Experimental Study of the Fatigue Behavior of Profiled Steel Sheeting-Concrete Composite Bridge Decks with Perfobond Connectors

Abstract:

A continuous profiled steel sheeting-concrete composite bridge deck specimen with perfobond（PBL） connectors was tested to study the mechanical behavior at variable amplitude fatigue load. The specimen is 9.25 m long and 1.5 m wide， the thickness of the profiled steel sheeting is 3 mm， and the depth of concrete is 24 cm. The mid-span deflection， the strain of concrete and reinforcement， and the distribution of cracks and crack widths at the hogging moment region， as well as the procedure of the degeneration of stiffness and the fatigue failure mode were obtained and discussed. The test results show that the mechanical behavior of the composite deck specimen deteriorats with the increase in the fatigue loading times. The specimen does not fail at a fatigue loading of 600×10⁴ times， which shows that the composite deck has a high fatigue strength. The fatigue failure mode of the specimen is the steel sheeting crack at the mid-span， and the fatigue crack initiats at the welding part of the PBL connectors and steel sheeting. Meanwhile， the maximum crack width of concrete at the hogging moment region reaches 0.2 mm at static load. The applicability of the existing S-N curve to the composite deck was analyzed by using the linear damage accumulation rule.

Key words:composite bridge deck;profile steel sheeting;fatigue;failure mode;crack