Effect of Effective Microorganisms (EM) on concrete performance
Abstract
Concrete technology is life-long research. The technology strives to discover the best
additives or admixtures that are able to produce good concrete in terms of physical,
chemical and mechanical properties in a more economical, sustainable, environmental friendly and obtainable. Since admixtures for concrete are known to improve the
properties of concrete and indirectly increase the strength of concrete, they are now
widely used in the construction industry all over the world. Admixtures itself comes with
various types and forms, so intensive studies have been done to improve an applications and functions of admixture. The effective microorganisms (EM) which were invented by
scientist in Japan started to use as admixture for concrete. Thus, this study describes the
analysis of the properties of concrete containing effective microorganisms (EM) as
admixture. This study focuses the effect of different dosages of EM toward strength of
concrete. The compressive strength test was carried out to analyze these properties by
using the concrete cubes with size 100mm x 100mm x 100mm. These concrete mixes
were tested at different ages which are 7, 14 and 28 days. Effective microorganism (EM)
replacement percentages are 5%, 10% and 15% and the strength of concrete with EM
replacement will be compared with the concrete control. All the cubes were cured by
immersed in the water for curing process before the compressive strength tests were
conducted. Some results obtained from the tests shows predictable result. The
experimental results show that 10% EM gives satisfactory results and approaching the
compressive strength test results of the control concrete. This is a very valuable result in
concrete field especially in admixtures application.