Alkali̇ Si̇li̇ka Reaksi̇yonunun Azaltilmasinda Dört Farkli Mi̇neral Katki Kombi̇nasyonunun Opti̇mi̇sazyonu

Abstract

Presence of alkali silica in aggregates that are used in concrete production causes formation of cracks and decrease of performance over time in concrete.The first damage caused by ASR in Turkey had been observed in certain highway bridges in Izmir locality in 1995. It was found that some aggregates in other regions of Turkey also have a character to cause ASR.The purpose of the study was to minimize potential alkali silica reaction expansion in concrete and mortars produced with the aggregates that are used in constructions in our region.Accelerated mortar bar test method was employed in the study. It was observed in experimental study that that the use of 20-25% fly ash, 25-35% blast furnace slag and 10% silica fume and metakaolin as mineral additive reduced ASR.According to optimization studies, it is appropriate to use 5-10% silica fume, 5% metakaolin, 10-15% blast furnace slag and 10-20% fly ash as mineral additive in optimum mixtures giving ideal expansion value.It was found that the use of 65% of cement together with 35% silica fume, metakaolin, blast furnace slag and fly ash in mineral additive combinations prevents ASR.

Puzolinik malzemelerin (dip külü ve zeolit) tane boyutunun harcın alkali-silika reaksiyonuna ve basınç dayanımına etkisi

“…Ayrıca puzolonların bir diğer faydası da boşlukları doldurarak betonun geçirgenliğini azaltmalarıdır [9]. Puzonilik katkıların ASR'ye etkisi konusunda çalışılan başlıca mineral katkılar uçucu kül [12][13][14][15] silis dumanı (diğer adıyla silika füm) [13][14][15][16], yüksek fırın cürufu [13,15] ve metakaolin [13][14][15]17] olup, bunun yanında tuğla/kiremit tozu [11,12], zeolit [11,[18][19][20], cam tozu [11,21], dip/taban külü [22,23] genleştirilmiş mineral katkılar [24], nano silika [25] vb. ile de çalışmalar yapılmıştır.…”