2013 년도한국철도학회추계학술대회논문집 KSR2013A364 전환부궤도시스템의거동특성에관한연구 A Study on Behavioral Characteristics of Transition Track System 김광우 *, 최정열 **, 김충언 ***, 이선길 *, 박용걸 **** Kwangwoo Kim *, Jungyoul Choi **, Choongeon Kim ***, Sungil Lee *, Yonggul Park **** Abstract The goal of this paper is to evaluate a structural behavior for transition track system of railway bridge deck end. In this study, the structural behavior of transition track such as the variation in static and dynamic displacements and dynamic properties (acceleration, natural frequency and damping ratio) was assessed by performing loading test using actual vehicle impact loading. As a result, we found that the static and dynamic behavior of transition track system is expected to satisfy the actual vehicle impact loading, and therefore it is inferred that the structural capacity and safety of transition track system is proved. Keywords : Transition track system, Natural frequency, Damping ratio 초록본논문의목적은철도교량단부궤도의성능개선을위해개발된전환부궤도시스템에대한정 동적거동특성및요구조건을수치해석및실내시험을통하여분석하는것이다. 본연구에서는국내고속철도궤도설계기준을바탕으로설계된전환부궤도시스템에대한수치해석을수행하고, 동특성 ( 고유진동수및감쇠비 ) 을실험적으로산출하여관련기준과비교함으로써, 전환부궤도시스템의정 동적거동특성을분석하였다. 연구결과, 본연구에서적용한전환부궤도시스템은국내철도하중에대하여충분한정 동적구조안전성을확보할수있음을실험적으로입증하였다. 주요어 : 전환부궤도시스템, 고유진동수, 감쇠비 1. 서론본연구에서는국내외적으로단부궤도의성능개선을위해개발, 적용되고있는전환부궤도시스템을국내철도하중및기준에맞게설계, 제작하여전환부궤도시스템에대한거동특성을실내시험을통해분석하고자하였다 [1-5, 6,8,9,10]. 국내고속철도교량상궤도표준도를바탕으로설계된전환부궤도시스템에대한실내시험을수행함으로써구조적거동특성및동특성 ( 고유진동수및감쇠비 ) 을실험적으로산출하였다 [10]. * 교신저자 : 서울과학기술대학교철도전문대학원철도건설공학과 (kwang@seoultech.ac.kr) ** 베를린공과대학교철도 - 궤도공학과 *** 삼현피에프기술개발팀장 **** 서울과학기술대학교철도전문대학원철도건설공학과교수
2. 실내시험 2.1 시험체설계및시험하중조건 전환부궤도시스템의시험체단면은고속철도교량상궤도표준단면및철도설계기준을준용하여단면제원을결정하고설계하였다 [10,11]. 전환부궤도시스템의폭은상부와하부각각 2.8m, 2.9m인변단면으로설계하였으며, 높이는본선일반궤도구조의 TCL(Track concrete layer) 높이를기준으로전환부궤도용받침의높이 (84mm) 를고려하여설계하였다 [10]. 전환부궤도의길이는고속철도교량신축이음부의최대유간길이조사결과를참고하여 3m로선정하였으며, 시험체의전경과제원은각각 Table 1 및 Fig. 1과같다 [10]. Table 1 Properties of components for transition track system 28 188 30 200 PL 190 92.5 t=20 2800(var.) C L 1435 UIC60 Rail Bearing of Transition track Steel plate t=28 Transition track Vossloh System 300-1 280 Rheda-2000 (Bi-Block) PL 3000 190 t=20 PL 3000 200 t=30 PL 3000 2900 t=28 22 22 40 84(var.) Description Rail Properties UIC60 Fastening system Vossloh System 300(SKL 15) Sleeper Girder TCL Rheda 2000 Bi-block T-Beam : 3,000ⅹ200ⅹ30t, 3,000ⅹ188ⅹ20t Plate : 150ⅹ2,900ⅹ28t (SM490) f ck =45MPa Fig. 1 Section of transition track system Bearing of Transition track 150ⅹ250ⅹ30t, k=121.45kn/mm 실내시험에서는정격하중 500kN 인 Actuator를이용한정, 동적재하시험을통해전환부궤도시스템의변위및가속도측정을수행하고, 또한동적가진시험을통해획득한가속도응답의자유진동파형을이용하여고유진동수및감쇠비를산출하였다 [10,13]. 본연구의실내시험에서적용한하중케이스는 Table 2와같으며, Fig. 2는동적가진시험에적용된주기하중의예를나타낸다. [10,13]. Table 2 Load case for test Static test 0 ~ 220kN (loading step : 20kN) - Case 1 (5%) Case 2 (15%) Case 3 (25%) - Dynamic test LC1 (170kN) 161.9 ± 8.1 147.9 ± 22.1 136.0 ± 34.0 LC2 (220kN) 209.5 ± 10.5 191.3 ± 28.7 176.0 ± 44.0 5, 10Hz LC3 (200kN) 105.0 ± 95 5Hz Fig. 2 Example of history load for dynamic test (5Hz)
2.2 측정센서설치정, 동적재하시험에따른전환부궤도시스템의처짐수준을파악하고자하부강판의상, 하면에변위계를설치하였으며센서설치위치도는 Fig. 3(a) 와같다. 또한동적가진하중에의해발생하는전환부궤도구조의고유진동수및감쇠비와같은동특성측정을위해 Fig. 3(b) 와같이주형및궤간중심의콘크리트상면에가속도계 (2g) 를설치하여가속도를측정하였다. D1,D3 A1 A2 D2 246 D4 D5 2900 D1 D2 3000 A1 D4 D5 A2 D3 (a) Illustration of sensor instrumentation (b) Photograph of sensor instrumentation Fig. 3 Illustration and Photos of sensor instrumentation 3. 측정결과및분석 3.1 변위및가속도검토정적최대하중 250kN 가력시측정된전환부궤도시스템의하부강판중앙부및주형하부의정적변위는 Fig. 4(a) 와같다. Fig. 4(a) 와같이정적최대하중 250kN 재하시하부강판및주형의변위량은약 0.7mm 정도로나타났으며, 동적재하시험결과역시마찬가지로 Fig. 4(b) 와같이가진하중의크기및진폭에영향을받지않고전환부궤도시스템의연직처짐기준치 0.9mm[2,3,6,8,9] 를하회하는것으로나타났다.
