The Effect of Effective Microorganism (EM) Inclusion to the Setting Time of Microbed Cement Paste

Abstract

Abstract. The inclusion of Effective Microorganism (EM) lengthen the setting time of microbed cement paste with respect to the control cement paste. However, the investigation on the influence of EM ingredients to the setting time was not performed yet in the earlier study. Therefore, the test of X-Ray Diffraction (XRD) was performed on the EM product used in order to determine their ingredients. Further examination was carried out to analyse the pore characteristics in examining the effect of the pore size distribution to the setting time of microbed cement paste. Potassium Chloride (KCl) was detected in EM liquid using XRD test. It can be concluded, the ingredient of EM which is consist of the molasses influenced the setting time of microbed cement paste. The hardening rate of microbed cement paste was effected by the presence of KCl. The pore size of microbed cement paste recorded the lower pore volume (mL/g) with respect to the control cement paste. The larger intrusion of mercury was recorded at smaller pore diameter in microbed cement paste while control cement paste occupied at the bigger pore diameter. The microbed cement paste (16.5%) recorded the smaller porosity than cement paste without EM (20.3%). The smaller cement pore effects the delayed setting time of microbed cement.

Microstructure and Strength Properties of Sustainable Concrete Using Effective Microorganisms as a Self-Curing Agent

“…The main purpose of introducing EM in concrete is to produce a new breed of concrete that uses living things with enhanced properties. Better understanding of the impact of bacterial activity on the hydration, chemical phase, and microstructure of cement has enabled researchers to further explore the application of microorganisms in concrete [30]. EM-activated concrete structures are already used in hospitals, schools, apartments, residences, and so forth.…”