and the highway horizontal and vertical profile lines are drawn on the basis of the three-dimensional digital topographic map.

[0056] In OpenRoad Designers software, a 3D digital topographic map with road horizontal and vertical lines is used as a reference. The road cross section template is constructed by building blocks. Then, auxiliary facilities and end conditions are added to the road cross section template for layout to form a complete road template and create a 3D corridor model.

[0057] The 3D digital topographic map with the road horizontal and vertical lines drawn is connected from the OpenRoadDesigners software to the bridge design file of the OpenBridge Modeler software by reference. The bridge component template is constructed in the OpenBridgeModeler software with the 3D digital topographic map with the road horizontal and vertical lines drawn as a reference. The main beam is laid out according to the bridge component template to construct the bridge component model.

[0058] A custom template library is extracted from the OpenBridge Modeler software and imported into Microstation. A detailed model of the bridge and a model of the bridge ancillary facilities are constructed in Microstation according to the specific parameters of the design drawings. The detailed model of the bridge and the model of the bridge ancillary facilities are then stored in the custom template library to generate a detailed template of the bridge and a template of the bridge ancillary facilities.

[0059] In the OpenBridge Modeler software, the bridge refinement template and bridge ancillary facility template built in the custom template library are placed in the preset positions of the bridge component model to generate a complete bridge model. The three-dimensional corridor model and the complete bridge model are then imported into Microstation to generate a BIM three-dimensional model.

[0060] For road visualization modeling, OpenRoad Designers software was used. This software perfectly integrates all the functions of InRoads, GEOPAK, MX, and Power Civil, while introducing a brand-new comprehensive modeling environment. The CAD 2D topographic map of a section of the highway was edited by filtering contour points and contour lines to construct a 3D digital topographic map, representing the terrain in 3D space and overcoming the limitations of traditional 2D topographic maps. Next, the highway horizontal and vertical profile lines were drawn based on the 3D digital topographic map. The horizontal profile lines were drawn using the intersection method, which involves connecting three intersection points to precisely locate the positions of two straight lines, and inserting circular and transition curves at the intersection points to create smooth, flowing horizontal lines. The vertical profile lines were drawn primarily based on the ground lines, completed by inputting the slope, station number, and vertical curve radius. The road cross-section template was constructed using a "building block" approach, with each "block" mutually constrained by "constraint points," and additional facilities and end conditions were added for layout, forming a complete road template and creating a 3D corridor.

[0061] For highway bridge sections, this invention utilizes OpenBridge Modeler software for bridge visualization modeling. Firstly, the 3D digital terrain, horizontal lines, and vertical lines of the road can be directly linked from OpenRoadDesigners software to the bridge design file for bridge visualization modeling. For the main girder structure of the bridge, after determining the corresponding parameter constraints, the parametric design of the bridge superstructure is achieved through the software's parameter constraints and control points. Finally, the key points for the placement of the substructure are defined. For bridge piers, abutments, and ancillary facilities, due to the increasing complexity of bridge structural shapes and the limited localization of OpenBridge Modeler, not all bridge structural types can be fully accommodated. Therefore, this invention extracts a custom template library from OpenBridge Modeler and creates it in Microstation. First, the 2D cross-sectional shape is drawn in Microstation, then the 3D shape of the bridge components is created using extrusion construction, and finally, commands such as placement paths are defined to create parametric solids of the components.

[0062] The creation process of a BIM 4D model (S23) is as follows: Figure 4 As shown, specifically:

[0063] By using a plugin to associate Microstation with Synchro 4D software, and running the MDL application in the Microstation command window, and adding the synchroolunpin.dll program, the BIM 3D model can be exported in the SPX file format specific to Synchro 4D software.

[0064] The SPX file format BIM 3D model is imported into Synchro 4D software. Combined with the highway construction schedule, the task is constructed using the planning module in Synchro 4D software. The construction schedule is manually entered into the Gantt chart, and components are assigned to the corresponding task's 3D resources by allocating resources. This establishes the association between the schedule and the BIM 3D model, thereby creating a BIM 4D model.

