Infrastructure structure inspection system and infrastructure structure inspection program

Abstract

To provide a system and program that can visually display the deterioration status of infrastructure structures in an easy-to-understand manner without damaging them. [Solution] A system 10 that can input point cloud data D1 obtained by 3D scanning an infrastructure structure, comprising: a function to create TIN model data T1 from the point cloud data D1; and a function to compare the TIN model data T1 and the point cloud data D1, and create analysis data A1 by coloring each point in the point cloud data D1 with different hues depending on whether it protrudes from the surface of the TIN model data T1 at the corresponding location or is recessed from the surface of the TIN model data T1 at the corresponding location.

Description

Technical Field

[0001] The present invention relates to a system and a program for inspecting the surface condition of infrastructure, particularly concrete structures.

Background Art

[0002] For concrete structures, which are infrastructure represented by bridges and tunnels, etc., it is obligatory to conduct regular inspections once every five years. As a conventional method for inspecting concrete structures, in addition to visual inspection, checking the impact sound by hitting the concrete surface with a hammer has been carried out.

[0003] However, in inspection by impact sound, it is difficult to judge the deterioration of concrete unless the operator has accumulated experience, and it is also conceivable that the judgment may vary depending on the operator.

[0004] Therefore, Patent Document 1 discloses a method of converting the impact sound of a concrete structure into digital waveform data, performing time-frequency analysis to generate impact sound analysis data, plotting the impact sound analysis data in a three-dimensional impact sound analysis space, and judging the presence and degree of deterioration of the concrete structure.

[0005] In addition, Patent Document 2 discloses a method of drilling holes in a concrete structure with a hammer drill, measuring the drilling depth, the resistance index of the hammer drill, the rebound hardness, the original waveform, the reflected wave and the transmitted wave of the elastic wave caused by the impact of the hammer drill, and diagnosing the deterioration of the concrete structure based on these.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Summary of the Invention

[0007] The methods disclosed in Patent Documents 1 and 2 mentioned above have the problem that the results may vary depending on where on the concrete structure the impact is applied. There was also a request to visually display the deterioration status of concrete structures in an easy-to-understand way. [Means for solving the problem]

[0008] Therefore, the present invention has been made to solve the above problems, and its objective is to provide a system and program that can visually display the deterioration status of infrastructure structures in an easy-to-understand manner without damaging them.

[0009] The infrastructure structure inspection system according to the present invention is a system that can input point cloud data obtained by 3D scanning an infrastructure structure, and is characterized by comprising: a function to create TIN model data from the point cloud data; and a function to compare the TIN model data with the point cloud data and create analysis data by coloring each point in the point cloud data with different hues depending on whether it protrudes from the surface of the TIN model data at the corresponding location or is recessed from the surface of the TIN model data at the corresponding location. By adopting this configuration, it is possible to immediately identify points in the analysis data that protrude beyond the surface of the TIN model data, indicating delamination or spalling on the concrete surface of the infrastructure structure, and points that recess below the surface of the TIN model data, indicating spalling or exposed rebar on the concrete surface of the infrastructure structure.

[0010] Furthermore, the function for creating the analysis data is characterized by coloring each point in the point cloud data with a gradient according to its distance from the corresponding location in the TIN model data, in cases where the point protrudes from the surface of the TIN model data at the corresponding location, and in cases where the point is recessed from the surface of the TIN model data at the corresponding location. This configuration allows for a quick assessment of the extent of damage to concrete structures, for example, by using shades of the same hue.

[0011] Furthermore, the system is characterized by having a function to calculate the volume of a recessed area when each point in the point cloud data is recessed compared to the surface of the TIN model data at the corresponding location. This configuration makes it easy to determine the amount of concrete needed to repair the damaged area.

[0012] Furthermore, the system is characterized by having a function that allows the operator to mark the point cloud data and creates analysis data such that the markings are also displayed on the analysis data. With this configuration, saving the analysis data will be useful in identifying how damage has changed over time when assessing damage to the same location in subsequent years. [Effects of the Invention]

[0013] According to the present invention, a system and program can be created that generates visually easy-to-understand data on the deterioration status of infrastructure structures without damaging the infrastructure structures. [Brief explanation of the drawing]

