FBG센서를 이용한 콘크리트 충진 FRP 스트럿 보강 PSC 교량의 스트럿 거동 분석

정원석,강동훈,안주옥,Chung. Won-Seok,Kang. Dong-Hoon,An. Zu-Og 한국방재학회 2009 한국방재학회논문집 Vol.9 No.6

최근 국내에서는 PSC(Prestressed Concrete) 박스 거더 교량의 교폭을 늘리고 자중을 줄이기 위한 목적으로 박스의 수를 줄이는 대신 콘크리트 충진 FRP(Concrete Filled FRP, CFFRP) 스트럿을 상판 캔틸레버 부분에 설치하는 공법이 시공되고 있다. 이러한 CFFRP 스트럿은 사례가 많지 않은 교량 구조물로서 설계 및 시공에서의 불확실성을 제거하기 위해 교량 시스템에서의 스트럿 거동을 실험적으로 분석할 필요가 있다. 따라서 본 연구에서는 대상교량에 대해 현장시험을 실시하여 CFFRP 스트럿의 국부 거동을 분석하고자 한다. 특히 전자기파 간섭에 대해 면역이 우수한 광센서인 FBG(fiber Bragg grating) 센서를 기반으로 시험을 실시하여 잡음이 없는 우수한 응답을 성공적으로 획득하였다. 현장시험에서는 재하트럭의 속도와 횡방향 위치를 매개변수로 시험을 실시하였다. 그 결과 CFFRP 스트럿은 하중재하 위치와 속도에 관계없이 압축상태에 존재하고 있으며, 통과 차량의 횡방향 위치가 CFFRP 스트럿의 거동에 민감한 요소임을 확인하였다. Recently, a new PSC (Prestressed Concrete) bridge system, which is supported by Concrete-filled fiber-reinforced polymer (CFFRP) strut, has been introduced. This bridge is able to reduce self-weight and increase the width of traditional PSC bridges. However, no relevant research has been reported on local behavior of CFFRP strut in the bridge system. The purpose of this study is to investigate local behavior of CFFRP struts using fiber Bragg grating (FBG) sensors. Field tests were performed to examine the hoop strains and longitudinal strains of the FRP strut under various lateral positions and velocities of a test truck. It has been observed that CFFRP strut is under compression regardless of vehicle speed and location. However, the CFFRP strut is sensitive to the lateral position of vehicles in terms of strain magnitude. Results also indicated that the FBG sensors can faithfully record the hoop and longitudinal strains of the FRP strut without electro-magnetic interference.

강합성교 설계를 위한 하중분배계수 간략식

정원석,Chung, Wonseok 한국강구조학회 2005 한국강구조학회 논문집 Vol.17 No.2

강합성 교량의 설계시 종방향 모멘트에 하중분배계수를 고려하여 주형의 최대 모멘트를 계산하고 있다. 이러한 하중분배계수식은 1930년경부터 AASHTO 시방서에 채택된 이후 소폭의 수정을 거듭해 오다가 1994년 LRFD 시방서부터 전폭적으로 수정되었다. LRFD 시방서의 하중분배계수 식은 실제 교량의 거동을 비교적 정확히 반영하고 있는 것으로 알려져 있다. 하지만 LRFD식은 설계모멘트 결정단계에서는 확정할 수 없는 종방향 강성계수를 포함하고 있으므로 반복을 통한 설계를 요구한다. 이러한 LRFD식이 내포하는 반복 설계과정으로 인해 실무에서는 널리 쓰이지 않고 있는 실정이다. 따라서 본 연구에서는 반복 설계과정을 필요로 하지 않는 I형 강합성교량의 하중분배간략식을 LRFD식에 근거하여 도출하였다. 간략식의 검증을 위해 43개의 대표교량의 유한요소해석을 통해 구한 엄밀 하중분배계수와 AASHTO LRFD 식, AASHTO Standard 식으로 구한 하중분배계수와 비교하였다. 그 결과 간략식이 구조물의 안전성을 확보하면서 반복계산을 필요로 하지 않는 것으로 확인되었다. The AASHTO wheel load distribution factor (LDF) equation has been with us since 1931 and has undergone minor modifications. In 1994, an entirely new procedure was introduced in the AASHTO LRFD code based on parametric studies and finite element analyses. However, this LDF equation involves a longitudinal stiffness parameter, the design of which is not initially known. Thus, an iterative procedure is required to correctly determine the LDF value. The increased level of complexity puts undue burden on the designer resulting in a higher likelihood for misinterpretation and error. In this study, based on current AASHTO LRFD framework, a new simplified equation is developed that does not require an iterative procedure. A total of 43 representative composite steel girder bridges are selected and analyzed using a finite element model.The new simplified equation produces LDF values that are always conservative when compared to those obtained from the finite element analyses and are generally greater than the LDF obtained using AASHTO LRFD specification. Therefore, the proposed simplified equation is expected to streamline the determination of LDF for bridge design without sacrificing safety.

