Investigation of the effect of mineral additives on alkali-silica reaction

In this study, the effects of added mineral additives were investigated in order to minimize shrinkage cracks caused by alkali silica reaction. According to the accelerated mortar rod method (ASTM C 1260), the effects of the quarry aggregate which increases the shrinkage cracks due to the reaction of alkali silica, and the river aggregate which is considered as a harmful and harmless condition, that is considered as potentially harmful,are investigated. For each aggregate used in the experiments, zeolite and silica fume were used by adding different proportions with cement. In the experiments with the aggregate taken from the quarr, zeolite has a ratio of %20, %30 and %50 and silica fume %5,%7,5 and %10ın order to make comparison in the experiments, mineral additives were not added and the experiments were carried out in pure form. In the experimental study, two aggregates obtained from two different regions of Eastern Black Sea Region were used. One of the aggregates was aggregate from Maçka Creek and the other was obtained from quarry in Kömürcüler locality of Yomra. CEM I42.5 R type cement obtained from Aşkale Cement Factory in Trabzon was used in the experiment. The positive effects of zeolite and silica fume, which are two different mineral additives,to the reduction of shrinkage cracks in the reaction with the addition of alkali silica reaction can be seen clearly. As a result, all experiments were carried out in the laboratory of Karadeniz Technical University. As the ratio of zeolite and silica fume from the laboratory increased, shrinkage cracks of the alkali-silica reaction decreased and this is an indication that the reaction was positively affected.