[0014] [Figure 1] This is an explanatory diagram showing the overall configuration of the infrastructure structure inspection system in this embodiment. [Figure 2] This is a block diagram showing the internal structure of a computer. [Figure 3] This is a flowchart of the infrastructure structure inspection program in this embodiment. [Figure 4] It is an explanatory diagram showing an example of point group data. [Figure 5] It is an explanatory diagram showing an example of TIN model data. [Figure 6] It is an explanatory diagram showing an example of analysis data. [Figure 7] It is a comparison diagram comparing the surface of an actual infrastructure with analysis data. [Figure 8] It is an explanatory diagram of a case where only the portions protruding from the reference plane of the TIN model data are displayed. [Figure 9] It is an explanatory diagram showing a case where markings made by an operator are displayed on the analysis data. [Figure 10] It is an explanatory diagram showing a case of detecting the depth of the recessed portions at the peeling portions and the locations where the reinforcing bars are exposed. [Figure 11] It is an explanatory diagram showing a case of calculating the volume of the recessed portions at the peeling portions and the locations where the reinforcing bars are exposed. [Figure 12] It is an explanatory diagram showing Application Example 1. [Figure 13] It is an explanatory diagram showing Application Example 2.

Mode for Carrying Out the Invention

[0015] Hereinafter, referring to the drawings, the inspection system and program for infrastructure in the present embodiment will be described. As a specific infrastructure, an embodiment of a concrete structure will be described. Fig. 1 shows a schematic configuration diagram of the entire system. The inspection system 10 is basically composed of a computer 20 including a monitor 22. The 3D scanning of the structure is performed by a laser scanner 12. As the laser scanner 12, a known one can be adopted.

[0016] The objects to be 3D scanned by the laser scanner 12 are concrete structures such as bridges and tunnels. The results of the 3D scan by the laser scanner 12 are constructed as point cloud data within the laser scanner 12. The point cloud data is input to the computer 20 via a communication line 11 such as the internet, or input to the computer 20 via a recording medium 14 such as a portable memory without using the communication line 11.

[0017] Figure 2 shows the internal structure of a computer. The computer 20 can be a standard personal computer and includes a control unit 24 which includes a CPU as a central processing unit and memory such as ROM and RAM, a storage unit 26 which consists of an SSD or hard disk drive, an input unit 28 which consists of a mouse and keyboard, and a monitor 22.

[0018] The control unit 24 controls the overall operation of the computer 20 and executes and controls the functions based on each program stored in the memory unit 26. The computer 20 may also be equipped with a graphics card that includes a GPU.

[0019] The memory unit 26 stores the concrete structure inspection program P1 (hereinafter simply referred to as the inspection program). The control unit 24 reads and executes the inspection program P1 to realize the operations defined in the inspection program P1. The storage unit 26 also stores point cloud data D1 measured by the laser scanner 12. As described above, the point cloud data D1 is input to the computer 20 via the communication line 11 or the recording medium 14.

[0020] Next, the operation of the inspection program P1 will be explained based on Figures 3 to 6. Figure 4 is an example of point cloud data, Figure 5 is an example of TIN model data, and Figure 6 is an example of analysis data. When the control unit 24 reads and executes the inspection program P1, the control unit 24 performs the function of creating TIN model data T1 from the point cloud data D1 (step S101). TIN (Triangular Irregular Network) is an irregular triangular network. The control unit 24 estimates the edge portions of the point cloud data D1, and arranges triangles so that the edge portions become the sides of triangles, thereby creating TIN model data T1.

[0021] Next, the control unit 24 compares the created TIN model data T1 with the point cloud data D1 to create analysis data A1 (step S102). Analysis data A1 is created by a difference analysis between TIN model data T1 and point cloud data D1. Specifically, the control unit 24 creates analysis data A1 by coloring each point in the point cloud data D1 with a different hue depending on whether the point in the point cloud data D1 protrudes from the reference plane of the TIN model data T1 at the corresponding location, or whether it is recessed from the reference plane of the TIN model data T1 at the corresponding location. Furthermore, by setting the minimum difference distance detectable by the control unit 24 to 1 mm, it becomes possible to identify irregularities that cannot be perceived with the naked eye using the analysis data A1.

[0022] For example, the control unit 24 colors a point in the point cloud data D1 red if it protrudes from the reference plane of the TIN model data T1 at the corresponding location, and blue if it is recessed from the reference plane of the TIN model data T1 at the corresponding location. As a result, when the analysis data A1 is displayed on monitor 22, the red areas can be identified as areas where concrete lifting, bulging, or swelling has occurred. The blue areas can be identified as areas where concrete spalling, exposed rebar, defects, or settlement has occurred.

[0023] Furthermore, when creating the analysis data A1, the control unit 24 applies a gradient color to each point in the point cloud data according to its distance from the corresponding position in the TIN model data, in cases where the point protrudes from the surface of the TIN model data at the corresponding position, and in cases where the point is recessed from the surface of the TIN model data at the corresponding position.