콘크리트 충진 FRP Tube의 실험적 휨거동 분석

정원석,이창선,안주옥,Chung. Won-Seok,Lee. Chang-Sun,An. Zu-Og 한국방재학회 2011 한국방재학회논문집 Vol.11 No.5

본 연구에서는 FRP 재료를 활용한 구조시스템인 콘크리트 충진 FRP 튜브 시스템을 대상으로 동특성 시험 및 정적 휨재하 시험을 실시하여 구조거동을 실험적으로 분석하였다. 실험체는 원통형 FRP 쉘에 철근을 삽입하고 콘크리트가 충진되어 합성된 하이브리드 구조체이다. 실험 프로그램은 2개의 단계로 구분하였다. 첫번째 단계는 콘크리트 충진 FRP 튜브 시스템을 대상으로 동특성 실험을 실시하여 고유진동수 및 모드를 분석하였으며, 두번째 단계는 하이브리드 형태의 대상 구조물의 구조거동 및 파괴형태를 파악하기 위해 4점 재하실험을 실시하고 파괴거동을 분석하였다. 그 결과, 콘크리트 충진 FRP 튜브시스템은 다양한 재료가 사용된 하이브리드 시스템이나 전형적인 보 구조물의 동특성과 파괴거동을 나타내고 있음을 확인하였다. 콘크리트 충진 FRP 튜브는 FRP 재료의 고강성, 고강도 등의 구조적 거동을 보일 뿐만 아니라 철근콘크리트의 파괴거동과 유사한 연성파괴 형태를 나타내었다. This study presents the experimental investigation of concrete filled FRP (Fiber Reinforced Polymer) tube system. A new structural system was developed that combines a FRP shell with a reinforced concrete core for use as flexural members in civil structural applications. The experimental program involved two phases. First, the dynamic characteristics were identified. The second phase involved the measurement of the nonlinear static behavior until failure. The failure mode of FRP only was known to be brittle. However, the results of the proposed system showed that the failure mode was ductile as the system was a hybrid system with reinforced concrete. The proposed system takes advantages of structural advantages of FRP structure as well as the failure mode of reinforced concrete material.

광섬유 격자센서를 이용한 철도 판형교의 증속 실험

정원석,강동훈,최은수,김현민,Chung, Won Seok,Kang, Dong Hoon,Choi, Eun Soo,Kim, Hyun Min 한국강구조학회 2005 한국강구조학회 논문집 Vol.17 No.6

