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Additional temperature stresses in continuously welded rails (CWRs) are caused by track/bridge interaction (TBI) due to thermal actions. Exceeding permissible stresses in CWRs on the bridge can lead to track buckling or rail cracking, compromising the safety of railway traffic. The main aim of the conducted study is to determine the effects of the key parameters such as rail cross-sectional area, track longitudinal resistance, bridge expansion length, and longitudinal stiffness of the fixed bridge support on the reduction of additional temperature stresses in CWRs on steel truss railway bridges. To quantify the effects of these parameters, two steel railway bridges with CWRs and the maximum expansion lengths according to UIC Code 774-3 were analyzed: (1) simply supported truss bridge with expansion length of 60 m and (2) continuous truss bridge with expansion lengths of 2 × 60 m. According to the obtained results, the track longitudinal resistance had the most significant impact on additional temperature stresses in CWRs, leading to their reduction of up to 72%. The bridge expansion length and the rail cross-sectional area led to reductions of up to 25% and up to 18%, respectively. Considering the deformation criteria of TBI, the longitudinal stiffness of the fixed bridge support had a minor effect on the reduction of additional temperature stresses in CWRs. [ABSTRACT FROM AUTHOR]

Due to the rail-bridge thermal interaction, the high additional axial force in continuously welded rails on continuous bridges may lead to rail buckling or breaking. However, there is little research on the influence of the location of the fixed bearing of continuous beam on the additional force of rail. In order to study the influence of bridge bearing arrangement on the additional longitudinal force of CWR, the thermal interaction model is established for rail, and simple and continuous beams considering nonlinear stiffness and the methods are proposed to determine the locations of fixed bearings of continuous beams corresponding to the maximum additional forces in rail reaching minimum values. Multiple continuous beams with several different lengths and simple beams with three types of bearing arrangements are taken into account to find the effect laws of the locations of the fixed bearings of continuous beams on the maximum additional forces in rail. The results show that as long as the same number of continuous beams, the ratios of the distances of adjacent two fixed bearings to the distance between the two fixed bearings of the simple beams neighbour to the first and last continuous beams respectively are approximately equal to each other. Furthermore the appropriate locations of the fixed bearings of continuous beams are recommended. The results can guide designing the location of the fixed bearing of continuous railway bridge while reducing the additional axial force in continuously welded rails due to bridge thermal effect. [ABSTRACT FROM AUTHOR]

Based on the large-mass method of multi-point excitation, the nonlinear bar element was used to simulate the beamtrack contact. The track-structure interaction model of simply-supported beams was established for the first time with considering the seismic traveling wave effect. Taking 5-32 m simply-supported beams on the Shanghai-Kunming line as a case, the impact of track on the seismic performance of the bridge was analyzed under traveling wave effect. The force law of the track and pier was studied, and the influence of parameters was discussed. Studies have shown that the seismic response of the beam and substructure increases greatly under the traveling wave effect; the track is extremely sensitive to the traveling wave effect; the lower the apparent velocity is, the larger the force exerted on the track and pier is; the bearing arrangement and the sudden change of the pier stiffness significantly affect the force of the adjacent piers; with the increase of the number of spans, the track and pier force gradually increase and approach a fixed value. [ABSTRACT FROM AUTHOR]

The article offers information regarding the seismic pounding effect between neighboring simply supported beams. It focuses on the influence of the continuously welded rail (CWR) during earthquakes including the seismic response of the railway bridge, yielding uneconomic design and neglecting the influence of seismic pounding on track forces. It discusses use of several numerical modeling methods including Large-mass method and Kelvin model.