close-up view of the understructure of a bridge showing steel beams, rust, and mossy concrete

bridge infrastructure underpass construction concrete structure engineering support metal steel urban industrial architecture supporting beam pillar modern urbanity rust decay weathered strength foundation repair maintenance load framework abutment girders overpass span urbanization constructional reinforced components material weathering underneath corrosion aging degradation loadbearing tarnish wear historical iron oxide closeup view understructure showing beams mossy shsteel sopporting