In order to investigate the structural response of CRTS Bi-block ballastless track system on continuous bridge under dynamic train load

and predict the fatigue life of the ballastless track structure on the bridge

based on the principle of bridge-rail interaction and train-track-bridge coupling dynamics

a (40+64+40)m continuous bridge of Nanchang-Jingdezhen-Huangshan high speed railway is taken as the research object

the refined simulation model of continuous beam bridge-ballastless track system considering the nonlinear constraints between bridge

bearing and abutment

shear nail

baseplate

elastic cushion

track plate

fastener and rail is established by using the finite element method. The dynamic response characteristics of coupling system and the longitudinal force distribution law of CWR are studied

and the structural fatigue characteristics of ballastless track laid on continuous beam bridge are analyzed. The results show that: the maximum compressive stress of rail under temperature load appears at both ends of continuous beam

and the maximum tensile stress appears in the middle of bridge span. The maximum tensile stress of rail under vertical load appears near the pier of continuous beam bridge

and the maximum compressive stress appears in the middle of bridge span. Under the action of braking load

the maximum tensile and compressive stress of rail appear near the bridge pier. The longitudinal force of the rail is controlled by the temperature load

and the maximum stress is 143.1 MPa

meeting the specification requirements; Under the action of dynamic train load

the maximum tensile and compressive stress of rail on simply-supported bridge and continuous bridge are equivalent. The maximum tensile stress of track plate appears near the limit groove in the middle span of continuous beam bridge

the tensile stress at the bottom surface of track plate is greater than that at the top surface. The maximum tensile stress of the baseplate occurs near the main pier of the continuous beam bridge

the tensile and compressive stress at the top and bottom surface of the baseplate are basically the same. Under the action of dynamic train load

the service life of the most vulnerable part of the rail is about 27.1 years

and there will be no fatigue failure to track plate and baseplate during service.