The Influence of size effect on the compressive strength and strain of high strength mortar containing silica fume

Jury : Assoc. Prof. Dr. Cengiz Duran ATİŞAssoc. Prof. Dr. İsmail H. ÇAĞATAYAssoc. Prof. Dr. Alaattin KILIÇAssist. Prof. Dr. A. Hamza TANRIKULUAssist. Prof. Dr. Umur K. SEVİMIn this work, the influence of sample height change and silica fume obtainedfrom Antalya-Etibank Electrometalurgy Factory on the compressive strength ofmortar made with different water-binder and silica fume replacement ratio wereinvestigated. In addition, the influence of the changes in the sample heigth on bothcompressive strength and maximum comressive strain were evaluated. As a resultsof laboratory study carried out, it was seen that, inclusion of silica fume in mortarmixture increased the compressive strength. The increase was maximised between10-20% of silica fume replacement ratio. The increase in the water-binder ratioresults with decrease in compressive strength. It was seen that compressive strengthand compressive strain at strength increased as the sample height-diameter ratioreduced. It was found that compressive strain at strength increased as with thecompressive strength of mortar increased. The reduction in sample height-diameterratio increased compressive strength and compressive strain at strength, however,compressive strain at strength increased more than the increase in compressivestrength. Silica fume mortar behaved more brittle when compared with the controlmortar with equivalent compressive strength. For equivalent compresive strength,mortar made with higher water-binder ratio behaved more ductile when compared tocounterpart mortar made with lower water-binder ratio. The most britlle behaviourwas observed on the mortar made with optimum silica fume replacement (%15)when compared to other replacement ratio.Key Words: Silica fume, compressive strength, mortar, size effect,maximum compressive strain.II