Utilization of Dry Yeast with Distilled Water pH ≥ 8 as An Alternative Material for Concrete Crack Repair Based on Biomaterial

Abstract

This study was conducted to determine the ability of yeast with distilled water solvent at pH 8 to produce calcium carbonate deposits that are used to repair cracks in concrete. Distilled water was used instead of the expensive Tris Buffer solution. The research was conducted using a mixture of glucose, calcium carbonate, and various concentrations of yeast. The concentrations used were 13 g/L, 16 g/L, 19 g/L, 22 g/L, 25 g/L, 28 g/L, 31 g/L, 34 g/L, 37 g/L and 40 g /L, while for calcium acetate monohydrate used as much as 8.1 g, glucose 11.43 g for 32.5 ml of the mixture. The mixture was then deposited for 7 days at a temperature of 30°C so that perfect precipitation would occur. During precipitation, the pH was measured daily to determine the degree of decrease in pH. The greatest decrease in pH was observed in the yeast mixture at a concentration of 40 g/L and water pH of 9.09. From the results of precipitation for 7 days at a temperature of 30oC, it was found that the highest concentration of yeast was 34 g/L with a mixed molarity that could be used were 1.95 mol/L glucose, 1.41 mol/L calcium acetate monohydrate and 34 g/L of yeast.