Influence of Powerplant Biomass Ash on Hydration Heat and Shrinkage of Self-Compacting Concrete

This research presentedthe study of heat of hydration and autogenous shrinkage of self-compacting concrete containing unground biomass ash. In the experiment, the unground biomass ash was used to replaced ordinary Portland cement at the ratio of 0, 10, and 20 percent by weight of total binder (500 kgm3⁄). The investigated concrete properties included water to powder ratio (w/p), slump flow time to 500mm(t500), temperature induced by hydration reaction, and autogenous shrinkage of the concrete. The results revealed that, at the same flow spread, an increase of biomass ash replacement ratio resulted in a linear increase of water to powder ratio (w/p) and a decrease of t500, maximum concrete temperature, and autogenous shrinkage strain of concrete. These results indicate that the use of unground biomass ash in self-compacting concrete can reduce the internal temperature and the autogenous shrinkage, which are the cause of early age cracking.