Lightweight span

City of Ithaca workers place the spans on the new Carl Sagan Bridge over Cascadilla Creek near Adams Street June 12. The bridge is constructed with lightweight bars made from fiber reinforced polymer (FRP) developed by Petru Petrina, a lecturer in Cornell's School of Civil and Environmental Engineering. Petrina led members of the student chapter of the American Society of Civil Engineers in the design and construction of the pedestrian bridge project, giving the FRP bars their first trial. The city is paying $13,800 of the cost of the $18,400 structure, with Cornell covering the balance. Nicola Kountoupes/University Photography