Kashima
Achieved quality control of all CSG materials while reducing testing personnel by 90% at Naruse Dam!
Calculate the total amount of surface water in real time from the particle size distribution and moisture content of the material ……
Kajima (President: Hiromasa Amano) has developed a system (hereinafter referred to as this system) that manages the total amount of water on the surface of materials used in dam construction, etc., and has realized labor savings in material quality control work. This system combines the “AI image particle size monitoring (R) system” developed by our company in 2021 and total moisture content management technology using a near-infrared moisture meter. This system was recently introduced on a trial basis to the manufacturing of CSG*1 for the Naruse Dam body pouring work ordered by the Ministry of Land, Infrastructure, Transport and Tourism, which our joint venture is constructing in Akita Prefecture, and is monitoring changes in the particle size distribution and moisture content of CSG materials*2. I did it. As a result, we confirmed that compared to testing using conventional methods, we were able to reduce the number of personnel involved in testing by approximately 90% while ensuring the same measurement accuracy, and we were able to seamlessly control the quality of the total amount of CSG material supplied. .
This demonstrated the effectiveness of this system, and it was adopted for quality control of CSG materials during the dam construction. *1 Cemented Sand and Gravel: Material made by mixing locally generated materials (stones and gravel), cement, and water.※2 Locally generated materials (stones and gravel) that have been selected to have a particle size below a specified maximum particle size. Equivalent to concrete aggregate
[Image 1: https://prtimes.jp/i/116603/71/resize/d116603-71-ce2c675b77526e7f1353-0.jpg&s3=116603-71-6a9d626375da679b88df585e4e18b2fe-1949×588.jpg] “AI image particle size monitoring system” that manages the entire particle size distribution
[Image 2: https://prtimes.jp/i/116603/71/resize/d116603-71-67f4946c6935af77368b-1.jpg&s3=116603-71-ef2f19e108f892aa34e38e83ecbcbadc-258×215.jpg] Monitoring of changes in particle size distribution and moisture content Development background
For quality control of materials in the construction of trapezoidal CSG dams such as the Naruse Dam, sampling tests are conducted once every 1 to 2 hours to check the particle size and moisture content of the supplied CSG materials to ensure that the CSG materials are within the specified specifications. You need to make sure that. However, these tasks, which often span day and night, require a considerable number of people and time, so reducing the burden on testers has been an issue. Therefore, Kajima is proceeding with technology development with the aim of realizing a system that can save labor in material quality control work and seamlessly control the quality of all materials, and has recently introduced this system on a trial basis to CSG manufacturing for the dam construction. , confirmed its
effectiveness. The “Image Granularity Monitoring (R) System” on which this system is based was first introduced at Tobetsu Dam (Ishikari District, Hokkaido) in 2010, and has since been used in multiple dam construction projects.
Overview of total volume management using this system
1. “AI image particle size monitoring system” that manages the entire particle size distribution of materials The “AI image particle size monitoring system” measures the particle size distribution of the target material by identifying and analyzing the contours of soil particles from images of ground materials It is a system to do. AI, which has learned the shape and color of soil particles in advance, recognizes the soil particles in the image. The particle size distribution of the target material is determined based on the size (number of pixels) of each soil particle on the image. With the introduction of AI, there is no longer a need for equipment to improve soil particle recognition accuracy, which was previously required. During the Naruse Dam construction, a camera was installed on the conveyor belt to continuously take still images of soil particles and analyze them.
[Image 3: https://prtimes.jp/i/116603/71/resize/d116603-71-918bc29a300d0cdaf461-2.jpg&s3=116603-71-1ebc89315f386d2f4b6923d28fce60bc-881×680.jpg] Camera installation status on the belt conveyor
Furthermore, since soil particles can be photographed and analyzed using smart devices, the particle size distribution of target materials can now be easily measured anytime and anywhere, expanding the range of implementation of the “AI Image Particle Size Monitoring System.”
