Continued Monitoring of the Varina-Enon Bridge - Estimation of Effective Prestress

The Varina-Enon Bridge, which carries I-295 over the James River near Richmond, has had a history of issues in the approach spans including: failure of two tendons due to corrosion, significant cracking, and active opening and closing of match-cast joints under high traffic loads concurrent with high positive thermal gradients. A long-term plan is necessary for monitoring the structure to ensure its continued safe transport of traffic along this important corridor. The proposed monitoring will occur over several years in order to evaluate the level of effective prestress in the external tendons and to better quantify the thermal gradient. These assessments will assist in developing accurate load ratings and in determining if, and when, additional tendons should be installed in the bridge in order to achieve a sufficient level of confidence in the capacity and long-term durability of the structure.