Experimental Study on the Seismic Design and Retrofit of Bridge Columns Including211 Axial Load Effects

摘要

This report details the development of retrofit procedures for reinforced211u001econcrete bridge columns and their connections. The report extends the Control and 211u001eRepairability of Damage (CARD) column design philosphy for new structures that 211u001euse replaceable fuse bars in the plastic hing zone for the design of new 211u001estructures (NCEER-97-0013). The work reported resulted in the development of a 211u001enew philosophy, ReCARD (Retrofit, Control and Repairability of Damage) that uses 211u001ethe same fuse-bar concept adopted in CARD designs. Fuse-bars are spliced into 211u001eexisting non-ductile columns that have vulerable hinge zone details. This type of 211u001eretrofit permits relatively rapid and cost-effective repairs following a damaging 211u001eearthquake. Both the CARD and ReCARD details are examined to verify that they 211u001ehave adequate fatigue life under realistic seismic loading, including the effects 211u001eof variable axial loads that arise from a combination of the framing action of 211u001emultiple column pier bents and vertical ground motions.