CFST arches have been widely used in bridge engineering worldwide recently due to their light weight,high compressive strength,convenience of construction,and aesthetic appearance.However,studies on the reliability of this type of bridges were limited,especially on the time-dependent reliability.The timedependent change of the equilibrium configuration of the CFST arch could lead to a buckling configuration under the sustained load,which was lower than the stability bearing capacity under short-term loading.Therefore,time-dependent reliability levels for the inplane creep stability bearing capacity of CFST arch ribs,the main members of CFST arch bridges were investigated.The time-dependent limit state function for in-plane creep stability of CFST arches considering concrete creep was established and the random process of the resistance was expressed as a simple time-dependent function.