Abstract
The design live load of railway is divided into common railway and high-speed railway separately inKorea. Accordingly, the Korean design specification of railway specifies the impact factor for common railway and high-speed railway respectively. The impact factor for high-speed railway is based on Eurocode. Since the impact factor criteria inKoreawere established by adopting those of the Eurocode and without dedicated investigation relying on research results reflecting the domestic circumstances, thorough examination should be implemented on these criteria. Therefore the evaluation of impact factor based on field tests is required. Both dynamic and static vertical displacements are necessary to compute the impact factor. The dynamic response can be obtained from the measurement of deflection of the bridge slab crossed by the firstKoreahigh-speed train (KTX, Korea Train eXpress) running at high-speed. The main difficulties encountered are in obtaining static response because static response corresponds to the response of the bridge when the train remains immobile on the bridge or crosses the bridge at speed slower than5 km/hr. This study introduces the static response derived by applying the moving average method on the dynamic response signal. To that goal, field measurements was conducted under train speeds of5 km/hr and ranging from100 km/hr to300 km/hr on Yeonjae Bridge located in the trial section of the Gyeonbu High-Speed Railway Line before its opening. The validity of the application of the moving average method is verified from comparison of measured static response and derived static response by moving average method. Moreover, evaluation is conducted on the impact factor computed for a bridge crossed by the KTX train running at operational speed.
Highlights
IntroductionIn Korea, the impact factor currently applied for the high-speed railway magnifies the design live load by 0% to 15%
The design live load of railway is divided into common railway and high-speed railway separately in Korea
While the D214 Project conducted by the European Rail Research Institute (ERRI) Committee provide the fundamental data that served as basis for the preparation of the specifications related to the dynamic behavior of high-speed railway bridges in the Eurocode and UIC [2]
Summary
In Korea, the impact factor currently applied for the high-speed railway magnifies the design live load by 0% to 15%. The impact factor is calculated with respect to the length of the structure, Lc (m), and identical values are used indifferently for reinforced concrete, prestressed concrete, steel and composite structures Since these formulae adopt the criteria of the Eurocode [3] without dedicated investigation relying on research results reflecting the domestic circumstances, thorough examination should be implemented on these criteria. The impact factor is investigated after computation based on the dynamic displacement response measured on a high-speed railway bridge crossed by the first Korea high-speed train (KTX, Korea Train eXpress). The static response is extracted from the dynamic response by the moving average method (Equation (4))
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.