stroganov pedestrian bridge (saint petersburg)

tree walkway park waterway garden plant city neighbourhood yard road transport estate backyard street lane bridge petersburg spans small channel kamenny island parallel embankment river singlespan reinforced concrete beamsplit system slab decorative tides supports meters long wide superstructure constructed monolithic slight curvature lower belt abutments massive natural foundation stroganov pedestrian saint black alignment grafova entrance primorsky district 31 metal prestressed beams