[Image 4: https://prtimes.jp/i/116603/71/resize/d116603-71-17cf6d6ad6fb1e12ec04-3.jpg&s3=116603-71-6c4ada153981eed2e725a8f3dc71e542-2191×1357.jpg] Portable AI image granularity monitoring system
2. “Near-infrared moisture meter” that manages the total moisture content of materials. “Near-infrared moisture meter” uses the property of water to strongly absorb infrared rays of a specific wavelength, and measures the degree to which light is absorbed by a material (absorbance). ) is a measuring device that has the technology to calculate the moisture content of the target material. The target material is irradiated with near-infrared rays, the absorbance of its surface is measured, and the results are used to calculate the moisture content of the target material. During the Naruse Dam construction, we installed a near-infrared moisture meter on the conveyor belt, similar to the “AI Image Particle Size Monitoring System,” to achieve continuous measurement and calculation of moisture content.
[Image 5: https://prtimes.jp/i/116603/71/resize/d116603-71-96a64aa043909386ec1f-4.jpg&s3=116603-71-029ed42563e53273e7cd19b9abcea352-933×680.jpg] Installation status of near-infrared moisture meter on belt conveyor Results of introducing this system
During Naruse Dam construction, we installed an “AI image particle size monitoring system” and a near-infrared moisture meter in three systems of CSG manufacturing equipment to monitor changes in the particle size distribution and moisture content of CSG materials. As a result, we confirmed that it is possible to seamlessly control the quality of the entire amount of CSG material that is continuously supplied at an average rate of 300 m3*3/h, while reducing the number of personnel involved in quality control work by approximately 90%. *3 Equivalent to about one cup of a standard elementary school 25m pool (length 25m x width 12m x depth 1.2m)
One of the important indicators for controlling the quality of CSG is the surface water content of CSG materials. This amount of surface water is calculated from the measured particle size distribution and water content. During the same dam construction, we confirmed that the surface water volume of CSG materials calculated from the measurement results using this system had the same measurement accuracy as tests using conventional methods.
[Image 6: https://prtimes.jp/i/116603/71/resize/d116603-71-7c47ce46b7d5a66ac962-5.jpg&s3=116603-71-9f7d722db28f1e17b10262455473b39b-1949×507.jpg] Comparison of surface water amount calculated by this system and conventional method
In response to this, the “AI image granularity monitoring system” was adopted in advance for the dam construction, and actual operation will begin from the end of October 2023. As a result, particle size testing using the conventional method, which used to be carried out once every 1 to 2 hours day and night, can now be carried out once a day, significantly reducing the burden on testers. In addition, it has been decided that technology for controlling total moisture content using a near-infrared moisture meter will be adopted, and once actual operation begins in April 2024, the burden on testers is expected to be reduced, similar to the “AI image particle size monitoring system.” the next deployment
In the future, Kajima will widely deploy this system to construction work other than dams, such as land reclamation work. In addition, by building a system that automatically adjusts the water supply amount based on the surface water amount calculated from the measurement results of this system, we will further save labor in quality control of CSG manufacturing and further promote work style reform at construction sites. We will continue to promote this.
Construction outline
Construction name: Naruse Dam body pouring work (2nd phase)
Construction location: Tsubakigawa, Higashinaruse Village, Ogatsu District, Akita Prefecture Client: Ministry of Land, Infrastructure, Transport and Tourism Tohoku Regional Development Bureau Contractor: Kashima, Maeda, Takenaka Civil Engineering Special Construction Work Joint Corporate construction specifications: Trapezoidal CSG dam, levee height 114.5 m, levee crest length 755 m, levee volume 4.85 million m3, water storage capacity 78.5 million m3 Construction period: June 2023 to December 2026
(reference)
Kajima’s civil engineering technology “Dam” in video
https://www.kajima.co.jp/tech/c_movies/index.html#anc_dam
More details about this release:
https://prtimes.jp/main/html/rd/p/000000071.000116603.html