[0024] For example, if points that protrude from the reference plane of the TIN model data T1 are colored red as described above, points will be colored orange as the protrusion distance is small, and dark red as the protrusion distance is large. Also, if points that are recessed from the reference plane of the TIN model data T1 are colored blue as described above, points will be colored light blue as the protrusion distance is small, and dark blue as the protrusion distance is large.

[0025] Figure 7 shows a comparison between the surface of an actual concrete structure and the case where surface irregularities are introduced in the analysis data A1. The left side of Figure 7 is a photograph of the surface of an actual concrete structure, and the right side is an image represented by the analysis data A1. In addition, in Figure 7, the irregularities of the point cloud data D1 relative to the reference plane of the TIN model data T1 are analyzed to a degree of ±0.02m.

[0026] According to Figure 7, areas of honeycombing (where aggregate has accumulated in large quantities), P-con holes (holes used to seal separators during concrete placement), spalling, exposed rebar, and delamination are shown in blue, with areas of delamination and exposed rebar being particularly dark blue, allowing for easy identification of damaged areas. On the other hand, areas of spalling and free lime are shown in red, with areas of particularly large spalling being dark red, also allowing for easy identification of damaged areas.

[0027] Furthermore, the inspection program P1 also has the function of displaying only one of the following: either the locations in the analysis data A1 that protrude above the reference plane of the TIN model data T1, or the locations in the analysis data A1 that are recessed below the reference plane of the TIN model data T1. Figure 8 shows an example where only the areas protruding from the reference plane of the TIN model data T1 are highlighted in red. As shown in Figure 8, it is immediately clear that the areas highlighted in dark red are at risk of delamination.

[0028] Furthermore, if only one of the following is to be displayed: either the portion of the analysis data A1 that protrudes above the reference plane of the TIN model data T1, or the portion of the analysis data A1 that is recessed above the reference plane of the TIN model data T1, the control unit 24 should display selectable options on the monitor 22, allowing the operator to select either the protruding or recessed portion by operating the input unit 28 (not shown).

[0029] Furthermore, the inspection program P1 also has a function that allows markings made by the worker to be displayed on the analysis data A1. The upper part of Figure 9 shows the point cloud data D1 with markings applied by the operator (specifically, areas of damage enclosed in a rectangular frame), while the lower part of Figure 9 shows the analysis data A1 with the markings reflected in the display.

[0030] This function allows the operator to mark the point cloud data D1 on the monitor 22 using the input unit 28, and the control unit 24 then controls the system to display these markings directly on the analysis data A1. The control unit 24 also allows the operator to select the marking color. Therefore, the operator can use different colors to mark depending on the type and condition of the damage. In this way, by reflecting the markings in analysis data A1, if this analysis data A1 is retained, it becomes easy to understand the changes over time based on analysis data A1.

[0031] Furthermore, inspection program P1 also has the function to detect the depth of depressions in areas of spalling and exposed rebar in the point cloud data D1. While inspection program P1 already colors the analysis data A1 based on depth when creating it, this function allows it to show the worker specific depth values. The upper part of Figure 10 shows the operator identifying a location in the point cloud data D1 for which they want to know the depth. The lower part of Figure 10 shows the calculated depth displayed. When the point cloud data D1 is displayed on the monitor 22, the control unit 24 controls the system to calculate the depth of the depression below the line when the operator draws a straight line at a location where the depth is to be determined by operating the input unit 28, and to display the calculated distance on the monitor 22.

[0032] Furthermore, inspection program P1 has a function to calculate the volume of depressions in areas where concrete has spalled or where rebar is exposed. By calculating the volume of depressions in areas where concrete has spalled or where rebar is exposed, the amount of concrete repair required can be determined. Figure 11 shows the point cloud data D1, displaying the areas where the operator wants to know the depth (darkly colored areas) and the calculated volume. When the control unit 24 is displaying the point cloud data D1 on the monitor 22, and the operator uses the input unit 28 to indicate a spalled area or exposed rebar, the control unit 24 divides the area inside the indicated location into a small grid and calculates the volume based on the sum of the small grids. The control unit 24 then displays the calculated volume on the monitor 22.

[0033] Furthermore, the inspection program P1 also has a function to calculate the area of ​​the damaged area (not shown). When the control unit 24 is displaying the point cloud data D1 on the monitor 22, and the operator uses the input unit 28 to indicate a damaged area, the control unit 24 calculates the area based on the perimeter of the damaged area and displays the calculated area on the monitor 22.

