Seismic Behavior Analysis of a Plate-Girder Bridge Considering Abutment-Soil Interaction

원정훈,Jia Xu Wu,김상효,마호성 한국강구조학회 2008 International Journal of Steel Structures Vol.8 No.4

Longitudinal dynamic behaviors of a multi-span plate-girder bridge under seismic excitations are examined to see the effect of the abutment-soil interaction. The stiffness degradation due to the abutment-soil interaction is considered in the system model, which may play the major role upon the global dynamic characteristics of the whole bridge system. An idealized mechanical model is proposed, which is capable of considering pounding phenomena, friction at the movable supports, and the corresponding simulation method is developed. The abutment-soil interaction is modeled as the one degree-of-freedom system with nonlinear spring and damper. Using the idealized mechanical model for the bridge system, the longitudinal responses of stiffness degradation model are compared with those based on the linear system, which excludes the stiffness degradation. Results show that the stiffness degradation of the abutment-backfill system takes an important influence upon the global bridge motions and the seismic responses may be underestimated in the system only with the constant stiffness considered. Hence, it is concluded that the stiffness degradation should be taken into account in the seismic analysis of the bridge system. Longitudinal dynamic behaviors of a multi-span plate-girder bridge under seismic excitations are examined to see the effect of the abutment-soil interaction. The stiffness degradation due to the abutment-soil interaction is considered in the system model, which may play the major role upon the global dynamic characteristics of the whole bridge system. An idealized mechanical model is proposed, which is capable of considering pounding phenomena, friction at the movable supports, and the corresponding simulation method is developed. The abutment-soil interaction is modeled as the one degree-of-freedom system with nonlinear spring and damper. Using the idealized mechanical model for the bridge system, the longitudinal responses of stiffness degradation model are compared with those based on the linear system, which excludes the stiffness degradation. Results show that the stiffness degradation of the abutment-backfill system takes an important influence upon the global bridge motions and the seismic responses may be underestimated in the system only with the constant stiffness considered. Hence, it is concluded that the stiffness degradation should be taken into account in the seismic analysis of the bridge system.

온도 효과를 이용한 일부 타정식 사장교의 키-세그먼트 폐합법

원정훈,윤지현,조광일,김상효,Won, Jeong Hun,Yoon, Ji Hyun,Cho, Kwang Il,Kim, Sang Hyo 한국강구조학회 2008 韓國鋼構造學會 論文集 Vol.20 No.1

본 연구에서는 FCM 공법으로 건설되는 사장교의 최종 시공 단계인 키-세그먼트 폐합 방법으로 기존의 set-back과 reset-back 방법 대신 온도 효과를 이용한 폐합방법을 제안하여, 이를 일부 타정식 사장교에 적용하였다. 제안된 방법은 키-세그먼트 폐합 전 캔틸레버 상태인 교량 시스템의 중앙 경간부 거더 내부에 인위적인 가열 작업을 하여 거더를 신장시킨 후 키-세그먼트 폐합 후 연속교 상태에서 가열을 제거하는 방법으로, 가열 작업과 가열 제거 작업시의 시스템 변화를 이용하여 교량 시스템에 인위적인 부재력을 발생시키는 방법이다. 기존의 자정식 사장교를 일부 타정식 사장교로 변경 후 시공단계 해석을 수행한 결과, 인위적으로 발생된 부재력은 일부 타정식 사장교의 구조 시스템 특징에 부합하여 거더부의 압축력을 감소시키므로 제안된 방법은 일부 타정식 사장교에 효과적으로 적용될 수 있는 것으로 판단된다. study proposes a new key-segment closing method using thermal effect as a substitute to the process of set-back and reset-back for the FCM construction of a partially earth-anchored cable-stayed bridge. The proposed method is to artificially heat up the inside of girders located in the main span before closing the key-segment in a cantilever state. Then, the heat is removed after finishing the closure in a continuous bridge state. Using the changes in boundary conditions and structural systems, the proposed method can generate new member forces that reflect the advantage of the partially earth-anchored cable system. From the construction sequence analysis, it is found that the proposed method increases the efficiency of a partially earth-anchored cable-stayed bridge by reducing the compressive axial forces on the girders.