본 연구는 광섬유 브래그 격자 (fiber Bragg grating, FBG) 센서를 이용하여 보강이 실시된 철도판형교의 수직처짐을 산정하고 이를 통해 교량의 정적 및 동적 거동을 모니터링 하는데 목적이 있다. 7개의 센서로 다중화(multiplexing)된 FBG 센서 2쌍을 지간 12.9 m인 철도 판형교의 상부와 하부 플랜지의 표면에 부착하였다. 이렇게 수평 배치된 FBG 센서로부터 직접 곡률을 측정하고 기하학적인 처짐-곡률관계와 회귀분석을 통해 교량의 처짐을 유추하였다. FBG 센서의 정확도를 검증하기 위해 교량의 중앙 지점에 기존의 전기식 변형률 센서와 처짐계를 설치하였다. 교량의 거동을 측정하기 위해 열차 재하실험과 증속실험을 실시하였다. 증속실험은 열차의 속도를 10 km/h 에서 90 km/h까지 10 km/h 씩 증가시키며 교량의 동적 거동을 분석하였다. 측정 변형률을 비교한 결과 FBG 센서와 전기식 센서가 최대오차 7%이내의 우수한 상관관계를 보였으며, 본 연구에서 제안된 실험법으로 유추된 최대처짐을 처짐계를 이용한 결과와 비교하였을 때 5% 이내의 오차를 보였다. 따라서 철도판형교의 안전성 평가를 위한 처짐 모니터링 시 FBG 센서의 적용성이 우수하다고 판단된다. This study investigates an existing steel plate girder railroad bridge after superstructure rehabilitation to monitor static and dynamic responses using Fiber Bragg Grating (FBG) sensors. This paper also presents an experimental technique to estimate the vertical deflection of the bridge using FBG sensors. Seven FBG sensors are multiplexed in a single optical fiber and installed in parallel pairs along the length of the bridge, with one set at the top flange and the other at the bottom flange. In addition to FBG sensors, a conventional electric strain gauge and anLVDT are installed at the mid-span of the bridge for comparison. A test train consisting of one locomotive is placed at the center of the bridge to produce the maximum static effect. The train is also made to pass over the bridge at different speeds ranging from 10 km/h to 90 km/h to monitor the dynamic response of the bridge. This study demonstrates that the measured strains using the FBG sensor compared well with the readings from the electric strain gauge. The results show that the proposed instrumentation technique is capable of estimating the vertical deflection of the bridge for various loading conditions, which is crucial in structural health monitoring. Several dynamic characteristics of the bridge were also identified.

잊혀진 댄디를 찾아서 -19세기 고전적 댄디즘의 사회,미학적 범주들-

정원석 ( Wonseok Chung ) 한국뷔히너학회 2015 뷔히너와 현대문학 Vol.0 No.45

In der vorliegenden Arbeit wird der Versuch unternommen, unter besonderer Berucksichtigung des klassischen Dandysmus im 19. Jahrhundert, sozioasthetische Elemente des Dandysmus herauszustellen, vor allem in Bezug auf den geistigen Aristokratismus, die kunstlerische Selbststilisierung des einzelnen Helden, oder die Asthetik des Kunstlichen und Anti-Naturlichen. Daraus ergibt sich, dass der Begriff des Dandysmus als Komplex des Sozialtypus und zugleich des asthetischen Prinzips angesehen wird. In seinen ersten Entwicklungsphasen ist der Dandysmus als Ausdruck einer bestimmten Geistes- und Lebenshaltung anzusehen, welche die aristokratische Attitude verrat, sich durch einfache, erlesene Eleganz von anderen unterscheiden zu wollen. Dieser Aspekt hat sich auf die franzosische Kultur ausgewirkt und zum ‘geistigen’ Aristokratismus gefuhrt, der als kunstlerischer Stolz einem neuen Typus des Kunstlers inharent sein soll. Seine Originalitat und sein Wille zur Andersartigkeit machen den Dandy zwar zum Outsider, aber seine verfeinerte Ausdrucksweise erlaubt der Gesellschaft andererseits ihn als Insider zu akzeptieren. Der englische Dandy, beispielsweise dessen erster Vertreter Brummell, war Quasioder Pseudo-Kunstler durch sein Wesen selbst, durch den Ton, den er anschlug, den Blick, die Gebarden etc. Dies unterscheidet ihn vom anderen Dandy-Typus, der wie Barbey oder Baudelaire literarische Werke schopft. In dieser Arbeit wird die Schonheit des Kunstlichen vor allem in Bezug auf die Asthetik der Anti-Natur verstanden.

