Utilization of Natural Anhydrite as Concrete Component

Abstract

In this study, the physicomechanical properties of concrete samples produced by adding of micronized natural anhydrite (CaSO4) in various proportions to the concrete mix were evaluated. The natural anhydrite used as raw materials and the crushed stone aggregate were derived from Zeyvegediği anhydrite formation outcropped in Ulukışla (Niğde) region and Karaisalı formation (L. Miocene)’s limestone in Karaisalı (Adana) region, respectively. The compressive strength and ultrasonic velocity (UPV) tests were conducted on the concrete specimens prepared.The test results indicate that the concrete strength reaches maximum values quite close to each other at the micronized natural anhydrite content range of 27-42% in the concrete mix. On the other hand, the strength decreases dramatically outside of this range (27-42%) of anhydrite content in concrete mix.Analysis of the relationship between ultrasonic velocity values and saturated densities of the concrete specimens exhibits a strong negative correlation. This extraordinary statement is due to smaller UPV value of natural anhydrite having specific gravity of 2.96 than that of limestone used as crushed aggregate having specific gravity of 2.72.The results shows that natural anhydrite micronized provides binding behavior like cement in concrete, and pronounced strength increase in case of using in particular proportions.

Özet

Bu çalışmada, doğal anhidrit (CaSO4)’in beton karışımına değişik oranlarda eklenmesi ile oluşturulan beton örneklerinin fizikomekanik özellikleri değerlendirilmiştir. Hammadde olarak kullanılan doğal anhidrit Ulukışla (Niğde) bölgesinde yüzeyleyen Zeyvegediği anhidritinden; kırmataş agregası Karaisalı formasyonu (A. Miyosen) kireçtaşlarından derlenmiştir. Hazırlanan beton örnekleri tek eksenli basınç dayanımı ve ultrases hız deneylerine tabi tutulmuştur.