JP7390260B2 - Compaction state determination device and compaction state determination method - Google Patents

Description

The present invention relates to an apparatus and method for determining the compaction state of concrete materials.

When constructing civil engineering structures such as dams, roads, and embankments by heaping concrete materials, so-called compaction work is performed in which the poured concrete material is vibrated to remove air bubbles from the concrete material. Insufficient compaction (insufficient vibration) causes insufficient strength and cracks in the concrete material after hardening. Therefore, it is required to determine the compaction state and manage the compaction.

Patent Document 1 discloses that the compaction state is determined based on the excitation time.

Another method for determining the compaction state is for a worker to visually check the surface of the concrete material. In concrete materials, immediately after pouring, the aggregate floats on top of the paste, and as the compaction process progresses, the aggregate sinks into the paste, and the paste spreads uniformly over the surface of the concrete material. The surface of the concrete material becomes smooth. The worker visually checks the condition of the surface of the concrete material, such as how well the aggregate sinks into the paste, how well the paste spreads, and the smoothness of the surface of the concrete material, and determines the compaction state. .

Japanese Patent Application Publication No. 2018-193681

It is known that the vibration time required to compact concrete material varies depending on the composition of the concrete material, ambient temperature and humidity, etc. In order to determine the compaction state based on the vibration time, it is necessary to set the standard vibration time based on the mix of concrete materials, ambient temperature and humidity, etc. Patent Document 1 does not disclose a specific method for setting a reference vibration time, and is insufficient as a method for determining the compaction state.

On the other hand, there is a certain correlation between the surface condition of a concrete material and its compaction state, regardless of the composition of the concrete material, the ambient temperature and humidity, and the like. Therefore, in order to appropriately determine the compaction state, it is effective to use the surface state of the concrete material. However, there is no established method for objectively grasping the surface condition of concrete materials, and the current state of compaction is determined by workers grasping the surface condition of concrete materials with their senses. . Therefore, it largely depends on the skill level of the worker, and there is a possibility that the compaction state cannot be appropriately determined.

An object of the present invention is to appropriately determine the compaction state of concrete material.

The present invention is a compaction state determination device that determines the compaction state of a concrete material, and includes a photographing unit that photographs the surface of the concrete material and acquires image information, and an analysis unit that analyzes information on the image acquired by the photographing unit. A controller that compares brightness values or grayscale values between adjacent pixels in a predetermined region of the image, and detects pixels whose brightness values or grayscale values change by more than a predetermined threshold value between adjacent pixels. The area is identified as a changed area, and the compaction state of the concrete material is determined based on the ratio of the changed area to a predetermined area.

The present invention also provides a compaction state determination method for determining the compaction state of a concrete material, which includes a photographing step of photographing the surface of the concrete material and acquiring image information, and information of the image acquired in the photographing step. an analysis step of analyzing the brightness value or grayscale value between adjacent pixels in a predetermined region of the image, and compares the brightness value or grayscale value between the adjacent pixels to a predetermined threshold value or more. A changing pixel is identified as a changing area, and the compaction state of the concrete material is determined based on the ratio of the changing area to a predetermined area.

According to the present invention, the compaction state of concrete material can be appropriately determined.

FIG. 1 is a side view of a compaction device to which a compaction state determination device according to an embodiment of the present invention can be applied. (a) is an example of an image of the surface of concrete material immediately after pouring, (b) is an example of an image of the surface of concrete material undergoing compaction work, and (c) is an example of an image of the surface of concrete material that has been compacted. This is an example of an image of the surface of concrete material after hardening work has been completed. FIG. 1 is a block diagram of a compaction state determination device according to an embodiment of the present invention. (a) is an example of an enlarged view of an image photographed by the photographing section, and (b) is a diagram showing the result of processing by the change area identification section on the image shown in FIG. 4(a). It is. This is an example of an image displayed on the display unit.

Hereinafter, a compaction state determination device and a compaction state determination method according to an embodiment of the present invention will be described with reference to the drawings.