폐경 전 성인 비만여성의 비만도와 요추전만도의 상관성 분석

정원석 ( Won Suk Chung ),김성수 ( Sung Soo Kim ),송미연 ( Mi Yeon Song ) 한방재활의학과학회 2003 한방재활의학과학회지 Vol.13 No.3

Background : Obesity is associated with degenerative arthropathy of which over-weight itself can be a one of the stressor on joints. In addition, obesity also affects weight bearing joints by general activity or exercise. Objectives : The goals were to investigate correlation between obesity and lumbar lordosis in obese pre-menopausal Korean females. The hypothesis were tested that there is a correlation between obesity and lumbar lordosis. Design : A cross-sectional evaluation of 44 Females (baseline age 30.77±6.46) with body mass index 31.53±3.82 kg/m2. Body composition was measured using bioimpedence analysis (BIA) and Anthropometry was done by same observer. lateral whole spine X-ray was taken in standing position to measure lumbar lordotic angle(LLA), Ferguson angle(FA) and lumbar gravity line(LGL). Results : Body mass index (BMI) had a negative relationship with LLA (γ=-0.469), FA (γ=-0.347) and LGL (γ=-0.389). Body fat rate had a negative relationship with LLA (γ=-0.385). Waist circumference had a negative relationship with LLA(γ=-0.345) and LGL(γ=-0.346). WH ratio had no relationship with lumbar lordosis. Conclusions : The data shows that obesity related to body shape and mechanical structures. Obesity can be a one of the stressor of musculo-skeletal system especially lumbar spine, and one of the causing factor of lumbar spinal disease.

한국 과체중 갱년기 도시 여성의 비만도,일상생활 스트레스, 자존감, 식이태도, 우울증,스트레스 반응척도와 갱년기 증상의 연관성

정원석 ( Won Suk Chung ),황미자 ( Mi Ja Hwang ),김성수 ( Sung Soo Kim ),황덕상 ( Deok Sang Hwang ),송미연 ( Mi Yeon Song ) 한방비만학회 2008 한방비만학회지 Vol.8 No.1

Obesity and climacteric symptom are affected by various cultural, social and psychological factors. This study is performed to recognize the relationship between obesity, climacteric symptom, and other social and psychological factors such as self-esteem, depression, eating attitude, stress response and social readjustment rating. Methods SRRS(social readjustment rating scale), SES(self-esteem scale), SRI(stress response inventory), BDI(Beck depression inventory), KEAT-26 (Korean Eating Attitude Test-26) and Kuperman index were given to 43 peri-menopausal women aged 45-55 and BMI ≥23. They were given written consent and this study is performed under the permission of institutional review board of Kyung Hee East-west Neo Medical Center. And height, body weight, waist circumference were measured. These variables were treated by correlation and regression analysis for finding effect factors of climacteric symptom. Result BMI and WC were not related to climacteric symptom. There were significant correlation between KEAT-26(r=0.4388, p=0.004), SES (r=-0.4748, p=0.001), SRI(r=0.6941, p<0.001), BDI(r=0.6354, p<0.001) and Kuperman index. In multiple regression, SRI was find to be a prediction factor of Kuperman index.(Kuperman index=19.033+0.7SRI(R2=0.490)). Conclusion Climacteric symptom is related to self-esteem, eating attitude, depression and stress response. And the most important prediction factor of climacteric symptom is stress response. So managing of stress response may be essential to treating climacteric syndrome. And it is necessary to study about climacteric symptom with many other effective factors of various peri-menopausal subjects.

