Properties of fiber reinforced fly ash concrete

ABSTRACTPh. D THESISPROPERTIES OF FIBER REINFORCEDFLY ASH CONCRETEOkan KARAHANDEPARTMENT OF CIVIL ENGINEERINGINSTITUTE OF NATURAL AND APPLIED SCIENCESUNIVERSITY OF ÇUKUROVASupervisor : Assoc. Prof. Dr. Cengiz Duran ATİŞYear : 2006, Pages: 256Jury : Assoc. Prof. Dr. Cengiz Duran ATİŞAssoc. Prof. Dr. Alaettin KILIÇAssoc. Prof. Dr. İsmail H. ÇAĞATAYAssist. Prof. Dr. A.Hamza TANRIKULUAssist. Prof. Dr. Fatih ALTUNIn this study, properties of Sugözü fly ash concrete with polypropylene fiberand steel fiber reinforced normal and fly ash concrete were investigated. Water-binder ratio and the amount of binder were kept constant as 0.35 and 400 kg/m3,respectively. Fly ash replacement ratios were 10%, 15%, 20%, 25%, 30% and 45%.Addition of fiber ratios were 0.05%, 0.10% and 0.20% for polypropylene fiber with19 mm length, and 0.25%, 0.50%, 1.00% and 1.50% for steel fiber with 35 mmlength and 0.55 diameter. Fibers were added to a reference concrete and concretecontaining 15% and 30% fly ash. Test were performed for concrete properties:pozzolanic activity, unit weight, workability, compressive strength, modulus ofelasticity, flexural strength, toughness, splitting tensile strength, abrasion, dryingshrinkage, porosity, water absorption, capillary water absorption, carbonation,ultrasonic velocity and freezing/thawing resistance. Polypropylene fibers wereobserved to have no statistically effects on strength and durability, especiallypolypropylene fiber addition after at 0.05%. Steel fiber positively affected theproperties of concrete such as flexural strength, toughness, splitting tensile strength,abrasion and shrinkage of concretes according to fiber volume. Direct economicfactors caused by energy conversation and the increasing awareness of the need toprotect environment, as well as the modification of certain properties of fresh andhardened concrete were major reasons for using fly ash in fiber reinforced concrete.Test results indicated that Sugözü fly ash could be used as a mineral admixture fornormal and fiber reinforced concrete up to 30% replacement level.Keywords: Polypropylene, Steel Fiber, Fly Ash, Fiber Reinforced ConcreteII