[0065] This invention utilizes Synchro 4D software for 4D model creation. Synchro 4D is a mature and powerful 4D construction simulation software. By linking the construction schedule with the 3D design model, time and spatial information can be integrated into the 4D model, making abstract and difficult-to-understand construction plans more intuitive and providing significant practical value for optimizing construction management. A plugin connects Microstation and Synchro 4D, and the MDL application is run in the Microstation command window. The synchroolunpin.dll program is added and entered, thereby exporting the BIM 3D model in Synchro 4D's proprietary SPX file format. After importing the model into Synchro 4D, tasks are constructed using the software's planning module, combining the highway construction schedule with the actual site conditions. The construction schedule is manually entered into the Gantt chart, and components are assigned to the corresponding 3D resources of the tasks through resource allocation. This establishes a link between the schedule and the 3D model, thus achieving the creation of the 4D model. Finally, by using appearance configuration files, 4D review and other related settings, the construction progress is simulated and animated for display, freeing relevant personnel from complex construction drawings and tables.

[0066] Progress Analysis:

[0067] Specifically, S3 is...

[0068] S31, a reality model progress analysis plugin developed based on the Bentley Microstation Connectedition Update 4 platform; wherein, the reality model progress analysis plugin consists of three major modules: "Construction Tree", "Comparison Model" and "Report";

[0069] S32, in the "Construction Tree" section of the real-world model progress analysis plugin, the BIM components in the BIM 3D model are assigned to the smallest units by defining the parent-child node relationship, and the smallest envelope is generated with the BIM components of the smallest unit as the boundary.

[0070] S33, in the "Comparison Model" section of the real-scene model progress analysis plugin, the three-dimensional real-scene model is subjected to Boolean difference operation on the minimum envelope, thereby giving the three-dimensional real-scene model a boundary, so that the BIM three-dimensional model matches the three-dimensional real-scene model; based on the matching, the three-dimensional real-scene model is used to segment the BIM three-dimensional model by performing Boolean sum operation on the minimum unit and the new envelope generated after the Boolean difference operation, and the segmentation result is calculated and analyzed to obtain the construction progress report;

[0071] The segmentation result includes the volume of the intersection obtained after Boolean summation and the volume of the smallest unit generated by the BIM component. The ratio between the volume of the intersection obtained after Boolean summation and the volume of the smallest unit generated by the BIM component is used to characterize the completion rate of the project components. The specific process of Boolean difference operation is as follows: the smallest envelope is cut using the 3D reality model as the cutting surface to generate a new envelope. The cutting part of the 3D reality model participating in the Boolean difference operation is a boundary given to the 3D reality model. By cutting the 3D reality model with all the smallest units, the BIM 3D model is matched with the 3D reality model. The Boolean summation operation between the new envelope and the smallest unit means that only the intersection of the new envelope and the smallest unit is retained, and the other parts are cut off.

[0072] S34. In the "Reports" section of the real-world model progress analysis plugin, the construction progress report is incorporated into the BIM four-dimensional model to achieve construction progress monitoring.

[0073] Matching and segmenting 3D reality models with BIM 3D models is a key technology for achieving automated monitoring of construction progress. Therefore, a reality model progress analysis plugin was developed based on the Bentley Microstation Connectedition Update 4 platform. This plugin uses a Boolean algorithm to quickly match the two models. Based on the matching, the 3D reality model is used to segment the BIM 3D model, and the segmentation results are calculated, analyzed, and exported as reports to generate construction progress reports. The reality model progress analysis plugin can quickly match 3D reality models with the project's BIM 3D model to achieve project progress analysis and quantity surveying, featuring simple operation and high matching efficiency.

[0074] The real-world model progress analysis plugin consists of three main sections: "Construction Tree," "Comparison Model," and "Reports." Figure 5 As shown. The "Building Tree" function of the Reality Model Progress Analysis plugin can not only quickly set the root node, parent node, and road and bridge building tree of the component tree, and name, select, and connect specific components to specific BIM units, but also assign geometric and functional attributes such as surface layer, base layer, main beam, and pier body to the components, thereby effectively classifying and summarizing the various basic elements of the decomposition structure of the highway project.

