Overloading simulation fatigue experiment of bridge member with and without CFRP reinforcement

Abstract

In order to realize accurate evaluation of the fatigue damage and failure risk for existing bridges which suffering vehicle overloading,fatigue experiments of bridge component with and without carbon fiber reinforced plastics(CFRP) reinforcement were carried out based on vehicle load survey.Three overloading states were simulated,which were general state,serious state and combine state.The capacity after overloading was tested,and the performance parameters,such as section strain,crack pattern,maximum crack width,deflection,were monitored,then the development law of above parameters versus the number of fatigue cycles under overloading were investigated.The experimental results indicate that the capacity cannot be used to refer the service performance of bridge,and a better way to reflect the overloading effect is fatigue damage,which affects the deformation capacity of the bridge structure.The section strain increases with the number of fatigue cycles under low cycle fatigue load.The plane-section assumption is still satisfied approximatively till the end of the fatigue cycle.The fatigue performance of bridge component under overloading should be evaluated using steel rebar strain and mid-span deflection as the main control indexes.