American Journal of Mechanical and Materials Engineering
Volume 1, Issue 3, September 2017, Pages: 78-82
Received: May 4, 2017;
Accepted: May 18, 2017;
Published: Jul. 13, 2017
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Kwabena Appiah Boakye, Building Materials Development Division, CSIR-Building and Road Research Institute, Kumasi, Ghana
Albert Amartey Adjaottor, Department of Materials Engineering, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
Trinity Ama Tagbor, Building Materials Development Division, CSIR-Building and Road Research Institute, Kumasi, Ghana
Delali Adjei, Building Materials Development Division, CSIR-Building and Road Research Institute, Kumasi, Ghana
Calcined clay pozzolan, the major mineral admixture used in Ghana to partially substitute ordinary Portland cement has gained massive recognition in the local construction industry because of its technical advantages and affordability. The most prominent undesirable property associated with the use of calcined clay pozzolans is slow setting and strength development, especially at early ages. This paper presents a study of the effect of Na2SO4 on the mechanical properties of high volume pozzolan cements. The cements containing 30 wt. %, 40 wt. %, 50 wt. % and 60 wt. % calcined clay pozzolan was activated with 1%, 2%, 3% and 4% Na2SO4. Some physical properties such as Blaine index, specific gravity, water demand and setting times were determined. The chemical compositions of the blended cements were also analyzed. The effect of Na2SO4 on compressive strength of blended cements was determined after 2, 7, 28 and 180 days. Durability studies on activated blended cements in aggressive media were also conducted. Activation with a minimum of 2% Na2SO4 improved the 2 days compressive strength of cement containing 60% calcined clay pozzolan by 66.2% and caused it to behave as Class 32.5N cement, at 28 days. As Na2SO4 dosage increased, compressive strength also increased. The optimum Na2SO4 dosage was 2%. Activated blended cements resisted MgSO4 environment better than unactivated cements
Kwabena Appiah Boakye,
Albert Amartey Adjaottor,
Trinity Ama Tagbor,
Influence of Na2SO4 on the Mechanical Properties of High Volume Calcined Clay Pozzolan Cement, American Journal of Mechanical and Materials Engineering.
Vol. 1, No. 3,
2017, pp. 78-82.
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