PURPOSES : The purpose of this study is to analyze the crack and vertical behaviors of a continuously reinforced concrete pavement (CRCP) under three different steel ratios (0.6%, 0.7%, and 0.8%) using field measurement data acquired from isolated concrete slabs with transverse cracks. METHODS : Using an LVDT and a crack gauge, CRCP behavior data are acquired by segmenting a concrete slab into multiple sections based on the similarity in the longitudinal steel ratio of each section. To examine the vertical behavior of CRCP based on longitudinal steel ratios, three field experiments are conducted in February, May, and September three years after project completion. The minimum and maximum ambient temperature data for each section are acquired during the experiments. Using the data acquired, the vertical and crack behaviors of CRCP with 0.6% of longitudinal steel ratios are analyzed. In addition, the effect of the steel ratio on the vertical behavior as well as seasonal vertical behaviors are examined. RESULTS : Analysis of the vertical behavior of concrete slabs with a 0.6% steel ratio shows that the minimum vertical displacement occurred at the center of the slab, whereas a significant vertical displacement is detected on the edges of the slab. Based on examining vertical displacements formed along the direction of transverse cracks, it is observed that the vertical behavior is prominent around the shoulders, whereas similar vertical behaviors are observed at the center and joints of the slab. Furthermore, it is discovered that the minimum crack occurred at the center of the transverse cracks, whereas the maximum crack occurred on the shoulders and joints. Furthermore, it appears that the daily displacements of the vertical behavior at the center of the slab constitute approximately one-half of the daily displacements on the joints. Based on the results of vertical behavior as a function of the longitudinal steel ratios, it is discovered that steel ratios of 0.7% and 0.8% yield the most prominent vertical behaviors around the edge of the shoulder in the winter, spring, and fall seasons. The seasonal deviations of the vertical behaviors based on the measuring positions of the longitudinal steel ratios appear less significant at the center of the slab than those on the shoulder. In particular, for the slab with a steel ratio of 0.8%, subtle vertical behaviors are observed at the center. It is discovered that the seasonal deviation of the vertical behavior measurements varying by the measuring locations of the steel ratios appears less significant at the center of the slab than at the shoulder, and that it decreases with the steel ratio. CONCLUSIONS : CRCP generates cracks on the slab; however, they are managed by rebars in the CRCP. This study reveals that the major vertical and crack behaviors of CRCP occur around the shoulders than at the center of the CRCP slab. Therefore, new methods for managing cracks on the CRCP shoulder should be developed to improve the performance of CRCP. It is hoped that the results presented herein will be useful for the advanced analysis of CRCP behaviors.

전단파속도가 1,050m/sec 이하인 경우의 기초지반에 대한 내진해석에서는 지반-구조물 상호작용해석이 반드시 수행되어야 하며, 이러한 기초지반에서는 강지진동 작용시 지반의 비선형성이 현저하게 나타나므로 내진해석시 지반의 비선형성은 필수적으로 고려되어야 한다. 따라서, 본 연구에서는 입력지진동에 따른 지반의 비선형 거동을 평가하기 위한 방법으로서 기존의 수치해석적인 방법에 비하여 평가절차가 단순하고 신뢰성이 높은 Downhole 지진계측자료에 의한 평가방법을 제안하였다. 대만 화련부지를 대상으로 본 연구에서 제안한 지반의 비선형성 평가방법에 대한 신뢰성을 검증한 결과, 기존의 SHAKE프로그램에 의한 평가결과 및 지진응답 계측결과에 잘 일치하는 높은 수준의 정확성을 보임으로써 그 신뢰성 및 가용성을 확인할 수 있었다.

최근 한반도 지진 발생 회수, 규모 증대 및 전과 다른 내륙에서 발생 등, 외적으로는 지진 하중의 위험성이 증가하고 있으며, 이와 더불어, 국내 사회기반시설물의 노후화에 따른 내적인 취약성 역시 가중 되고 있다. 지진 발생 시 긴급 대처와 유연한 대책 마련을 위한 과학적이고 합리적인 안전성 평가 기술은 시설물 자체 손상을 넘어 붕괴 시 많은 2차 피해를 야기할 수 있는 대표적인 사회기반시설인 댐 저수지 및 교량에 있어 매우 미진한 상태이다. 또한, 중요시설물의 관리 주체는 시설물별 가속도 관측을 수행하고 있으나, 설치된 장비의 성능 및 비용을 고려시 상대적 활용도가 매우 낮은 실정으로, 이러한 활용도를 제고하는 기술개발이 요구되는 상항이다.

