Usability of diatomaceous earth as a pozzolan in cemenitious systems

USABILITY OF DIATOMACEOUS EARTH AS A POZZOLAN IN CEMENITIOUS SYSTEMS. - (Ph.D. Thesis) Hüseyin Yılmaz ARUNTAŞ GAZI UNIVERSITY INSTITUTE OF SCIENCE AND TECHNOLOGY March 1996 ABSTRACT In this study, the use of two diatomaceous earth from Central Anatolia as pozzolonic additions in cement and mortar was investigated. For this purpose, the physical, chemical and mineralogical properties of the diatomites from Ankara and Çankırı regions were determined first, then they were used 10, 20 and 40 % (by weight of cement) to produce blended cements in two manners: 1) By direct addition to clinker and intergrinding and 2) By replacing some of the cement. Thus, different diatomite replaced cements (DIÇ) and diatomite added cements (DKÇ) were obtained. Various physical and chemical properties of these cements and various mechanical and durability properties of the mortars produced by using these cements were determined. The results were compared with each other as well as with pure PÇ42.5 and KÇ32.5 systems. The pozzolanic reactions of diatomites with CH were followed by XRD methods at 7, 28, and 90 days on 20 % Çankırı diatomite added cement (ÇDKÇ20). The results were compared with PÇ42.5. The physical, chemical and mechanical properties of diatomite added cements (DKÇ) were determined to be in accordance with relevantTurkish standards TS10156, TS26 and TS640. Both diatomites can be used as a pozzolanic material in cements and mortars. 10 and 20 % diatomite added cements (ADKÇ10, ADKÇ20, ÇDKÇ10, and ÇDKÇ20) were found to be appropriate for mortar and concrete production. Science code Key words Page number Adviser : 601.02.02 : Diatomaceaus earth, portland cement, blended cements, pozzolanic materials, hydration, calcium hydroxide, XRD, Water requirement, setting time, strength, shrinkage, sulfate expansion. : 104 : Assoc Prof. Dr. Mustafa TOKYAY