When constructing civil engineering structures such as dams, roads, and embankments by heaping concrete materials, so-called compaction work is performed in which the poured concrete material is vibrated to remove air bubbles from the concrete material. Concrete material is, for example, concrete produced by mixing cement, water and aggregate. The concrete material may be cement-improved soil obtained by adding cement to locally generated soil procured near the site of civil engineering work, or CSG (Cemented Sand and Gravel) material, which is obtained by adding cement and water to locally generated soil. There may be.

FIG. 1 is a side view of a compaction device 1 used for compaction work. As shown in FIG. 1, the compaction device 1 includes a traveling section 2 that can run, a swivel table 3 that is supported by the traveling section 2 so as to be pivotable around a vertical axis, and a swivel table 3 that is supported by the swivel table 3 so as to be swingable. A boom 4, an arm 5 swingably supported at the tip of the boom 4, a bracket 6 swingably supported at the tip of the arm 5, and a vibrator 7 attached to the bracket 6. . The vibrator 7 is formed into a rod shape so that it can be inserted into concrete material that has been placed. When the vibrator 7 is inserted into the concrete material in its axial direction and vibrates, the concrete material within the vibration transmission range centered on the vibrator 7 vibrates, and air forming bubbles is removed from the concrete material, causing the concrete material to vibrate. is compacted. A control room 8 is provided in the turning table 3, and a worker operates the compaction device 1 from the control room 8. The entire concrete material can be compacted by sequentially moving the vibrator 7 by driving the traveling section 2, the rotating table 3, the boom 4, and the arm 5.

Insufficient compaction (insufficient vibration) causes insufficient strength and cracks in the concrete material after hardening. Therefore, it is required to determine the compaction state and manage the compaction. Since the compaction state of the concrete material has a certain correlation with the surface state of the concrete material, it is effective to determine the compaction state of the concrete material based on the surface state of the concrete material.

Here, with reference to FIG. 2, the correlation between the compacted state of concrete material and the surface of concrete material will be explained. FIG. 2(a) is an example of an image of the surface of concrete material immediately after pouring. FIG. 2(b) is an example of an image of the surface of concrete material undergoing compaction work. FIG. 2(c) is an example of an image of the surface of concrete material after compaction work has been completed.

As shown in FIG. 2(a), immediately after the concrete material is placed, the aggregate is floating on the paste-like material. As the compaction work progresses, the aggregate sinks into the paste and the paste begins to spread on the surface of the concrete material, changing the surface of the concrete material, as shown in FIG. 2(b). Furthermore, as the compaction work progresses further from the state shown in Figure 2(b), the paste material spreads almost uniformly on the surface of the concrete material, as shown in Figure 2(c), and the surface of the concrete material becomes smooth. Become. In fact, the state shown in FIG. 2(c) is the state in which compaction of the concrete material has been completed.

In the compaction state determination device 100 and the compaction device determination method according to the present embodiment, the condition of the surface of the concrete material is detected by analyzing the information of the image obtained by photographing the surface of the concrete material, using the configuration described below. do. Therefore, the condition of the surface of the concrete material can be grasped without relying on the operator's senses, and the compaction state of the concrete material can be appropriately determined.

FIG. 3 is a block diagram of the compaction state determination device 100. As shown in FIG. 3, the compaction state determination device 100 includes a photographing section 10 that photographs the surface of a concrete material and acquires image information, a controller 20 that analyzes information on the image acquired by the photographing section 10, and a controller 10 that photographs the surface of a concrete material and acquires image information. 20.

The photographing unit 10 is, for example, a digital camera. As shown in FIG. 1, the imaging unit 10 is attached to the bracket 6 of the compaction device 1. In a state where the vibrator 7 is inserted into the concrete material, the photographing unit 10 can photograph the surface of the concrete material in the vibration transmission range.

As shown in FIG. 3, the photographing unit 10 is connected to the controller 20 by wire or wirelessly, and transmits information on acquired images to the controller 20.

