000013126 001__ 13126
000013126 005__ 20161114160328.0
000013126 04107 $$aeng
000013126 046__ $$k2009-06-22
000013126 100__ $$aPereira, M.
000013126 24500 $$aNew proposal for dynamic factors for en 1991-2 ultimate and serviceability states verifications on highspeed railway bridges

000013126 24630 $$n2.$$pComputational Methods in Structural Dynamics and Earhquake Engineering
000013126 260__ $$bNational Technical University of Athens, 2009
000013126 506__ $$arestricted
000013126 520__ $$2eng$$aThe actual EN 1991-2 recommendations for a quasi-static (Φ) analysis of highspeed railway bridges do not take in consideration the type of traffic of the bridge, defined in the Annex 0 of the TSI L245. Therefore, for railway bridges specially built for highspeed traffic (Category I), amplification of LM71 model by the dynamic factor Φ may be at a certain point overconservative and unrepresentative of the real traffic. The authors propose new expressions for amplification of the HSLM models featured in EN 1991-2. These expressions also take in consideration several effects, such as material damping (plus additional damping for vehicle/track interaction) and track irregularities, and apply to reinforced concrete, prestressed concrete and steel bridges. The static and dynamic displacements, accelerations, shear forces and bending moments are obtained through Fryba’s solution for a moving load series in a simply supported beam and DER Method. The mass and fundamental frequency are defined as a function of the span length, based on a confidence interval for extensive experimental results for existing railway bridges and previous research. The dynamic factor expressions are, thus, developed for vertical displacements, shear forces and bending moments, leading to an accurate quasi-static verification of the bending and shear at ULS and maximum vertical displacement at SLS. Finally, for the maximum vertical acceleration at SLS, the authors develop a critical 3d surface for the maximum acceleration permitted on a ballast track (3.5m/s2), as a function of span length, mass and fundamental frequency.

000013126 540__ $$aText je chráněný podle autorského zákona č. 121/2000 Sb.
000013126 653__ $$aDynamic factor, Eurocode, moving loads, high speed railway bridges Abstract. The actual EN 1991-2 recommendations for a quasi-static (Φ) analysis of highspeed railway bridges do not take in consideration the type of traffic of the bridge, defined in the Annex 0 of the TSI L245. Therefore, for railway bridges specially built for highspeed traffic (Category I), amplification of LM71 model by the dynamic factor Φ may be at a certain point overconservative and unrepresentative of the real traffic. The authors propose new expressions for amplification of the HSLM models featured in EN 1991-2. These expressions also take in consideration several effects, such as material damping (plus additional damping for vehicle/track interaction) and track irregularities, and apply to reinforced concrete, prestressed concrete and steel bridges. The static and dynamic displacements, accelerations, shear forces and bending moments are obtained through Fryba’s solution for a moving load series in a simply supported beam and DER Method. The mass and fundamental frequency are defined as a function of the span length, based on a confidence interval for extensive experimental results for existing railway bridges and previous research. The dynamic factor expressions are, thus, developed for vertical displacements, shear forces and bending moments, leading to an accurate quasi-static verification of the bending and shear at ULS and maximum vertical displacement at SLS. Finally, for the maximum vertical acceleration at SLS, the authors develop a critical 3d surface for the maximum acceleration permitted on a ballast track (3.5m/s2), as a function of span length, mass and fundamental frequency.

000013126 7112_ $$aCOMPDYN 2009 - 2nd International Thematic Conference$$cIsland of Rhodes (GR)$$d2009-06-22 / 2009-06-24$$gCOMPDYN2009
000013126 720__ $$aPereira, M.$$iProenca, J.
000013126 8560_ $$ffischerc@itam.cas.cz
000013126 8564_ $$s1565274$$uhttps://invenio.itam.cas.cz/record/13126/files/CD171.pdf$$yOriginal version of the author's contribution as presented on CD, section: Dynamic effects on high-speed railway tracks - ii (MS).
000013126 962__ $$r13074
000013126 980__ $$aPAPER