Özet:
Orthotropic steel decks (OSDs) are one of the most chosen solutions when the dead-weight
is the primary concern. Due to their light construction style and low rigidity fatigue have
been observed as cracks running through especially in the connections because of
concentrated and residual stresses at welded details. Studies concerning the cases which use
(RR) butt-welded connections are limited in the literature. In this study, a set of cyclic loading
experiments is carried out for the investigation of the fatigue life and crack propagation
characteristics of full-scale rib-to-rib (RR) butt-welded connections with trapezoidal crosssections. Two repairment methods based on bonded carbon fiber reinforced polymer layers
(CFRP) and bolted steel plates (BSP) for the failed specimens are utilized and fatigue life
improvements are tested. The cyclic test rig is first verified under static loading with strain
gage readings which are compared to finite element simulations. Crack growth
characteristics are observed as provided by dye-penetrant and dynamic stiffness crack
detection methods. Crack lengths against the number of cycles were recorded for
construction of the fatigue strength (S-N) Curves as given in AASHTO (2007). The test
revealed that as long as the bond quality of the CFRP layers the steel plates were maintained,
the decrease in stress demand was enough to extend the fatigue life from AASHTO fatiguedesign Category E’ for the unrepaired configuration to the infinite fatigue life range. Test
results also showed that the dynamic stiffness curve was drastically improved for the
repaired specimens. To better understand the experimental results a numerical study based
on finite element simulations is undertaken as well. The results indicate a remarkable
decrease in stress levels in fatigue sensitive details after the application of proposed repair
methods. Overall, the performance of these two lightweight methods for repairing movable
OSD proved to be efficient and durable.