The controller 20 includes a CPU (Central Processing Unit) that executes a control program, etc., a ROM (Read-Only Memory) that stores the control program executed by the CPU, and a RAM (Random Access Memory) that stores the calculation results of the CPU. ). The controller 20 may be configured by one microcomputer or multiple microcomputers. The controller 20 may be mounted on the turning table 3 (see FIG. 1) of the compaction device 1, or may be installed separately from the compaction device 1.

In areas where the paste material spreads almost uniformly over the surface of the concrete material and the surface of the concrete material is smooth, areas where the brightness and shade change compared to areas where the aggregate is floating on the paste material. Less is. Therefore, the condition of the surface of the concrete material can be detected by identifying the changing area where the brightness or darkness changes. Therefore, the controller 20 is configured to detect the surface condition of the concrete material based on changes in brightness or darkness, and to determine the compaction state of the concrete material.

Actually, a concrete material containing coarse aggregate with a maximum dimension of 25 mm and a concrete material containing coarse aggregate with a maximum dimension of 80 mm were compacted using a rod-shaped vibrator 7, and the compaction state was determined. For any of the concrete materials, by setting thresholds for brightness values or shading values, it was possible to obtain results in which the compaction state could be determined favorably. Coarse aggregate with a maximum dimension of 25 mm is generally used for reinforced concrete, and coarse aggregate with a maximum dimension of 80 mm is generally used for dam concrete.

The controller 20 includes an information acquisition section 21 that acquires information on the image sent from the photographing section 10, and processes the information acquired by the information acquisition section 21 to determine whether the brightness value or grayscale value in the image changes to a predetermined threshold value or more. a change area specifying unit 22 that specifies a change area to It includes a determination unit 24 that determines the compaction state. The information acquisition section 21, the change area identification section 22, the ratio calculation section 23, and the determination section 24 are virtual units of the functions of the controller 20.

The change area specifying unit 22 compares brightness values or grayscale values between adjacent pixels in a predetermined area of the image photographed by the photographing unit 10. The predetermined area is, for example, the entire area of the image. The predetermined area may be a partial area in the image.

When the brightness value or the gray value between mutually adjacent pixels changes by more than a predetermined threshold value, the changed area specifying unit 22 identifies the mutually adjacent pixels as a changed area. If the brightness values or gray values between mutually adjacent pixels do not change by more than a predetermined threshold value, the mutually adjacent pixels are identified as a non-change area.

The process of identifying a changed area by the changed area specifying unit 22 will be specifically described with reference to FIG. 4(a). FIG. 4A is an example of an enlarged view of an image photographed by the photographing unit 10. The diagram shown in FIG. 4A includes 10 pixels in the vertical direction and 10 pixels in the horizontal direction, for a total of 100 pixels. The brightness or darkness of a pixel is generally quantified in 256 gradations from 0 (zero) to 255, but here, for convenience of explanation, the brightness or darkness or shading is quantified in 5 gradations from 1 to 5. . Furthermore, here, pixels whose brightness values or grayscale values change by three or more gradations are specified as changing regions.

The changed area specifying unit 22 first selects one pixel from a plurality of pixels included in a predetermined area of the image. Here, it is assumed that pixel (3, 3) in FIG. 4(a) is selected. Next, the brightness value or gray value of the selected pixel (3,3) and the pixels (3,2), (2,3), (4,3), (3, 4) are compared with the brightness value or shading value. Between pixels (3, 3) and (3, 2), and between pixels (3, 3) and (3, 2), brightness values or gray values do not change; Between pixel 3) and pixel (2, 3), and between pixel (3, 3) and pixel (4, 3), the brightness value or gray value changes by three gradations. Therefore, the changed area identifying unit 22 identifies the selected pixel (3, 3) as a changed area.

