A Curved Self Anchored Suspension Bridge

Abstract

<p>San Diego has recently built a new baseball stadium in the heart of the downtown area of the city. As part of an attempt to revitalize the area, the city has commissioned a landmark pedestrian bridge from the new ballpark – over the local trolley tracks, over several sets of freight train tracks, and over a busy downtown thoroughfare – to the recently expanded convention center and the San Diego Bay. The bridge design is a self-anchored suspension bridge with a single inclined pylon. The main span of the bridge is 108m and the pylon is 40m tall. The pylon is inclined at a 60 degree angle from the horizontal and leans over the deck to support the single pair of suspension cables. 34 individual suspenders attached to the main cable support the deck from the top of the railing at one edge of the deck only. The unbalanced support conditions generate a large overturning moment due to dead and live loads on the deck. To balance this overturning moment, the bridge is horizontally curved in plan and a longitudinal tendon is placed at the top of the railing. The radial force generated by the tendon above the deck elevation generates a restoring moment which balances the forces in the bridge deck. The bridge will complete the link between the downtown and the San Diego Bay as well as serving as an icon to the city of San Diego.</p>