논문 상세보기
pp.51-60
PURPOSES : In this study, an existing speed-controlled Marshall stability tester was systemized as an Internet of Things(IoT) system. The Marshall stability test data were transmitted to the cloud in real-time, and an IoT optional-controlled board capable of additional load and displacement control was proposed.
METHODS : The IoT systemization was built based on an improvement of an IoT height measuring system, the re-verification of standard samples for comparative analysis, and the development of a wireless IG-IoT board. The developed wireless Induk-GeoTS(IG)-IoT board was compared with existing commercial data logger using displacement- and load- calibration equipment. After the conformity of the developed wireless IoT board was established, a urethane standard sample was reproduced and verified using the recipe presented in a previous study to conduct a round-robin test. In addition, the adequacy of the speed, load, and displacement control tests for the optional-controlled characteristics was verified. the round-robin test for the Marshall stability and deformation strength and the comparative test of indirect tensile strength with the existing Marshall tester were performed using the re-verified standard sample.
RESULTS : The improved two-point IoT height measurement system reduced the average relative error by 2.11% relative to the one-point measurement. From the re-verification results of the regenerated urethane standard sample, it was suitable with relative error of 3.65% in the loading elastic modulus and 4.07% in the unloading elastic modulus, compared to the existing standard sample. From the comparative analysis of the developed wireless IG-IoT board and existing commercial data logger, it was confirmed that the wireless IoT board could be reliably used, based on the average relative error of the wireless IoT board, 0.64% and that of the data logger, 3.79% in terms of the displacement(flow value) and an average relative error of 0.78% for the wireless IoT board and 0.79% for the data logger in terms of the load(stability). By analyzing the optional-controlled characteristics, it was found that the Marshall stability speed control conditions were satisfied based on the error results, with an average relative value of 2.96% under deformation strength test condition of 30mm/min, 3.23% under the indirect tensile strength test condition of 50mm/min, and 2.6% under the Marshall stability test condition of 50.8mm/min. It was also found that proper control characteristics were obtained, with an average relative error of 0.72% within the experimental load range in the load control conditions, and an average relative error of 2.4% in the experimental displacement range in the displacement control conditions. The results from the round-robin Marshall stability and deformation strength testing to verify the applicability of the IoT optional-controlled board show that the data were reliable based on the 3σ quality control method. In addition, by comparing the results of the indirect tensile strength tests, the usability of the wireless IG-IoT board was verified, with an average relative error of 0.96%. CONCLUSIONS : The IoT height measuring system was improved, and a wireless IG-IoT board that can transmit test data to a cloud platform was developed. The usability of the developed wireless IoT board was verified by round-robin testing using a re-verified urethane specimen. The IG-IoT optional-controlled board extends the verified wireless IG-IoT board, it was developed and validated for not only the existing speed control, but also for load, and displacement control.
1. 서론
2. 마샬안정도 시험기의 IoT 시스템 구축
2.1. IoT 높이측정장비 개선
2.2. 표준시료의 사용성 검증
2.3. IoT 시스템 구축을 위한 IoT 보드의 필요성
2.4. 속도제어형 무선 IG-IoT 보드 시작품 개발
3. 개발된 속도제어형 무선 IG-IoT 보드 검증
3.1. 변위(흐름치) 검증시험
3.2. 하중(마샬안정도) 검증시험
4. 선택제어형 무선 IoT보드 개발
4.1. 하중제어와 변위제어의 필요성
4.2. 속도 제어 시험
4.3. 하중 제어 시험
4.4. 변위 제어 시험
5. 검증된 표준시료를 통한 라운드 로빈 시험
5.1. 마샬안정도 라운드 로빈 시험 결과
5.2. 변형강도 라운드 로빈 시험 결과
5.3. 기존 시험기와 간접인장강도 비교 시험
6. 결론
REFERENCES
