기후변화에 따른 자연재해의 증가하고 있다. 이에 자연재해에 의한 토목구조물의 피해 및 붕괴를 예방하기 위하여 처짐 및 균열을 지속적인 관리가 필요하다. 이에 효과적인 구조물 관리를 위해 광학 이미지 기술이 유지관리 기술에 적용되고 있 다. 하지만 광학이미지 기술은 촬영에 따른 주변 조건의 영향이 크며, 그 때문에 촬영조건에 대한 검증이 필요하다. 이를 위해 본 논문에서 촬영조건으로 자연광, 촬영매수, 촬영거리를 따른 수직변위 추정값의 정확도에 대해 검증하였다. 실험을 통 해 확인한 결과 자연광이 수직변위를 추정하는데 자연광이 가장 큰 영향을 미치는 것을 확인할 수 있었고, 촬영거리 또한 수직변위를 검토하는데 주요한 영향을 미치는 것을 확인할 수 있었다. 본 결과를 통해서 외부환경에서 촬영하는데 활용하여 변위 추정 시 발생하는 오차를 최소화할 수 있으며, 이러한 과정을 통해 구조물 유지관리에 적용할 수 있다.

This study developed the pressure measurement monitoring system named VIP-2000 for monitoring a pressure of ullage space in cargo tank. VIP-2000 is designed in compliance with IMO(international maritime organization) SOLAS 74, Chap. II-2 Req. 59. IMO is providing the establishment of a pressure measurement equipment for secure the stability from vacuum or the overpressure that caused by in breakdown of the P/V valve. VIP-2000 operates the early warning of the visible and audibility in dangerous situation of cargo tank. In order to evaluate the performance of VIP-2000, the pressure measurement experiments have been conducted.

The failure behaviours of unidirectional pultruded carbon fiber reinforced polymer (CFRP) composites were monitored by the electrical resistance measurement during tensile loading, three-point-bending, interlaminar shear loading. The tensile failure behaviour of carbon fiber tows was also investigated by the electrical resistance measurement. Infrared thermography non-destructive evaluation was performed in real time during tensile test of CFRP composites to validate the change of microdamage in the materials. Experiment results demonstrated that the CFRP composites and carbon fiber tows were damaged by different damage mechinsms during tensile loading, for the CFRP composites, mainly being in the forms of matrix damage and the debonding between matrix and fibers, while for the carbon fiber tows, mainly being in the forms of fiber fracture. The correlation between the infrared thermographs and the change in the electrical resistance could be regarded as an evidence of the damage mechanisms of the CFRP composites. During three-point-bending loading, the main damage forms were the simultaneity fracture of matrix and fibers firstly, then matrix cracking and the debonding between matrix and fiber were carried out. This results can be shown in Fig. 9(a) and (b). During interlaminar shear loading, the change in the electrical resistance was related to the damage degree of interlaminar structure. Electrical resistance measurement was more sensitive to the damage behaviour of the CFRP composites than the stress/time curve.

The motivation of this paper is to identify the variation of stress filed in multi-strand tendon anchorage system using electromechanical impedance measurement. To achieve the objective, the following approaches are implemented. Firstly, stress variation in multi-strand anchorage system due to strand breakage is analyzed to determine the location of impedance acquisition. Secondly, a piezoelectric-based interface technique is designed to localize the damage strand. Lastly, the conceptual design of the PZT-interface is preliminarily verified by an experimental test. Impedance signatures obtained from PZT-interface are quantified by using RMSD index (root-mean-square-deviation). The result shows that the PZT-interface technique is promisingly to identify damage strands.

A video-based non-contact remote displacement measurement system is proposed and developed. The system captures images of the structure and analyzes the image to determine the displacement. Multi-thread computing and adaptive region of interest method is implemented in the system to compute the displacement in real-time. Field test on a real structure has been carried out to evaluate the performance and verify the reliability of the system.

