THE JOURNAL OF KMUTNB

Volume 32, No. 02, Month APRIL, Year 2022, Pages 366 - 374

Threshold total chloride content, depassivation time of reinforcing steel, and compressive strength of concrete with fly ash and partial replacement of fine aggregate by bottom

Sira Arttamart, Taweechai Sumranwanich

Abstract Download PDF

This paper aims to study threshold total chloride content, depassivation time of reinforcing steel and compressive strength of concrete with fly ash and bottom ash as partial replacement of fine aggregate. Ordinary Portland cement was used as a main cementitious material. The ratio of fly ash for replacement cementitious materials was 0.30 and the replacement ratio of fine aggregates by bottom ash was 0.10, 0.20, and 0.30. The slump of fresh concretes was controlled at 10 ± 1 centimeter. Specimens were cured in tap water or air until 28 days before starting the test in order to study the influence of curing type. From the experiment results, it was found that concrete mixed with 30% replacement of binder by fly ash and 10% replacement of fine aggregate by bottom ash had the highest threshold total chloride content and the longest depassivation time of reinforcing steel. Moreover, it was found that concrete containing 10% replacement of fine aggregate by bottom ash had the highest compressive strength at 28 days. Concretes cured in water had higher threshold total chloride content, depassivation time and compressive strength than concretes cured in air.

Keywords

Threshold Total Chloride Content; Depassivation Time; Concrete; Reinforcing Steel; Fly Ash; Bottom Ash

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