| Popis: |
Ferrochrome slag (FCS), an industrial solid waste, has promising properties that promote its use as an alternative aggregate in concrete production. This can be a partial solution to reduce the pressure on natural aggregates. This study experimentally studied the effect of FCS fine aggregate on the physical and mechanical behavior of concrete-filled steel tube (CFST) stub columns exposed to different temperatures. The influence of FCS fine aggregate substitution level and heating temperature range (200°C, 400°C, 600°C, and 800°C) on load-displacement behavior, ultimate load, and failure mode was investigated. The CFST stub columns were filled with three different concrete mixes using conventional fine aggregate, 50% and 100% FCS as a fine aggregate replacement. The results showed that increasing the FCS fine aggregate content in the concrete increased the ultimate strength and stiffness of CFST stub columns at both ambient and after being exposed to elevated temperatures. The fine natural aggregate can be fully replaced by the FCS fine aggregate without compromising any mechanical properties of concrete, as well as CFST columns at room and elevated temperatures. The Eurocode 4 (EC4) and ACI codes show a conservative prediction of ultimate strengths for the CFST stub columns at ambient as well as at elevated temperatures compared to the experimental results for all three concrete mixes. However, EC4 gives a closer estimation of the ultimate load for all concrete mixes than the ACI recommendation. |