[0075] Secondly, the "Real-Scene Matching Cut Element Generator" in the "Comparison Model" can automatically match and generate envelopes from the smallest units in the construction tree, thus performing Boolean operations. An envelope can be understood as a closed surface, but it also possesses the characteristics of a solid, such as volume and density. Surfaces have far greater cutting and trimming capabilities than solids and can be transformed into solids through Boolean operations. Furthermore, considering the inherent errors in the 3D real-scene model itself and the matching process of the real-scene model progress analysis plugin, the plugin allows for manual adjustment to improve matching accuracy and reduce errors. Based on the actual situation, the size of the smallest envelope generated in the initial matching can be fine-tuned, and then the real-scene model cutting generator is used to readjust and match the modified construction, thereby improving matching accuracy.

[0076] The final "Reports" function displays the project progress analysis results in the form of data tables, line graphs, and pie charts. Data tables can also be exported to Excel. After data processing, the actual construction progress is obtained and compared with the construction schedule plan based on the 4D model built using Synchro 4D software. Based on deviations, adjustments are made to construction procedures or resource allocation in a timely manner, and the modified information is updated in the 4D model, achieving dynamic management of the construction progress and ensuring the project is completed on schedule.

[0077] The method of the present invention will be illustrated below with specific examples:

[0078] Using the Pingnan Expressway section from K114+600 to K116+200 in Guangxi Zhuang Autonomous Region, a DJI Phantom 4RTK multi-rotor drone equipped with a RIY-D2M five-lens camera from Rebo Technology was used to collect on-site information data. This camera features automatic parameter adjustment and automatic redundant image removal. A phase control point was placed every 200 meters along both sides of the highway, resulting in 11,195 photos. A 3D reality model was reconstructed using Context Capture software on the Bentley platform, with the model's accuracy controlled within 5cm. Figure 6 This is a 3D reality model of the first phase of construction on the Pingnan Expressway, from chainage K114+600 to K116+200. Figure 7This is a black-and-white grid 3D reality model of the first phase of construction of the Pingnan Expressway from chainage K114+600 to K116+200.

[0079] First, BIM 3D models of roads and bridges in the aerial survey area were created using OpenRoad Designers, OpenBridge Modeler, and Microstation software under the Bentley platform. The BIM 3D models were then imported into the Microstation platform in DNG format. A partial view of the BIM 3D model of the construction section of the Pingnan Expressway from chainage K114+600 to K116+200 is shown below (the original image is too large; only a partial illustration is shown here). Figure 8 As shown; FBX format block meshes are exported from the 3D reality model created by Context Capture software, and then imported sequentially into the Microstation platform in mesh form to complete the fusion of the BIM 3D model and the 3D reality model; as shown Figure 9 The image shown is a partial view of the fusion of the 3D reality model and the BIM 3D model of the first phase of the construction section from chainage K114+600 to K116+200 of the Pingnan Expressway (the original image is too large, so only a partial illustration is shown here).

[0080] Based on the BIM 3D model, a BIM 4D model (referred to as the 4D model) was created using Synchro 4D software. Different building growth patterns were set according to project requirements and the construction schedule, and distinguished by different colors, thus achieving a coupling relationship between the BIM 3D model and the construction schedule. Finally, the software's 4D inspection function was used to simulate highway construction, providing a basis for construction management and schedule optimization.

[0081] Based on the method of this invention, after integrating the BIM 3D model and the 3D reality model, the reality model progress analysis plugin is used to define, match, segment, calculate and analyze the attributes of the model components, and finally generate a construction progress report.

[0082] By incorporating construction progress reports into the construction progress simulation (BIM 4D model) and comparing the data in the reports with the planned progress in the 4D model, it was found that the construction progress was significantly behind schedule, with many guardrails still under construction. At the current pace, the planned progress targets cannot be met. Feedback investigation revealed that the main reasons were insufficient personnel in bridge engineering, inadequate machinery, and the large volume of earthwork excavation work in the mountains adjacent to the bridge, making it difficult to monitor the excavation progress. Therefore, the first priority is to increase the manpower and machinery input for the bridge project to ensure that the key control points are completed according to the construction plan milestones. The actual progress will be updated using the progress update function in the software's planning module, thereby allowing for real-time monitoring of the on-site construction progress.