This paper is a study on the development of a data analysis platform that constitutes a part of the development task of the constant monitoring system that can prepare against the earthquake disaster by using the regular measurement data of the old school buildings. The data analysis platform is composed of database management software that manages the metrology data acquired by using the instrument and data management software that analyzes the metrology data, analysis tools that can analyze the metrology data in various ways, A data analysis platform can be used to assess the safety of the school building and evaluate the seismic safety of the old school building to build a system for earthquake disaster.

Earthquake safety assessment software of the cable-stayed bridge using the seismic acceleration measurement date was developed. Various safety assessment indices for evaluation structural safety and serviceability of bridges are discussed. A systematic approach is proposed to process the raw data for generating appropriate safety assessment indicators. The software for structural state evaluation includes (i) format conversion of raw data, (ii) noise filtering, (iii) generation of assessment index, (iv) state evaluation. Determination of the limit state included in the condition evaluation step is discussed and an example of the graphic user interface of the software is shown.

Earthquake safety assessment software of the cable-stayed bridge using the seismic acceleration measurement date was developed. Various safety assessment indices for evaluation structural safety and serviceability of bridges are discussed. A systematic approach is proposed to process the raw data for generating appropriate safety assessment indicators. The software for structural state evaluation includes (i) format conversion of raw data, (ii) noise filtering, (iii) generation of assessment index, (iv) state evaluation. Determination of the limit state included in the condition evaluation step is discussed and an example of the graphic user interface of the software is shown.

This study focused on whether the large-scale expansion joints of the Diamond Bridge, a suspension bridge, is being appropriately and efficiently utilized during maintenance period. In this study, a linear regression model was developed by analyzing long-term monitoring data from the bridge, considering the bridge design standards in Korea and building-related literatures. Then, the reliability of the model was verified through a theoretical review on the relationship between temperature change and expansion joint displacement. The expansion joint displacements of the bridge showed a regular time series graph with temperature change. A linear regression analysis indicated that the slope of the graph was very similar to the displacement of steel due to linear expansion coefficient, with a high determination coefficient (R2=0.979), meaning that the actual behavior of the bridge conforms to the theory. Considering the expansion joint specification of the bridge and existing external loads, actual expansion joint displacement was only 8.5 percent of its specification, so the specification can be adjusted in order that actual expansion joint displacement can be up to 21.6 percent of its specification. In this case, expansion joint cost can be reduced as much as 78.4 percent of its original cost.

대다수의 흙막이 공사 계측현장에서 적용하고 있는 절대치 관리방법은 관리기준치와 계측결과를 절대 비교함으로서 공사현장의 안전성을 평가하는 기법이다. 따라서, 안전성 평가의 판단기준이 되는 관리기준치는 평가결과에 직접적으로 영향을 미치게 된다. 즉 아무리 최 적의 계측시스템이 적용된 현장이라고 하더라도 관리기준치가 타당하지 않으면, 공사현장의 안전성을 정확히 판단할 수 없으므로 관리기준치 의 선정은 매우 중요하다. 그러나 실질적으로 현장 기술자 등은 기존 절대치관리기준치에 대한 신뢰성이 매우 낮으며 관리기준치의 수정보완 의 필요성을 인식하고 있다. 이에 본 연구에서는 계측관리기준치의 수정보완 필요성에 대한 조사결과를 바탕으로 하여 흙막이 구조물의 거동 중 가장 기본이 되며 중요한 흙막이 벽체의 변위에 대한 계측결과를 토대로 확률론적 이론에 의해 관리기준치를 보다 적절하게 설정하여 적용 하는 연구를 수행하였다. 본 연구에서는 계측관리기법 중 시공 전에 설정된 관리기준치와 시공 시 측정된 설측치를 비교 검토하여 그 시점에서 공사의 안전성을 확인하는 방법인 절대치관리방법을 적용하여 관리기준치를 수정하였다.

In this study, among the reliability assessment method for measured data of dam instrumentation, time series analysis and behavior analysis were introduced and the reliability assessment cases for seepag weir, pore-pressure meter, concrete stress meter and joint meter were presented.

This paper developed analysis model with measured data and geometric nonlinearity for more precise evaluation of structure behavior of suspension bridge. This analysis model helps to make plan and evaluate of structure behavior for accidents such as traffic, typhoon and earthquake. Also, this helps to make maintenance and management plan for structure.

