Ketahanan Korosi Baja Tulangan dalam Beton menggunakan Palm Oil Fuel Ash (POFA) dan Air Laut

Abstract

POFA (palm oil fuel ash) and seawater have the possible to be used in concrete as an effort to reduce construction costs and environmental waste problems. POFA contains pozzolanic properties such as those contained in cement so it has the possible to be used as a mineral in concrete mixtures. Therefore, the use of POFA and seawater in concrete mixtures have the potential to be implemented, but it is obligatory to pay awareness to the potential for corrosion that also follows. This study aims to evaluate the use of POFA up to 20% as a replacement for cement and the effect of mixing seawater on the strength and corrosion of reinforcing bar in concrete. The compressive strength of concrete was evaluated by carrying out a compressive test on a cylindrical specimen with 100 mm in diameter and 200 mm in height at 7 days and 28 days of age. Furthermore, a concrete cylinder specimen with a diameter of 10 mm reinforcement was used to evaluate the potential for corrosion. Measurement of corrosion estimation using the half-cell potential (HCP) method based on ASTM C876-15. Test results show the use of up to 10% POFA to replace cement by mixing seawater and treated with fresh water has a high strength that is almost the same as normal concrete. The risk of corrosion is also not detected and proven by actual measurements of corrosion. Furthermore, HCP values more negative than -400 mV are predicted to experience corrosion in the reinforcement area above 10%.