Long-term deflection and flexural behavior of reinforced concrete beams with recycled aggregate

Abstract

This paper presents experimental results on the long-term deformations of recycled aggregate concrete (RAC) beams for over 1year (380days) and flexural behavior of RAC beams after exposure to sustained loading. Three reinforced concrete (RC) beam specimens were fabricated with replacement percentage of aggregate (100% natural aggregate, 100% recycled coarse aggregate, and 50% recycled fine aggregate) and subjected to sustained loading that is 50% of the nominal flexural capacity. During the sustained loading period (380days), the long-term deflection due to creep and shrinkage was recorded and compared with predicted behavior that was determined based on current specifications (ACI 318 Code). After measuring the long-term deflection for 380days, four-point bending tests were conducted to investigate the flexural behavior of RC beams after exposure to sustained loading and determine any reduction in flexural capacity. A modified equation to predict the long-term deflection values for RC beams with recycled aggregate is proposed, and the experimental results are compared with the predictions calculated using the ACI 318 Code provisions.