Shaking-Table Testing of High Energy–Dissipating Rubberized Concrete Columns

This paper presents the results of the first shake-table tests of a large-scale rubberized concrete column. The rubberized column was formed by replacing 20% of the volume of fine aggregate with crumb rubber. The response of the rubberized column was compared to that of a conventional bridge column. Both columns had the same construction details, and the only difference was the material used. Both columns were subjected to a sequence of scaled historical ground motion recorded in the Northridge-01 1994 earthquake with near-fault pulse-like characteristics. The conventional column formed a flexural plastic hinge with rebar fracture after 14 scaled test runs, corresponding to 140% of the design earthquake. The rubberized column experienced the rebar fracture after 19 test runs, corresponding to 190% of the design earthquake. The rubberized column achieved a strength that was only 3% lower than that of the conventional column. Moreover, the rubberized column displayed a 12.5% increase in the lateral drift capacity. The dissipated energy of the rubberized column increased by 16.5% compared with the conventional column.