[0034] Furthermore, the inspection system 10 and inspection program P1 of this embodiment can be used for the following purposes. (Example 1) Figure 12 shows an example of its use. At construction sites for tunnel lining, thickening methods, spraying, etc., point cloud data D1 is acquired before construction, and TIN model data T1 is created from the pre-construction point cloud data D1 and stored in the storage unit 26. The control unit 24 then acquires the point cloud data D1 after construction, performs a difference analysis between the pre-construction TIN model data T1 stored in the storage unit 26 and the post-construction point cloud data D1, and creates analysis data A1 between the post-construction point cloud data D1 and the pre-construction TIN model data T1. According to this analysis data A1, it is possible to determine how much thicker the tunnel became after construction compared to before construction, thus verifying the construction methods such as tunnel lining, thickening methods, and spraying.

[0035] (Example 2) Figure 13 shows an example of its use, Part 2. The control unit 24 pre-stores the structure's past point cloud data D1 in the storage unit 26 and creates past TIN model data T1 from the past point cloud data D1. Then, it acquires the structure's current point cloud data D1 and performs a difference analysis between the past TIN model data T1 and the current point cloud data D1 to create analysis data A1 between the past TIN model data T1 and the current point cloud data D1. This analysis data A1 allows us to verify changes over time in the tilt and settlement of structures.

[0036] In the embodiments described above, points protruding from the reference plane of the TIN model data T1 were colored red, and points recessed from the reference plane of the TIN model data T1 were colored blue. However, the hue is not limited to this. It is preferable to set the hue so that the protruding points and recessed points can be clearly distinguished visually. Furthermore, the inspection program P1 may have a function that allows the worker to freely set the hue.

[0037] As described above, according to this embodiment, it is possible to visualize invisible damage to concrete structures, which are infrastructure structures, using point cloud data, thereby improving efficiency at the work site.

[0038] It should be noted that the present invention is not limited to the embodiments described above, and various modifications are possible without departing from the scope of the present invention. [Explanation of Symbols]

[0039] 10 Inspection System 11 Communication lines 12 Laser Scanners 14 Recording media 20 Computers 22 monitors 24 Control Unit 26 Memory section 28 Input section A1 Analysis Data D1 Point Cloud Data P1 Inspection Program T1 TIN Model Data

Claims

1. A system that can input point cloud data obtained by 3D scanning infrastructure structures, The function to create TIN model data from the aforementioned point cloud data, An infrastructure structure inspection system characterized by comprising: a function to compare the TIN model data with the point cloud data and create analysis data by coloring each point in the point cloud data with a different hue depending on whether it protrudes from the surface of the TIN model data at the corresponding location or is recessed from the surface of the TIN model data at the corresponding location.

2. The function that generates the aforementioned analysis data is: The infrastructure structure inspection system according to claim 1, characterized in that each point in the point cloud data is colored with a gradient according to the distance from the corresponding position in the TIN model data, in cases where the point protrudes from the surface of the TIN model data at the corresponding position, and in cases where the point is recessed from the surface of the TIN model data at the corresponding position.

3. An infrastructure structure inspection system according to claim 1 or 2, characterized in that it includes a function to calculate the volume of a recessed area when each point in the point cloud data is recessed compared to the surface of the TIN model data at the corresponding location.

4. An infrastructure structure inspection system according to claim 1 or 2, characterized in that it has a function to create analysis data such that an operator can mark the point cloud data and the markings are also displayed on the analysis data.

5. A computer-readable program that can input point cloud data obtained by 3D scanning infrastructure structures, The function to create TIN model data from the aforementioned point cloud data, An infrastructure structure inspection program characterized by causing the computer to perform a function that compares the TIN model data with the point cloud data and creates analysis data by coloring each point in the point cloud data with a different hue depending on whether it protrudes from the surface of the TIN model data at the corresponding location or is recessed from the surface of the TIN model data at the corresponding location.

6. The function that generates the aforementioned analysis data is: An infrastructure structure inspection program according to claim 5, characterized in that each point in the point cloud data is colored with a gradient according to the distance from the corresponding position in the TIN model data, in cases where the point protrudes from the surface of the TIN model data at the corresponding position, and in cases where the point is recessed from the surface of the TIN model data at the corresponding position.

7. An infrastructure structure inspection program according to claim 5 or 6, characterized in that, when each point in the point cloud data is recessed compared to the surface of the TIN model data at the corresponding location, the computer is made to perform a function to calculate the volume at the recessed location.

8. An infrastructure structure inspection program according to claim 5 or 6, characterized in that the computer is made to execute a function to create analysis data such that the point cloud data can be marked by an operator and the markings are also displayed on the analysis data.

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