Recently, the event of slope failure has been occurring frequently due to rapid climate changes and broad development of infrastructures, and the research for establishment of monitoring and prevention system has been an attentive issue. The major influence factors of slope failure mechanism can be considered moisture and temperature in soil, and the slope failure can be monitored and predicted through the trend of moisture-temperature change. Therefore, the combined sensing technology for the continuous measurement of moisture-temperature with different soil depths is needed for the slope monitoring system. The various independent sensors for each item (i.e. temperature and moisture respectively) have been developed, however, the research for development of combined sensing system has been hardly carried out. In this study, the high-fidelity sensor combing temperature-moisture measurement by using the minimized current consuming temperature circuit and the microwave emission moisture sensor is developed and applied on the slope failure monitoring system. The feasibility of developed monitoring system is verified by various experimental approaches such as standard performance test, mockup test and long-term field test. As a result, the developed temperature-moisture combined measurement system is verified to be measuring and monitoring the temperature and moisture in soil accurately.

현재 공용중인 대부분의 시설물들은 다양한 센서로 구성된 계측시스템을 구축하고 있으며, 시스템에서 계측된 응답 데이터 분석을 통해구조물의 건전성을 평가하고 있다. 건전성 평가 과정에서 적용하는 계측데이터의 계측관리기준은 일반적으로 공용 초기에 설정된 것으로,시공회사 또는 설계회사 소속의 전문가들이 설계기준을 바탕으로 혹은 구조해석을 통해 설정하고 있다. 하지만 실 계측데이터에 적용하기위해서는 이와 같이 설정되는 계측관리기준의 검증이 필요하며, 일부 연구자들은 교량의 관리를 위해 실 계측데이터에 계측관리기준을 적용하여 타당성을 검증하는 연구를 수행하고 있다. 본 논문에서는 통계적 접근방법을 활용하여 기설정된 계측관리기준을 검토하고, 체계적인 계측관리기준 재설정 방안을 제시하였다. 또한 구조물의 실 계측 데이터에 적용하여 그 타당성을 검증하였다.

To manage the data measured from Honam high-speed railroad(HSR) infrastructure(environmental noise reduction structures, track structures, catenary system), we are trying to establish an integrated database through analysis of the developed infrastructure technologies and standards, construction of prototypes on the fields and evaluation of infrastructure performance according to the increment of train speed. In this paper, integrated monitoring center for management of measured data is suggested.

The FBG sensor responses simultaneously to changes in thermal strain as well as elastic strain. Thus the total strain measured from a single FBG sensor shall be corrected to obtain the elastic strain by removing the temperature effect. This paper addresses how the temperature effect can be removed when the FBG sensor is encapsulated in a 7-wire steel strand. For this purpose, fundamental properties of the FBG sensor are identified through tests using a controlled temperature chamber. Then field measurements on a UHPC pi girder with the size of 11.0 m long, 5.0 m wide, and 0.6 m high have been conducted for about one year, and the prestressing force is estimated using the raw data from the FBG sensor and by applying temperature correction technique proposed in this study. Estimated results indicate that the proposed correction technique is executable for extracting the elastic strain from monitoring data using the FBG sensor in civil infrastructures.

Test-bed was constructed in Honam High-speed railway due to evaluate the suitable infrastructure for operation of 400km/h level speed. To evaluate performance of roadbed in test-bed, several sensors installed in the standard roadbed, soft ground, transition zone as bridge and earthwork. In contrast to existing long-term monitoring, system developed was designed and builted on site to log-time operation automatically. Therefore, the measured data collected monitoring system and analysis results can be databased continuously from construction to operation of railway for study design criteria about long-term behavior of roadbed.

In this study, the measurement items for establishing the structural health monitoring for super tall buildings were proposed. The items were classified in level of structure, as a structure level and a member level. The external forces and internal responses are measured at each level to monitor the behavior of structure in real time.

This study introduces a novel approach to the differentiation of two phenomena, Asian Dust and haze, which are extremely difficult to distinguish based solely on comparisons of PM10 concentration, through use of the Optical Particle Counter (OPC), which simultaneously generates PM10, PM2.5 and PM1.0 concentration. In the case of Asian Dust, PM10 concentration rose to the exclusion of PM2.5 and PM1.0 concentration. The relative ratios of PM2.5 and PM1.0 concentration versus PM10 concentration were below 40%, which is consistent with the conclusion that Asian Dust, as a prime example of the coarse-particle phenomenon, only impacts PM10 concentration, not PM2.5 and PM1.0 concentration. In contrast, PM10, PM2.5 and PM1.0 concentration simultaneously increased with haze. The relative ratios of PM2.5 and PM1.0 concentration versus PM10 concentration were generally above 70%. In this case, PM1.0 concentration varies because a haze event consists of secondary aerosol in the fine-mode, and the relative ratios of PM10 and PM2.5 concentration remain intact as these values already subsume PM1.0 concentration. The sequential shift of the peaks in PM10, PM2.5 and PM1.0 concentrations also serve to individually track the transport of coarse-mode versus fine-mode aerosols. The distinction in the relative ratios of PM2.5 and PM1.0 concentration versus PM10 concentration in an Asian Dust versus a haze event, when collected on a national or global scale using OPC monitoring networks, provides realistic information on outbreaks and transport of Asian Dust and haze.