When selecting the pixel (7, 7) in FIG. 4(a), the change area specifying unit 22 determines that the brightness value or the gray value is between the pixel (7, 7) and the pixel (7, 6), There is no change between pixel (7, 7) and pixel (8, 7), and there is only one gradation change between pixel (7, 7) and pixel (6, 7), There is a difference of two gradations between pixel (7, 7) and pixel (7, 8). That is, between pixel (7, 7), pixel (7, 6), pixel (6, 7), pixel (8, 7), and pixel (7, 8), the brightness value or gray value is 3. There is no change beyond the gradation. Therefore, the changed area identification unit 22 identifies the selected pixel (7, 7) as a non-changed area.

FIG. 4(b) is a diagram showing the result of processing the image shown in FIG. 4(a) by the changed area specifying unit 22. As shown in FIG. 4(b), all the pixels shown in FIG. 4(a) are specified by the changed area specifying unit 22 as either a changed area or a non-changed area.

Referring again to FIG. The ratio calculation unit 23 calculates the ratio of the changed area specified by the changed area identification unit 22 (hereinafter also referred to as “changed area ratio”). Specifically, the changed area ratio is calculated by dividing the number of pixels specified as a changed area by the changed area identification unit 22 by the total number of pixels that have been processed by the changed area identification unit 22. The smaller the change area ratio is, the larger the area where the paste-like substance spreads substantially uniformly on the surface of the concrete material and the surface of the concrete material is smooth, which means that the compaction work is progressing.

The determination unit 24 determines the compaction state of the concrete material based on the change area ratio calculated by the ratio calculation unit 23. Specifically, if the change area ratio exceeds a predetermined reference value, it is determined that compaction has not been completed. If the change area ratio is less than or equal to a predetermined reference value, it is determined that compaction has been completed.

In this manner, the controller 20 specifies, from the image of the surface of the concrete material photographed by the photographing unit 10, a changing region where the brightness value or the gray value changes by a predetermined threshold value or more. Therefore, the changing region in the image corresponds to a place where the brightness and shade change on the surface of the concrete material. Therefore, by using the ratio of the change area, the surface condition of the concrete material can be grasped without relying on the senses of the worker, and the compaction state can be appropriately determined.

The display unit 30 displays the result of the determination by the determination unit 24. As shown in FIG. 1, the display unit 30 is provided in the operator's room 8, and the operator can operate the compaction device 1 while checking on the display unit 30 whether compaction has been completed. can. The display unit 30 is, for example, a monitor connected to the controller 20 by wire or wirelessly.

FIG. 5 is an example of an image displayed on the display unit 30. As shown in FIG. 5, the display unit 30 displays, in addition to the determination result by the determination unit 24, the ratio calculated by the ratio calculation unit 23 and the reference value for determination used by the determination unit 24. . Therefore, the operator can operate the compaction device 1 while checking the progress of compaction work on the display unit 30. Therefore, compaction work can be performed efficiently.

The photographing unit 10 photographs the surface of the concrete material multiple times at intervals. The controller 20 specifies a changed area from the images taken at each time by the imaging unit 10 and calculates the changed area ratio at each time. The display unit 30 sequentially displays the change area ratio at each time. Therefore, the operator can check the temporal change in the change area ratio on the display unit 30. Therefore, the compaction device 1 can be operated while predicting the time when compaction will be completed, and compaction work can be performed more efficiently.

Instead of sequentially displaying the changing area ratio at each time, the display unit 30 may display a graph showing changes over time in the changing area ratio, with the horizontal axis being time and the vertical axis being the changing area ratio. .

Furthermore, the display section 30 displays an image of the surface of the concrete material photographed by the photographing section 10 (see FIG. 1). Therefore, the worker can check the condition of the surface of the concrete material not only by directly looking at the surface of the concrete material but also by looking at the display unit 30.

Next, a compaction state determination method will be described with reference to FIG. 3.

In the compaction state determination method, first, the surface of the concrete material is photographed using the photographing unit 10 to obtain image information (photographing step). Next, the information of the image acquired in the photographing step is analyzed using the controller 20 (analysis step).