(a) Static displacement (b) Dynamic displacement (c) Acceleration Fig. 4 Test results of displacement and acceleration measurements 또한가속도측정결과, Fig. 4(c) 와같이전환부궤도시스템의연직가속도허용기준인 0.25g를하회하는것으로나타났다 [3,6,8,9]. 3.3 동특성검토측정가속도신호의자유진동파형을이용한 FFT분석을수행하여 Load case 별측정고유진동수및감쇠비를산출하여 Fig. 5에나타내었다. (a) Natural frequency (b) Damping ratio Fig. 5 Result of dynamic modal test for transition track
Fig. 5(a) 와같이전환부궤도시스템의고유진동수는가진하중 ( 진폭 ) 의변화에영향을받지않고약 38Hz로일정하게나타났다. 또한본연구에서수행한감쇠비분석은측정가속도신호의자유진동파형을이용하여대수감소법 (Logarithmic decrement) 에의한감쇠비추정방법을적용하였다. 측정감쇠비분석결과고유진동수와마찬가지로 Fig. 5(b) 와같이가진하중의영향을받지않고일정한수준 ( 약 2.38%) 을유지하는것으로나타났다. 4. 결론국내고속철도궤도설계기준을준용하여설계및제작한전환부궤도시스템은국내철도하중에대한충분한정, 동적구조안전성을확보할수있음을실험적으로입증하였다. 또한전환부궤도시스템의고유진동수는국내철도운행열차속도대역에서공진발생의위험은없는것으로분석되었으며, 측정감쇠비는강합성구조형식의감쇠비기준을만족하는것으로분석되었다. 따라서본연구에서수행한현장적용을위한전환부궤도시스템의실물시제품실험결과전환부궤도시스템은국내주행열차하중에대한구조적안전성을입증하였다. 후기본연구는국토교통부국토교통과학기술진흥원미래철도기술개발사업의연구비지원 ( 과제번호 : 12PRTD-C059777-02, 과제명 : 콘크리트궤도가부설된철도교량상장대레일축력저감및단부사용성확보를위한한국형횡단궤도시스템개발 ) 에의해수행되었으며, 관련자분들모두에게감사드립니다. 참고문헌 [1] Deutsche Bahn, DB Netz AG (2008) Bridge deck Ends, Check for serviceability limit state of superstructure, DS804 Appendix 29 (German language). [2] Deutsche Bahn, DB Netz AG (2003) Richtlinie 804.5202 (German language). [3] Rudolf Seidel (2000) Feste Fahrbahn auf großen Stahlüberbauten der NBS Hannover-Berlin, EI- Eisenbahningenieur (51), pp. 23-29 (German language). [4] Deutsche Bahn, DB Netz AG (1995) Anforderungskatalog zum Bau der Fahrbahn, 3. Uberarbeitete Auflage, Stand, Catalogues for construction of slab track (German language). [5] Edgar Darr, Werner Fiebig (2006) Feste Fahrbahn, Konstruktion und Bauarten für Eisenbahn und Straßenbahn, ISBN 3-8266-1485-2, Eurail press (German language). [6] J.I. Lim, S.O. Song, J.Y. Choi, Y.G. Park (2013) Experimental Study on Applying a Transition Track System to Improve Track Serviceability in Railway Bridge Deck Ends, Journal of the Korean Society for Railway, 16(3), pp. 207-216. [7] J.I. Lim, S.O. Song, J.Y. Choi, Y.G. Park (2013) Experimental Study on Characteristics of Deformation for Concrete Track on Railway Bridge Deck End induced by Bridge End Rotation, Journal of the
Korean Society for Railway, 16(3), pp. 217-225. [8] K.H Lee (2013) Applying transition track system to improve track performance in a railway bridge deck ends, Master's thesis, Seoul National University of Science & Technology. [9] K.H Lee, J.Y Choi, M.C Kim, Y.G Park (2012) The Behavior Analysis of Track of Railway Bridge Ends Deck Installed Transition Track, 2012 Autumn Conference & Annual Meeting of the Korean Society for Railway, Gyeongju, pp.1342-1352 [10] G.Y. Jo, J.Y. Choi, B.J. Park, Y.G. Park (2013) A Study on Evaluation of Fatigue Behavior for Transition Track System of Railway Bridge, 2013 Autumn Conference & Annual Meeting of the Korean Society for Railway, Daegu.(Submitted) [11] Korea Rail Network Authority (2011) Railway design Standard (Track part). [12] Korea Rail Network Authority (2011) Railway design Standard (Railway bridge part). [13] D.S. Chun, J.Y. Choi, H.Y. An, Y.G. Park (2008) Behavior of Fastening system of HSR bridge ends deck on slab Track installed Bridge, 2008 Autumn Conference & Annual Meeting of the Korean Society for Railway, Gwangju, pp. 1624-1633.