The research project "Holistic assessment of steel and composite bridges according to criteria of sustainability" provides a concept in order to evaluate road bridges under the consideration of three aspects: ecological, economic and social/functional quality. The example of a motorway crossing demonstrates how life-cycle assessment is effected by different structural systems and materials. An integral steel-composite bridge is compared to a two-span steel-composite bridge including bearings and expansion joints. In addition to that there are two design variations for both bridge types: a) traditional steel structure with anticorrosive coating system and b) structure with self-weathering steel. The most significant difference is detected in the maintenance stage, during which the replacement of the coating system is required or not.