In this study trying to develop a monitoring system for temperature and humidity measurement of quality control methods suitable for curing concrete nuclear power plant structures. This experiment is divided part of data logger, sensors, control program in a accordance with standar of quality control Nuclear power plant hot weather/the middle of summer. This measuring method is expected to development quality control nuclear power plant

본 논문에서는 MEMS 센서와 블루투스 무선 통신 모듈을 이용하여 교량 모니터링을 위한 무선 계측 시스템 개발에 대한 연구를 수행하였다. 이를 위하여 MEMS 센서의 가속도 측정 범위 및 주파수 응답 범위 성능을 검증하기 위한 실험을 수행하여 교량 계측에 적합성 여부를 판단하였다. 실험 결과, 고성능의 압전형 가속도 센서에 비하여 동적 범위와 측정 주파수 범위의 성능은 낮으나 30Hz 미만의 저주파수 대역 측정에는 무리가 없을 것으로 판단한다. 그리고 최대 통신 거리 측정 결과, 280m정도의 성능을 가지고 있음을 확인하였다. 마지막으로 개발된 무선 가속도 센서 시스템을 공용중인 교량에 설치한 후, 교통하중에 의한 진동데이터를 획득하여 교량의 동특성을 실시간 분석하였다. 분석결과는 대상교량의 FE 해석결과와 비교를 통하여 무선 가속도 센서 시스템의 성능을 평가하였다. 실험 결과, MEMS 센서와 블루투스 무선 통신 모듈을 이용하여 개발한 무선 가속도 센서는 교량과 같은 저주파수 진동특성을 갖는 건설구조물의 계측에 효과적으로 사용할 수 잇을 것으로 판단된다.

도로포장의 유지관리를 위해서는 운전자가 직접적으로 느끼게 되는 평탄성에 대한 관리가 중요하며 이를 위해서는 지속적인 평탄성 측정 및 모니터링이 중요하다. 우리나라 일반국도의 경우 자동화된 포장조사장비를 이용하여 포장상태를 측정하여 관리하고 있는데, 이러한 자동화된 조사장비들은 매우 고가여서 보유대수가 부족하므로 지자체 등에서는 운영하기가 어려운 상황이다. 또한 평탄성은 도로 등급이나 사용 목적 및 용도 등에 따라 정밀도를 달리하여 측정하고 운영할 수 있어야 하지만 아직 이러한 적용은 하지 못하고 있는 상황이다. 본 연구에서는 기존에 개발된 저가의 장비를 이용한 평탄성 측정의 가능성을 확인하였다. 먼저 운행차량의 중량측정을 위한 운행차 하중측정 장치에 대해 살펴보고, 이 장치에서 사용되는 가속도계를 이용한 종방향 이동거리에 대한 도로구배의 측정이 가능함을 확인하였다. 도로구배 측정 결과를 θ값을 이용하여 고도 데이터로 변환하면 노면의 프로파일 형상을 얻을 수 있으며 이를 활용하면 그 구간에 대한 평탄성 측정이 가능할 것으로 파악되었다.

국내산지사면의 토양수분 시공간적 분포상황을 파악하기 위한 토양수분 측정법이 개발되었다. 대상유역을 정밀측정하여 수치고도모형을 구성한 다음 흐름분배 알고리즘을 적용하고 공간적 변화의 대표성을 최대화하기 위한 측정체계를 구축하였다. 토양수분이 강우-유출형성과정에 기여하는 기작을 표현하는 유도과정도 전개되었다. 측정은 설마천 유역의 법륜사 우측사면에서 수행되었다. 다중 측정망의 운영을 통하여 시공간적으로 변화하는 토양수분 자료를 획득하였다. 습한 조건에서 토