INFLUENCE OF VEHICLE AND AMBIENT TEMPERATURE ON THE FATIGUE DAMAGE OF STEEL BRIDGE DECK SURFACING

The fatigue damage characteristic of the steel bridge deck epoxy asphalt concrete surfacing due to repeated vehicle load and ambient temperature, is analyzed by using the method of damage mechanics. From the method, the fracture, stress and strain field in the composite beam for fatigue tests are presented. As an example, using the composite beam fatigue test on the steel bridge deck epoxy asphalt concrete surfacing of Yangtze River Bridge, a predictive formula for the fatigue life of the beam is proposed. Fatigue life calculated accounting to thermal action was less than not. The value was decreased by approximately 44%. The results indicate that stiffness modulus of the asphalt mixture surfacing will vary with the fluctuate of ambient temperature, leading to change in mechanical characteristic and fatigue life of steel bridge deck asphalt mixture surfacing composite structure. It is too simplified to take fatigue damage characteristic of asphalt mixture surfacing only as the function of moving vehicle, and thermal action should not be ignored. Furthermore, epoxy asphalt surfacing appears to provide good fatigue resistance.