어린이 안전 웹툰 : 빨간 망토와 늑대

원정훈 한국방재학회 2015 한국방재학회지 Vol.15 No.5

스마트건설안전 비용의 안전관리계획서 계상 현황 분석을 통한 활성화 방안 연구

원정훈,장남권,유지영,Won, Jeong-Hun,Jang, Nam Gwon,Yu, Ji Young 한국안전학회 2022 한국안전학회지 Vol.37 No.3

This study analyzed the smart construction safety cost included in safety management plans that are approved before construction. Specifically, it refers to the cost incurred in constructing and operating a safety management system using wireless communication and facilities. Based on the obtained statistical results, an activation policy for the inclusion of the smart construction safety cost in building safety management plans was proposed. The smart construction safety cost must be included in the safety management cost; notably, this is mandated by the Construction Technology Promotion Act. However, there are some problems with the inclusion of smart construction safety costs. To analyze the problems encountered when calculating the smart construction safety cost and including it in safety management plans, in this study, statistical analysis was performed using the data of 1,334 safety management plans received at the Construction Safety Management Integrated Information (CSI) from June to August 2021. The results show that only 50.7% of the safety management plans included the smart construction safety cost although the current law mandates 100% inclusion of these costs. Thus, it is apparent that the smart construction safety costs are only included in a low proportion of sites. In addition, the calculated smart construction safety costs were shown to have a small correlation with the construction cost; moreover, they appeared to be distributed at a constant cost level. In this context, it is believed that perfunctory cost calculations were performed at most sites since the effect of the construction cost on the smart construction safety cost was negligible. Therefore, it is necessary to improve the inclusion of smart construction safety costs by strengthening the authorization process of the approval institute of safety management plans. In addition, institutional support, such as guidelines that promote the calculation and inclusion of appropriate smart construction safety costs according to the characteristics of sites, are needed.

Structural Effects of Partially Earth-anchored Cable System on Medium-span Cable-stayed Bridges

원정훈,박세준,윤지현,김상효 한국강구조학회 2008 International Journal of Steel Structures Vol.8 No.3

The aim of this study is to examine the structural effects of the partially earth-anchored cable system on cable-stayed bridges with medium main span length (between 150 and 500 m). It is assumed that the system, originally introduced as a means of reducing excessive axial force in the girder of long-span cable-stayed bridges, can be applied to medium-span cable-stayed bridges. By simulating two types of three-span cable-stayed bridges, one with the self-anchored cable system and the other with the partially earth-anchored cable system, advantages and disadvantages of the partially earth-anchored cable system are estimated. The system enhances structural behaviors for the axial force in the girder, the bending moment in the pylon, and the uplifting force at the bearing. Also, partially earth-anchored cable stayed bridges with the various numbers of earth-anchored cables are analyzed by a parametric study. The major considerations in determining the optimal proportion of earth-anchored cables is recommended.

온도 프리스트레싱 효과를 이용한 일부 타정식 사장교의 폐합방법

원정훈(Won Jeong-Hun),Ochirderi Altanzagas,윤지현(Yoon Ji-Hyun),김상효(Kim Sang-Hyo) 대한토목학회 2007 대한토목학회 학술대회 Vol.2007 No.10

건설공사 발주자의 안전보건관리 책임 부여에 대한 공사 참여자 인식 조사

원정훈 ( Jeong Hun Won ),박형근 ( Hyung Keun Park ),임세종 ( Se Jong Lim ),박용규 ( Yong Kyu Park ) 한국안전학회(구 한국산업안전학회) 2015 한국안전학회지 Vol.30 No.5