[0083] Secondly, addressing the issue of large-scale mountain excavation projects and the difficulty in controlling the progress, this invention utilizes drones to conduct secondary filming of the construction site. Figure 10 This is a 3D reality model of the second phase of construction of the Pingnan Expressway, from chainage K114+600 to K116+200. Figure 11 This document presents a black-and-white grid 3D reality model of the second phase of the Pingnan Expressway construction section from chainage K114+600 to K116+200. By comparing and analyzing the two phases of 3D reality models (the first and second phases), the precise earthwork excavation volume is calculated, providing data reference for monitoring the mountain excavation progress. Point cloud data was generated from both phases of the 3D reality models using the OpenRoadDesigners reality model module. Triangular mesh topographic maps were then extracted from the point clouds, and finally, the mountain terrain was cropped to calculate the earthwork excavation volume.

[0084] By comparing on-site surveys with the real-world model, certain errors were found in the point cloud data generation process. For example, vegetation, buildings, and vehicles were sometimes mistaken for ground points. These errors can affect earthwork excavation calculations and require correction before calculation. Therefore, this study employed a visual manual correction method to remove erroneous point clouds, significantly reducing the impact of debris on earthwork calculations and improving accuracy.

[0085] Compared to traditional methods that rely on manual monitoring of construction progress, this invention enables rapid, automatic, and accurate monitoring of construction progress. By comparing the monitoring results with a 4D construction progress simulation, delays in construction work become readily apparent, allowing relevant personnel to promptly identify the causes and adjust subsequent construction schedules. Combined with the real-time updated 4D construction progress simulation, the entire project's construction can be intuitively reflected, enabling dynamic control of construction progress and optimized use of resources.

[0086] Based on the above-mentioned construction progress monitoring method based on the combination of oblique photogrammetry and BIM, the present invention also provides a construction progress monitoring system based on the combination of oblique photogrammetry and BIM.

[0087] like Figure 12 As shown, the construction progress monitoring system based on oblique photography and BIM includes the following modules:

[0088] A 3D reality model building module is used to acquire aerial survey data of the construction site using UAV oblique photography technology, and to build a 3D reality model based on the aerial survey data.

[0089] The BIM model building module is used to model the construction site using BIM technology to obtain a BIM three-dimensional model, and to assign time attributes to the BIM three-dimensional model to obtain a BIM four-dimensional model.

[0090] The progress analysis module is used to match the 3D reality model with the BIM 3D model using a Boolean algorithm. Based on the matching, the 3D reality model is used to segment the BIM 3D model, and the segmentation results are calculated and analyzed to obtain a construction progress report. The construction progress report is then incorporated into the BIM 4D model to achieve construction progress monitoring.

[0091] The specific functions of each module in the system of the present invention are described in the steps of the method of the present invention, and will not be repeated here.

[0092] Based on the above-mentioned construction progress monitoring method combining oblique photography and BIM, the present invention also provides a computer-readable storage medium.

[0093] A computer-readable storage medium storing a computer program that, when executed by a processor, implements the aforementioned construction progress monitoring method based on oblique photography and BIM integration.

[0094] This invention utilizes the Microstation platform to develop a real-scene model progress analysis plugin. Through the fusion, matching, segmentation, and analysis of 3D real-scene models and BIM 3D models, it enables monitoring of highway construction progress. The plugin extracts point clouds from the two phases of the 3D real-scene models and converts them into triangular mesh terrain for earthwork calculation, deriving the amount of earthwork excavation and providing data support for the mountain excavation progress. Engineering verification shows that: First, the developed real-scene model progress analysis plugin effectively combines the 3D real-scene model and the BIM model, ensuring a good connection between the BIM information model and the construction site. Second, the plugin uses efficient algorithms to accurately match, segment, calculate, and analyze the real-scene model and the engineering BIM 3D model, generating a clear project progress report to obtain the actual construction progress of the highway. By combining this with 4D simulated construction progress, it achieves both real-time monitoring of highway construction progress and real-time tracking and dynamic adjustment of the progress plan, ensuring on-time project delivery. Furthermore, by correcting and calculating the point clouds of the two phases of the 3D real-scene models, the impact of obstructions from mountainous debris on earthwork accuracy can be reduced. This method not only solves the problem that relying solely on BIM 3D models can easily deviate from the actual site conditions, but also avoids subjective errors caused by manually matching 3D reality models with BIM 3D models, effectively improving the accuracy and automation of construction progress monitoring.