In the analysis step, brightness values or grayscale values between mutually adjacent pixels in a predetermined region of the image photographed in the photographing step are compared. When the brightness value or grayscale value of a pixel changes by more than a predetermined threshold value, the pixel is identified as a change area, and if the brightness value or grayscale value of the pixel does not change by more than a predetermined threshold value, the pixel is identified as a change area. Identify as unchanged area. Next, the ratio of the changed area to the predetermined area is calculated. Next, if the calculated ratio exceeds a predetermined standard value, it is determined that compaction has not been completed, and if the calculated ratio is less than the predetermined standard value, It is determined that compaction has been completed.

With the above steps, the determination of the compaction state is completed.

According to the above embodiment, the following effects are achieved.

In the compaction state determination device 100 and the compaction state determination method, a change area in which the brightness value or the gray value changes by a predetermined threshold value or more is identified from the photographed image of the surface of the concrete material. Therefore, the changing region in the image corresponds to a place where the brightness and shade change on the surface of the concrete material. Therefore, by using the ratio of the change area, the surface condition of the concrete material can be grasped without relying on the senses of the worker, and the compaction state can be appropriately determined.

Further, the display unit 30 sequentially displays the change area ratio at each time. Therefore, the operator can check the temporal change in the change area ratio on the display unit 30. Therefore, the compaction device 1 can be operated while predicting the time when compaction will be completed, and compaction work can be performed more efficiently.

Although the embodiments of the present invention have been described above, the above embodiments merely show a part of the application examples of the present invention, and are not intended to limit the technical scope of the present invention to the specific configurations of the above embodiments. do not have.

In the above embodiment, the case where the compaction work is performed using the vibrator 7 has been described, but the present invention is also applicable to the case where the compaction work is performed using the vibrating roller. Further, the present invention is also applicable to cases where the vibrator 7 is manually inserted into concrete material to perform compaction work.

Light may be reflected on the surface of the paste-like material, resulting in uneven reflection in brightness and darkness. In this case, the controller 20 may erroneously identify the reflection unevenness as a change area. In order to improve the accuracy of specifying the changed area, the changed area may be specified based on the brightness in addition to the brightness value or the gray value. Specifically, areas with high brightness can be presumed to be areas where the surface of the paste-like material is spreading and uneven reflection is occurring, so areas with brightness above a predetermined value are excluded and brightness and darkness are calculated. A pixel whose value or gray value changes by more than a predetermined threshold is identified as a changed area. Thereby, it is possible to prevent the reflection unevenness from being erroneously identified as a changed area, and it is possible to improve the accuracy of identifying the changed area.

100...Compaction state determination device 10...Photographing section 20...Controller 30...Display section

Claims (3)

A compaction state determination device for determining the compaction state of concrete material,
a photographing unit that photographs the surface of the concrete material and acquires image information;
a controller that analyzes information on the image acquired by the imaging unit,
The controller compares brightness values or grayscale values between adjacent pixels in a predetermined area of the image, and identifies pixels whose brightness values or grayscale values change by a predetermined threshold or more between the adjacent pixels as a changed area. and determining the compaction state of the concrete material based on the ratio of the changed area to the predetermined area.
Compaction state determination device. further comprising a display section that displays the ratio,
The photographing unit photographs the surface of the concrete material at a first time and a second time to acquire information on the image,
The controller specifies the changed area from the image at the first time and calculates the ratio at the first time, and also specifies the changed area from the image at the second time and calculates the changed area from the image at the second time. calculating the ratio at a second time;
The display unit displays the ratio at the first time and the ratio at the second time.
The compaction state determination device according to claim 1. A compaction state determination method for determining the compaction state of concrete material, the method comprising:
a photographing step of photographing the surface of the concrete material and acquiring image information;
an analysis step of analyzing information of the image acquired in the photographing step,
In the analysis step,
Comparing brightness values or grayscale values between mutually adjacent pixels in a predetermined area of the image,
Identifying a pixel in which the brightness value or grayscale value changes by more than a predetermined threshold value between the adjacent pixels as a change area,
determining the compaction state of the concrete material based on the ratio of the changed area to the predetermined area;
Method for determining compaction status.

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