Long-Term Prestress Loss and Camber of Box Girder Bridge

Abstract

This paper presents results regarding the effect of elevated temperature (ET) curing on the compressive strength and electrical resistivity of concrete with slow-reacting supplementary cementitious materials (SCMs). Concrete mixtures with Class F fly ash (FA), ground-granulated blast furnace slag (GGBS), or both were tested. Elevated temperature (ET) curing (in a 36°C [97°F] lime water bath) and room temperature (RT) curing (in a 21°C [70°F] lime water bath) with different durations were investigated. Test results show that the ET curing method can be employed to achieve the specified 28-day compressive strength and resistivity values on concrete with slow-reacting SCMs without compromising the long-term strength and resistivity properties. It is also shown that the use of granite as coarse aggregate as an alternative to limestone can increase concrete’s electrical resistivity but has a modest adverse effect on the compressive strength of not fully hydrated concrete.