[0095] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A construction progress monitoring method based on the combination of oblique photography and BIM, characterized in that: The method comprises the following steps of: S1, obtaining aerial survey data of a construction site by using a UAV oblique photography technology, and constructing a three-dimensional real scene model according to the aerial survey data; S2, modeling the construction site by using a BIM technology to obtain a BIM three-dimensional model, and giving a time attribute to the BIM three-dimensional model to obtain a BIM four-dimensional model; S3, matching the three-dimensional real scene model and the BIM three-dimensional model by using a Boolean algorithm, cutting the BIM three-dimensional model by using the three-dimensional real scene model on the basis of the matching, and calculating and analyzing the cutting result to obtain a construction progress report; and participating the construction progress report in the BIM four-dimensional model to realize construction progress monitoring; The construction progress monitoring method is particularly used for monitoring highway engineering project progress. The S2 is specifically, S21, respectively performing road visual modeling and bridge visual modeling on roads and bridges in the highway engineering based on a Bentley platform software to correspondingly obtain a three-dimensional corridor model and a bridge component model; S22, performing highway 3D modeling according to the three-dimensional corridor model and the bridge component model to obtain a BIM three-dimensional model; S23, in Synchro 4D software, integrating time information and space information by associating construction plan progress with the BIM three-dimensional model to obtain a BIM four-dimensional model; The S21 is specifically, S211, editing a CAD two-dimensional topographic map of a highway road section in an OpenRoad Designers software in a manner of screening contour points and contour lines to construct a three-dimensional digital topographic map, and drawing highway plane lines and longitudinal section lines on the basis of the three-dimensional digital topographic map; S212, constructing a road cross-section template by a building block method with reference to the three-dimensional digital topographic map with the drawn highway plane lines and longitudinal section lines in the OpenRoad Designers software, and adding accessory facilities and end conditions for lofting in the road cross-section template to constitute a complete road template and create a three-dimensional corridor model; S213, connecting the three-dimensional digital topographic map with the drawn highway plane lines and longitudinal section lines from the OpenRoad Designers software to a bridge design file of OpenBridge Modeler software by a reference method, and constructing a bridge component template with reference to the three-dimensional digital topographic map with the drawn highway plane lines and longitudinal section lines in the OpenBridge Modeler software, and performing main beam lofting according to the bridge component template to construct a bridge component model; The S22 is specifically, S221, extracting the custom template library from the OpenBridge Modeler software into the Microstation, and constructing a bridge refined model and a bridge auxiliary facility model in the Microstation according to specific parameters of design drawings, and storing the bridge refined model and the bridge auxiliary facility model into the custom template library, to generate a bridge refined template and a bridge auxiliary facility template; S222, placing the bridge refined template and the bridge auxiliary facility template constructed in the custom template library in the openbridge modeler software in a preset position of a bridge component model, to generate a complete bridge model, and importing the three-dimensional gallery model and the complete bridge model into the Microstation to generate a BIM three-dimensional model; The S23 is specifically, S231, associating the Microstation with the