CARBON NANOFIBER AGGREGATE-BASED STUDY ON STRUCTURAL BEHAVIOR OF REINFORCED CONCRETE COLUMNS

Past studies have demonstrated that carbon nanofiber aggregate (CNFA) to be self-sensing and can be embedded in concrete structures to monitor the strain due to external loading. In this study, CNFAs were embedded in 16 reinforced concrete columns governed by flexure or shear failures for the purpose of the structural health monitoring. The columns were excited by cyclic loads with various loading rates to study the effect of strain rate on the structural behavior of reinforced concrete columns. Finite element analysis program OpenSees was used for comparison with the test results. The test results showed that the CNFAs were capable of sensing complex strain histories in qualitative way and the loading rates in the range of 0.05 Hz to 7 Hz did not have significantly influence on the structural behavior of the columns. The analytical hysteresis loops are in agreement with the test outcomes.