쉴러와 보수혁명 -보수혁명적 관점에서의『빌헬름 텔』연구

정원석 ( Won Seok Chung ) 한국뷔히너학회 2011 뷔히너와 현대문학 Vol.0 No.37

In der vorliegenden Arbeit wird Schillers letztes vollendetes Drama Wilhelm Tell zum erstenmal im Licht der ``Konservativen Revolution`` analysiert. Das heißt, es werden die konservativen und zugleich revolutionaren Eigenschaften des Werkes untersucht. Wenn man aber auf historische Voraussetzungen des brisanten Tell-Stoffes Rucksicht nimmt, zeigt das Werk im Grunde kaum unmittelbare Beziehungen zur Franzosischen Revolution. Schiller hat die franzosische ``Totalrevolution`` (E. Burke) ausgespielt, indem er den schweizerischen Befreiungskampf ganz nach dem Muster der alten Revolution darstellt. Der Position der Konservativen Revolution entspricht das geistige Erwachen des Individuums, welches im kulturellen Standpunkt konservativ ist, und damit das Verhalten, welches die dementsprechende praktische Tatkraft enthalt. Die konservativ-revolutionaren Zuge, beim konservativen Aufstand von Tell dargestellt, zeigen sich bestens in der Rutli-Szene des Werkes. Weil das Werk vor allem von friedlichen Charakter gepragt ist, steht das im deutlichen Gegensatz und Widerspruch zur Franzosischen Revolution. Die scheinbar revolutionaren Charaktere beziehen sich auf keine totale Veranderung, keine totale Vernichtung des geschichtlich erfahrenen berechtigten Alles, sondern auf den Kampf fur das historisch legitimierte Naturrecht. Gerade in diesem Sinne sollte man da von "antirevolutionar" sprechen. Denn die revolutonaren Zuge im Werk richten sich lediglich auf den volkischen Widerstand gegen eine fruhabsolutistische Fremdherrschaft um der Wahrung des alten Rechtsbestandes willen. Die vorliegende Arbeit hat herausgestellt, dass das Phanomen der volkischen Revolte im Rutlibund dem Konzept der Franzosischen Revolution widerspricht und vielmehr der Konservativen Revolution naher kommt. Die Revolution im Begriff der Konservativen Revolution bedeutet keinen neuen Beginn unter der Bedingung eines radikalen Durchbruchs mit der Vergangenheit, wie bei der Revolution von 1789. In der vorliegenden Arbeit hat es sich herausgestellt, dass der volkische Aufstand im Sinne der Restauration eines durch Despotismus gestorten Rechtszustandes dem konservativ-revolutionaren Konzept entspricht. Von diesem Standpunkt aus gesehen, fuhlen sich die Eidgenossen im Rutlibund als die rechtmaßigen Erhalter der Ordnung. Schiller hat gar nicht ein Geschichtsbild unter entschiedenem Bruch mit der Vergangenheit verworfen. In diesem Punkt lassen sich Schiller und ebenso konservative Revolutionare im 20. Jahrhundert als Traditionalisten betrachten, die den Widerstand gegen das tyrannische Joch von außen leistet und zugleich jene rechtmaßigen Werte und Systeme des Vergangenen wiederherstellen wollen. Schiller hat jedoch niemals die Entwicklung des neunen Lebens und der neuen Gesellschaft vernachlassigt. Weil Tell dauernd auf Individualismus beharrt und doch endlich zur entscheidenden Tat fur die Schopfung einer neuen politischen Gesellschaft kommt.

특집논문 2-1 : 임상의사가 본 드라마 제중원

정원석 ( Won Suk Chung ) 연세대학교 의과대학 의사학과 의학사연구소 2010 연세의사학 Vol.13 No.1

I started posting “Medical Facts in Jejungwon” to my blog (http://blog.naver.com/clinicmirae), so that the general audience could further enjoy watching the show “Jejungwon” and so more people could get to know the correct history of the hospital Jejungwon. Jejungwon is different from other numerous medical dramas in that historical fact is also conveyed. Not only that, certain medical techniques and procedures that are portrayed are very sophisticated and ahead of its their time ; the doctors of the show are bright, possess immense knowledge, and have very good surgical skills. The show also touches upon a variety of issues that are still problematic in the medical field today and gives the viewers an overview of the whole course of medical training, which is still somewhat shrouded in mystery to those who have never been to medical school. The writer of the script for “Jejungwon” sought medical consultation from me for the show (which included conditions such as varicose veins, lung cancer, pneumothorax, and bowel perforation). I also had the chance to lend a hand by standing-in as a surgeon in an operation scene. Through the TV drama “Jejungwon,” I was able to gain deeper insight into the historical meaning and background of the actual institution, and by means of internet blogging, I have been able to share that information with the general audience.