Synchro 4D software by using a plug-in, and running an MDL application in a Microstation command window, and adding a synchroolunpin.dll program for typing, to export the BIM three-dimensional model in an SPX file format special for the Synchro 4D software; S232, importing the BIM three-dimensional model in the SPX file format into the Synchro 4D software, combining a construction progress schedule of the expressway, constructing a task by using a plan block in the Synchro 4D software, manually inputting the construction progress schedule into a Gantt chart, and distributing components to 3D resources of corresponding tasks by a way of allocating resources, to realize association between a schedule plan and the BIM three-dimensional model, thereby creating a BIM four-dimensional model; The S3 is specifically, S31, developing a real scene model progress analysis plug-in based on a Bentley Microstation Connect edition update 4 platform; wherein the real scene model progress analysis plug-in is composed of three blocks of "construction tree", "comparison model" and "report"; S32, in the "construction tree" block of the real scene model progress analysis plug-in, distributing BIM components in the BIM three-dimensional model as minimum units by defining a child-parent node relationship, and generating a minimum envelope body with the BIM components of the minimum units as boundaries; S33, in the "contrast model" block of the real scene model progress analysis plug-in, performing a Boolean difference operation on the three-dimensional real scene model and the minimum envelope, so as to give the three-dimensional real scene model a boundary, and make the BIM three-dimensional model match the three-dimensional real scene model; on the basis of matching, the BIM three-dimensional model is cut by the three-dimensional real scene model through a Boolean sum operation of the minimum unit and the new envelope generated after the Boolean difference operation, and the cutting result is calculated and analyzed to obtain a construction progress report; wherein the cutting result includes the intersection part volume obtained after the Boolean sum operation and the minimum unit volume generated by the BIM component, and the ratio between the intersection part volume obtained after the Boolean sum operation and the minimum unit volume generated by the BIM component is used to represent the project component completion rate; S34, in the "report" block of the real scene model progress analysis plug-in, the construction progress report is involved in the BIM four-dimensional model to realize construction progress monitoring; In the process of generating the minimum envelope in S32, According to the actual situation, the size of the minimum envelope generated by the first matching is fine-tuned, and then the modified construction is readjusted and matched by using the real scene model cutting generator to obtain the final minimum envelope. 2.The construction progress monitoring method based on the combination of oblique photography and BIM according to claim 1, characterized in that: The S1 specifically comprises, S11, on-site surveying and layout of image control points are performed at the construction site; S12, according to the construction site surveying, a flight route is designed, so that the unmanned aerial vehicle carrying five cameras flies according to the designed flight route, and the five cameras simultaneously take pictures from one vertical angle and four different inclined angles at the construction site to obtain aerial survey data; S13, the aerial survey data are sequentially subjected to data import, aerial triangulation and three-dimensional reconstruction to obtain an initial three-dimensional real scene model; S14, the accuracy of the initial three-dimensional real scene model is detected to determine whether the accuracy of the initial three-dimensional real scene model meets the preset model accuracy; if not, the S11 is returned for cyclic execution; if yes, the initial three-dimensional real scene model is taken as the final three-dimensional real scene model.