This study investigated the recognition difference among construction work participants for the assignment of the safety and health management responsibility to a client by survey. Recently, there were some studies for the client``s responsibility and duty and they suggested the client-initiative safety and health management system in order to prevent construction accidents. To supplement the existed studies, this study surveyed various construction participants such as clients, safety managers, construction managers, supervisors, others. The clients and construction managers considered the contractor as most important person to prevent construction accidents, but the safety managers and supervisors considered the client. For the opinion that the assignment of the safety and health management duty to a client is helpful, safety managers were agreed with the most. However, the clients showed the lowest agreement. The reasons that the negative opinion for the assignment of client``s the safety and health management were different between clients and other construction parties. Since, clients showed large difference to other construction participants for the recognition of works`` safety and health, the education about the works`` safety and health management should be continuously performed for clients to have correct recognition for works`` safety and health.

비상자동제동장치 적용 대형 버스의 전방 충돌 안전도 분석

원정훈(Jeonghun Won),김준년(Junnyen Kim) 대한교통학회 2021 대한교통학회 학술대회지 Vol.84 No.-

비상자동제동장치는 차량 전면에 장착된 센서를 통해 전방충돌 상황을 감지하여 장애물과 거리를 측정하고, 주변 장애물 정보를 수집하여 운행 중 추돌 사고 위험이 있다고 판단되면 운전자에게 경고를 보내거나 차량 스스로 제동장치를 작동시켜 감속 또는 정지하여 충돌을 완화하거나 회피하도록 보조하는 장치를 말한다. 이에 본 논문에서는 대형 버스가 시가지를 주행할 때 전방 충돌에 대한 안전도를 확인 및 평가하기 위하여 특정한 시나리오를 설정하고 9가지의 대형 차량속도별 비상자동제동장치의 성능 및 효과를 자동차안전도평가(KNCAP)에서 시행하는 방법을 그대로 적용하여 분석하였다. 실험을 위한 시나리오는 대형 버스 앞에 정지하고 있는 차량이 있을 경우의 충돌을 조건으로 하였으며, 대형 버스의 속도를 자동차 안전도 평가 기준에 따라 10km/h부터 50km/h까지 5km/h 간격으로 변경ㆍ조정하며 실험하였고 추가로 비상자동제동장치 작동해제 시의 정차 시험을 진행하여 둘의 결과를 비교하였다. 해당 실험의 결과는 비상자동제동장치의 중요성과 편리성에 대해 알려줄 수 있을 뿐 아니라 안전성을 보여줌으로써 운전자들 특히, 대형 버스의 운전자들에게 안전운전에 대해 다시 생각해 볼 수 있는 기회가 될 것이며, 해당장치의 사용 방법에 대한 교육자료로 또한 활용할 수 있을 것으로 기대된다.

Perfobond rib을 적용한 PSC-강 복합구조 연결부 거동에 대한 실험적 연구

원정훈(Won, Jeong-Hun),박세준(Park, Se-Jun),윤지현(Yoon, Ji-Hyun),김상효(Kim, Sang-Hyo),이찬구(Lee, Chan-Goo),김성재(Kim, Sung-Jae) 한국콘크리트학회 2008 한국콘크리트학회 학술대회 논문집 Vol.2008 No.11

건설기술진흥법 개정에 내포된 건설현장 발주자 안전관리 책임 강화

원정훈 ( Won Jeong-hon ),나예지 ( Na Ye Ji ),박기용 ( Park Ki Young ) 한국구조물진단유지관리공학회 2019 한국구조물진단유지관리공학회 학술발표대회 논문집 Vol.23 No.1

This study analyzed the major change of revised Construction Technology Promotion Act in the field of safety management. In order to increase the execution of the system of construction safety management, Construction Technology Promotion Act was revised at the end of 2018. The key issues were founded in the system of safety management plan, regular safety inspection by external professional organization, and irregular safety inspection by clients. By revised law, the role and responsibility of construction clients was enforced and the clients were recognized as leading participants in construction safety management.