에른스트 윙어의 『노동자』와 괴테(2) -"노동자" 형상과 "파우스트적" 인간 간의 (탈)정치적 연관성에 대해서-

정원석 ( Won Seok Chung ) 한국독어독문학회 2009 獨逸文學 Vol.111 No.-

Ausgehend von Thomas Manns vermutlich erstem unmittelbarem Hinweis auf die Verbindung zwischen Jungers Arbeiter-Konzept und der Figur Faust, habe ich die Gemeinsamkeiten untersucht, indem ich vor allem auf motivische Beruhrungspunkte von Jungers `Arbeiter` zu Goethes Vorstellung des alten Faust als Tatmenschen fokussiert habe. Der Arbeiter, in seiner Fixierung auf die moderne Technik, kann von daher als Spiegelung `faustischer` `Mannerphantasien` bestimmt werden, womit er sich in die damalige Faust-Rezeption einreiht. Einem so zum Ausdruck gebrachten "faustisch-elitaren Lebensgefuhl" kann neben dem Arbeiter auch noch die Schriften Der Kampf als inneres Erlebnis und Die totale Mobilmachung zugeordnet werden. Gerade unter Berufung auf den `faustischen` Tatendrang wird "strebendes Bemuhen" als "das aktive Prinzip" des Arbeiters propagiert. `Strebendes Bemuhen`, das sich auf Faust II beruft, gewahrleistet fur Junger den titanischen Triumph des Menschen gegenuber den Elementen der Natur. Der unerschopfliche Tatendrang beruht auf `faustisch` ausgerichtetem Emporsteigen der Lebensvitalitat. Insbesondere im Hinblick auf Fausts kolonisierende Tatigkeit in der letzten Szene haben wir beobachtet, inwieweit Jungers Arbeiter den ideologischen Verwerfungen, wie insbesondere im fruhen 20. Jahrhundert aufgetreten, unterstellt werden kann. Infolgedessen steht der Junger`sche Arbeiter im zeitspezifischen Zusammenhang des imperialistischen und totalitaren Expansionsdrangs, der unter politisch-ideologischem Aspekt-gleichviel ob Junger dies unterstutzen wollte oder nicht-parallel zur zeitgenossischen Faust-Rezeption zu sehen ist. In der Versohnungsstimmung der Nachkriegszeit bestimmt Junger in der erneuten Beschaftigung mit der Arbeiter-Thematik offenkundig seine geistige Nahe zu Goethe noch genauer. Gerade an diesem Punkt steht Jungers Koalition mit Goethe fur die Distanzierung von der ihm selbst vorgeworfenen, fruheren politischen Degeneration, da er mit dem Arbeiter besonders von den Nationalsozialisten positiv aufgenommen worden und dadurch nachhaltig beschadigt war. In den Adnoten zum Arbeiter (1964) beabsichtigt Junger, sein Arbeiterbild als einen neuen Typus des Menschen metaphysisch auszulegen. Die "innere Erfahrung" der Arbeiter-Gestalt, die fur Junger als Goetheaner zentral wird, bietet einen deutlichen Anhaltspunkt fur die außerst asthetische Entpolitisierung des Arbeiter-Entwurfs, da das Moment der inneren Erfahrung an sich entschieden nicht-politisch ist. Dieser Gedanke ist auch in der Konzeption eines Weltstaates aus dem Jahr 1960 im Keim enthalten, denn der `Weltstaat` gestaltet den "Ubergang der Gestalt des Arbeiters von planetarischer Macht zu planetarischer Ordnung". Die "Vergeistigung" der Welt, wie sie der `Weltstaat` naher bringt, wird fur Junger zum Kennzeichen einer Zukunftsutopie.