M. Saiidi, C. Cruz, D. Hillis,
Volume 8, Issue 1 (3-2010)
Three unconventional details for plastic hinges of bridge columns subjected to seismic loads were developed,
designed, and implemented in a large-scale, four-span reinforced concrete bridge. Shape memory alloys (SMA),
special engineered cementitious composites (ECC), elastomeric pads embedded into columns, and post-tensioning
were used in three different piers. The bridge model was subjected to two-horizontal components of simulated
earthquake records of the 1994 Northridge earthquake in California. The multiple shake table system at the University
of Nevada, Reno was used for testing. Over 300 channels of data were collected. Test results showed the effectiveness
of post-tensioning and the innovative materials in reducing damage and permanent displacements. The damage was
minimal in plastic hinges with SMA/ECC and those with built in elastomeric pads. Conventional reinforced concrete
plastic hinges were severely damaged due to spalling of concrete and rupture of the longitudinal and transverse
reinforcement. Analytical studies showed close correlation between the results from the OpenSEES model and the
measured data for moderate and strong earthquakes.