This paper presents the seismic assessment of the effect of vertical ground motion on the three-story RC building with different geometric configurations considering the vertical-to-horizontal peak ground acceleration (V/H) ratio increases. The effects of a suite of earthquake ground motion records on three-story RC buildings are presented and the results are compared with the case of horizontal only excitation. Interstory drift was considered as a global failure criterion, while the curvature ductility and shear capacity of structural members were monitored to assess failure on a local level. The effect of vertical ground motion on axial force and shear capacity is also investigated.

In this study, the integrated management code of damage information in bridges using the data from unmanned inspection equipment (i.e., drone with hybrid imaging equipment) was proposed. It was found that the integrated management code could be used in developing bridge management system based on 3-dimensional information model of bridge.

In this study, the integrated management code of damage information in bridges using the data from unmanned inspection equipment (i.e., drone with hybrid imaging equipment) was proposed. It was found that the integrated management code could be used in developing bridge management system based on 3-dimensional information model of bridge.

This study was performed to evaluate the cable tension of cable-stayed bridge by using vibration method and Lift-Off Test. As a result, cable tension by the vibration method and Lift-Off Test is most similar.

In this study, measurement temperature in the bridges was compared with temperature proposed by Korean design code. In addition, the structural analysis was performed in order to comparing the stress by measured thermal load and the stress by design thermal load. As a result, the stress that applied measurement temperature was evaluated larger than the stress that applied temperature proposed by Korean design code.

The thermal load must be considered to design cable supported bridges as a variable load. The thermal load recommended by Korean design code might be different to real temperature distribution in the bridges because the thermal load proposed by Korean design code is referred to Eurocode, etc. Therefore this study proposes the temperature distribution of cable supported bridges In Korea based on measurements.

The wind load characteristics are represented by wind speed, wind direction, turbulence intensity, roughness index of terrain, spectral density and so on. In this paper, the wind load characteristics of long span bridges in general national roads are evaluated based on measured data of wind speed and direction.

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.

The static aerodynamic forces are composed of six components. Three components of them such as drag force, lift force and pitching moment are the biggest influence on the structure. These aerodynamic forces are generally evaluated from wind tunnel test or CFD. In this study, drag and lift force coefficients are estimated using relation of actual and analytical displacements. The actual displacements are measured by monitoring system when the bridges were under the typhoon. The analytical displacements due to uniform load are calculated by FEM. Also, the adequacy of estimation method was conformed by comparing the result of this study with that from the wind tunnel test of the similar bridge section.

The corrosion is a main cause of degradation damage in the steel bridges. The evaluation whether the repair or reconstruction would be need or not for the corroded steel member, is based on cross section and quantity of corroded portion. It is considered reasonable that the evaluation will be base on the endurance of the corroded member. In this study, the bending endurance of the I-shaped steel girder with the local corrosion on the lower flange is discussed by using elastic-plastic finite element analyses. That simple way of estimating it is also proposed.

This paper was manufactured for Self-compacting mortar using perlite. This results showed a good estimation that It will be able to examine for fire resistance.

Structural damping includes material damping, friction effects at bearing and expansion joints, friction at bolted joints and mechanical damping by damper. There is not analytical basis for estimating the damping ratios. Structural damping ratios can be estimated by measuring forced vibration amplitude of a certain mode but it is almost impossible to vibrate the actual bridges to a certain mode by force. Therefore, RD technique utilizing a lot of ambient vibration data can be a practical method to estimate damping ratio. In this study, the damping ratio is estimated by analyzing the ambient vibration data of three steel cable stayed bridges.

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.

The impact factor of general road bridges is typically calculated according to Korea Highway Design Code(KHDC) or Design Guidelines For Cable-Supported Bridges in Korea. Above design codes define the impact factor as the function of span length or effective span length. But calculated impadt factors from this function are different to the measured values of long-span bridges such as cable-stayed bridge, suspension bridge. There are several methods to estimate the impact factor of cable supported bridges. In this study, the impact factor of cable-stayed bridges is estimated from dynamic load tests and compared to calculated values from the various design codes.

The damping ratios of the modes as well as the natural frequencis and the mode shapes are required to characterize the modal behavior of structure. The mode shapes and the natural frequencies are determined from analytical methods or measurements accurately. But there is little analytical basis for estimating the damping ratios although they are the most important to determine the amplitude of the vibration. Especially for the cable-stayed bridges the aerodynamic damping ratios determine the amplitude of the response to wind loads. This paper is an attempt to estimate the aerodynamic damping ratios based on measured data and quasi-static theory.

Vortex shedding occurred at relatively low mean wind velocities between 13m/s and 16m/s in the 2nd Jindo grand bridge. To control the vortex shedding Multiple Tuned Mass Damper(MTMD) was installed in the mid span. The control effects of MTMD was verified by assessing the damping ratio before and after installing MTMD. This paper present the evaluation of damping ratio of a cable- stayed bridge based on measuring data through unified remote monitoring system.

The structural stability as well as wind environments were not evaluated until now during maintaining in-service long span bridges unless wind-associated problems occur. Recently, typhoons or strong winds occur frequently because of global warming and climate changes so it is necessary to evaluate the wind stability of in-service bridges considering wind environment based on the field measurement. This study provides some basic information for wind environments of Dolsan cable-stayed bridge through analysis of measured wind data.