3. The construction progress monitoring system based on the combination of oblique photography and BIM, characterized in that: Comprise the following modules, A three-dimensional real scene model construction module is configured to obtain aerial survey data of a construction site by using an unmanned aerial vehicle tilt photography technology, and construct a three-dimensional real scene model according to the aerial survey data; A BIM model construction module is configured to model the construction site by using a BIM technology to obtain a BIM three-dimensional model, and give the BIM three-dimensional model a time attribute to obtain a BIM four-dimensional model; A progress analysis module is configured to match the three-dimensional real scene model and the BIM three-dimensional model by using a Boolean algorithm, cut the BIM three-dimensional model by the three-dimensional real scene model on the basis of matching, and calculate and analyze the cutting result to obtain a construction progress report; and involve the construction progress report in the BIM four-dimensional model to realize construction progress monitoring; The construction progress monitoring system is specifically configured to monitor the progress of a highway engineering project; The BIM model construction module is specifically configured to The Bentley platform software is used for road visual modeling and bridge visual modeling of roads and bridges in the expressway project, so as to obtain a three-dimensional corridor model and a bridge component model; Expressway 3D modeling is performed according to the three-dimensional corridor model and the bridge component model, so as to obtain a BIM three-dimensional model; In the Synchro 4D software, the construction plan schedule is associated with the BIM three-dimensional model, time information and space information are integrated, and a BIM four-dimensional model is obtained; The Bentley platform software is used for road visual modeling and bridge visual modeling of roads and bridges in the expressway project, so as to obtain a three-dimensional corridor model and a bridge component model, specifically, In the OpenRoad Designers software, a CAD two-dimensional topographic map of the expressway road section is edited in the form of screening contour points and contour lines, so as to construct a three-dimensional digital topographic map, and road plane lines and longitudinal section lines are drawn on the basis of the three-dimensional digital topographic map; In the OpenRoad Designers software, a three-dimensional digital topographic map with road plane lines and longitudinal section lines is taken as a reference, a road cross-section template is constructed in the form of building blocks, and auxiliary facilities and end conditions are added to the road cross-section template for lofting, so as to constitute a complete road template and obtain a three-dimensional corridor model; A three-dimensional digital topographic map with road plane lines and longitudinal section lines is connected from the OpenRoad Designers software to a bridge design file of the OpenBridge Modeler software in a reference manner, a bridge component template is constructed in the OpenBridge Modeler software by taking the three-dimensional digital topographic map with road plane lines and longitudinal section lines as a reference, and main beam lofting is performed according to the bridge component template, so as to obtain a bridge component model; Expressway 3D modeling is performed according to the three-dimensional corridor model and the bridge component model, so as to obtain a BIM three-dimensional model, specifically, Custom template libraries are extracted from the OpenBridge Modeler software to the Microstation, bridge refined models and bridge auxiliary facility models are constructed in the Microstation according to specific parameters of design drawings, and the bridge refined models and the bridge auxiliary facility models are stored in the custom template libraries, so as to generate bridge refined templates and bridge auxiliary facility templates; In the OpenBridge Modeler software, the bridge refined templates and the bridge auxiliary facility templates constructed in the custom template libraries are placed in preset positions of the bridge component model, so as to generate a complete bridge model, and the three-dimensional corridor model and the complete bridge model are imported into the Microstation to generate a BIM three-dimensional model; In the Synchro 4D software, the construction plan schedule is associated with the BIM three-dimensional model, time information and space information are integrated, and a BIM four-dimensional model is obtained, specifically, The BIM three-dimensional model is exported in SPX file format special for Synchro 4D software by using a plug-in to associate Microstation with Synchro 4D software, running an MDL application in a Microstation command window, and adding a synchroolunpin.dll program for typing; The BIM three-dimensional model in SPX file format is imported into Synchro 4D software, a construction progress schedule of the expressway is combined, a task is constructed by using a plan block in Synchro 4D software, the construction progress schedule is manually input into a Gantt chart, and components are distributed to 3D resources of corresponding tasks by means of allocation of resources, so that association between a schedule plan and the BIM three-dimensional model is realized, and a BIM four-dimensional model is created. The progress analysis module is specifically used for, A real scene model progress analysis plug-in is developed based on a Bentley Microstation Connectedition Update4 platform, wherein the real scene model progress analysis plug-in is composed of three blocks of "construction tree", "comparison model" and "report". In the "construction tree" block of the real scene model progress analysis plug-in, BIM components in the BIM three-dimensional model are distributed as minimum units by defining a child-parent node relationship, and a minimum envelope is generated by taking the BIM components of the minimum units as boundaries. In the "comparison model" block of the real scene model progress analysis plug-in, the three-dimensional real scene model is subjected to a Boolean difference operation on the minimum envelope, so that the three-dimensional real scene model is given a boundary, the BIM three-dimensional model is matched with the three-dimensional real scene model, on the basis of the matching, the BIM three-dimensional model is cut by the three-dimensional real scene model by performing a Boolean sum operation on the minimum units and a new envelope generated after the Boolean difference operation, and a construction progress report is obtained by calculating and analyzing a cutting result; wherein the cutting result includes a volume of an intersection part obtained after the Boolean sum operation and a volume of the minimum units generated by the BIM components, and a ratio between the volume of the intersection part and the volume of the minimum units generated by the BIM components is used to represent a completion rate of project components; In the "report" block of the real scene model progress analysis plug-in, the construction progress report is involved in the BIM four-dimensional model, and construction progress monitoring is realized. In the process of generating the minimum envelope, the size of the minimum envelope generated by the first matching is finely adjusted according to actual conditions, and then the modified construction is readjusted and matched by using a real scene model cutting generator, so that the final minimum envelope is obtained.

4. A computer readable storage medium storing a computer program, characterized in that: When the computer program is executed by the processor, the construction progress monitoring method based on the combination of oblique photography and BIM is realized.

Images