AbstractIn order to investigate the vehicle-induced vibration of a suspension bridge with CFRP cables and suspenders, three different criteria were adopted to replace the cables or suspenders of Siduhe Bridge with CFRP. The influence of traffic direction and vehicle speed on the vehicle-induced vibration were analyzed. Vehicle-induced vibration properties of suspension bridges with CFRP cables and suspenders, with a pair of CFRP suspenders, and with one CFRP suspender only were also studied in comparison with the suspension bridge with steel cables and suspenders. Results show that two-way vehicles may lead to smaller vibration responses than one-way vehicles do though two-way vehicles have more vehicles than one-way vehicles. Additionally, vehicle-induced vibration does not necessarily increase with the vehicle speed but strongly associate with speed range. In addition, no matter which criteria is adopted, the vehicle-induced responses of suspension bridges with CFRP cables and suspenders show little difference, but are larger than a bridge with steel cables and suspenders, indicating that the impact of gravity stiffness on the vehicle-induced response is larger than that of elastic stiffness. Furthermore, no matter which replacement criteria is adopted, the replacement of a pair of suspenders and one suspender both have little influence on the vertical displacement of the bridge. The tensile force of the replaced suspenders are nearly the same as the former steel suspenders when stiffness equivalence criteria is adopted, but is higher than the tensile force of replaced suspenders when area equivalence criteria is adopted, and the tensile force of replaced suspenders is the smallest when adopting the strength equivalence criteria. The replacement of suspenders has little influence on the nearby suspender in the longitudinal direction. However, when only one suspender is replaced, the influence on the nearby suspender in transverse direction is much larger the influence on the nearby suspender in longitudinal direction.