Domoaa R Hussein - Department of materials Engineering, Collage of Engineering ,university of Al Mustansiria , Iraq
Mohammed M Salman - Department of civil Engineering, Collage of Engineering ,university of Baghdad , Iraq
Khalid M owaid - Department of chemical Engineering, Collage of Engineering, university of Baghdad, Iraq

The need to produce high performance concrete led the researches to try toexploit the potentialities of natural or artificial materials in order to modifythe performance of concrete in one hand and replacement part of cement byslag. Slag has been used as a substitute of part of cement after beingprocessed, since its main oxides are similar to those of cement. In thisinvestigation, the effect of steel slag was studied including finesses,consistency, initial and final setting time as well as compressive strengthin(7, 28, 90 ) days and absorption of mortar in (7, 28) days wereinvestigated. Results demonstrated that the inclusion of 20% slag as a partialreplacement by cement weight showed superior performance over those ofthe other mixture of steel slag cement, Where the compressive strength after90 days to replacement case (20%) becomes (40MPs ), and the reduction inwater absorption in all cases except at (60%,80%) of replacement.

Portland Cement; Steel Slag; Partial Replacement; Mortar; Compressive Strength