Structural dynamic characteristics are obtained by analysing responses of seismic acceleration measuring system obligatorily installed in public structures. Emergency structural safety estimation using these data supports decision making of a structure manager when an earthquake or a strong vibration happens. And proper standards for structural safety are suggested by cumulative statistical analysis. For these reasons, it is necessary that comprehensive analysis and management system indicates analysis results based on GIS(Geographic Information System). This system is developed with comprehensive analysis algorithms and data processing procedures. Various information through the system is served for structural safety management.

One of the most important processes to accurately predict structural responses is to evaluate accurate structural dynamic properties using finite element (FE) models. The analyzed structural dynamic properties usually show considerable discrepancies with the measured ones because structural details are commonly simplified in the FE models. To identify such discrepancies, FE models of them have been calibrated using the measured dynamic properties in previous researches. In this study, dynamic properties were measured for a historic cathedral and the FE model of it was calibrated using the measured results as a reference. Finally, a procedure of the FE model construction for masonry cathedral were tentatively proposed.

Acoustic Doppler Current Profilers (ADCPs) are increasingly popular in the river research and management communities being primarily used for estimation of stream flows. ADCPs capabilities, however, entail additional features that are not fully explored, such as morphological representation of river or reservoir bed based upon multi-beam depth measurements. In addition to flow velocity, ADCP measurements include river bathymetry information through the depth measurements acquired in individual 4 or 5 beams with a given oblique angle. Such sounding capability indicates that multi-beam ADCPs can be utilized as an efficient depth-sounder to be more capable than the conventional single-beam eco-sounders. The paper introduces the post-processing algorithms required to deal with raw ADCP bathymetry measurements including the following aspects: a) correcting the individual beam depths for tilt (pitch and roll); b) filtering outliers using SMART filters; d) transforming the corrected depths into geographical coordinates by UTM conversion; and, e) tag the beam detecting locations with the concurrent GPS information; f) spatial representation in a GIS package. The developed algorithms are applied for the ADCP bathymetric dataset acquired from Han-Cheon in Jeju Island to validate themselves applicability.

200m 이하의 아치 교량에서 동적 내풍 안정성은 일반적으로 일본의 Wind Resistant Design Manual for Highway Bridges에 따라 검토된다. 또한 내풍 안정성 검토는 모드 형상에 관계없이 1차 연직 진동수를 적용한다. 일본의 매뉴얼에 따라 설계된 경간장 183m의 닐슨 아치 교량에서 예상치 못한 와류 진동이 발생하였으며 이는 태풍시 교량의 모니터링 시스템에 의해 계측되었다. 본 논문에서는 태풍 발생시에 계측된 풍속, 풍향, 진동 변위와 가속도를 기반으로 닐슨 아치교량의 와류진동 특성을 분석하였다. 분석 결과 1차 연직 진동 모드가 역대칭 형상이고 2차 연직 진동 모드가 대칭 형상인 닐슨 아치교의 경우 와류 진동이 2차 연직 모드에서 지배적이다. 따라서 본 논문에서는 2차 연직 진동 모드가 대칭 형상인 닐슨 아치교의 내풍 안정성 평가시에는 1차 보다 2차 연직 진동 모드가 중요한 설계 요소임을 제시하였다.

본 연구에서는 미계측 강수자료를 생성하여 공간 해석함으로써 제주도의 정확한 수문총량을 산정하였다. 미계측 강수자료는 본 연구에서 제시된 수정된 다중회귀선형 모형으로 생성하였으며 공간강수량은 PRISM을 적용하여 구하였다. 수정된 다중선형회귀 모형에 의한 미계측 강수자료의 추정 값들은 기존의 강수 패턴과 유사한 양상을 나타내어 모형의 정확도가 우수한 것으로 나타났으며, 공간강수량의 해석 결과는 Case 1(원자료)과 Case 2(미계측 강수자료를 보완한 자료)의 연평균 강수량이 약 1.5%의 미미한 차이를 나타내었으나 고도별 연평균 강수량 차이는 최대 37.4%가 증가하는 것으로 산정되었다. 따라서 본 연구에서 제안한 미계측 관측 자료 생성방법은 현재 관측소의 밀도가 낮은 곳과 국지적으로 강수량의 변화가 큰 곳에서의 수문총량의 산정시 유용할 것으로 판단된다.