Hot-spot stress models of cutout detail on orthotropic steel bridge decks

Stress distributions along the critical section of the floorbeam cutout detail of two different cutout geometries were studied based on bridge field tests. Stress concentration at cutout detail was significant and highly dependent on cutout geometry, hence nominal stress could not be applied. The existing HSS models failed to exclude significantly nonlinear stress at original cutout detail due to their first reference points too close to free edge of cutout, and hence they significantly underestimated fatigue life. A new HSS model, with two reference points located respectively 1.0 t and 1.5 t away from the free edge of cutout, was suggested and validated for the two types of cutout geometry. Because the retrofit cutout geometry increases stress at the area 0.5 t away from the free edge, the fatigue life using various HSS models is significantly low compared to the bridge design life. It is concluded that the suggested HSS model and FAT100 may be applicable to fatigue evaluation of cutout detail with different cutout geometry. (c) 2021 Published by Elsevier Ltd.

Automated summary

Based on bridge field tests, stress distributions and fatigue life of floorbeam cutout detail are significantly affected by cutout geometries. Traditional HSS models underestimate fatigue life due to their inability to account for stress concentration at the cutout detail, while a new HSS model with revised reference points provides more accurate fatigue evaluation.