Document Type : Original Research Paper

Authors

1 PhD. Student, Faculty of Earth Sciences, Shahid Beheshti University, Tehran, Iran

2 Associate Professor, Faculty of Science, Shahid Beheshti University, Tehran, Iran

3 Associate Professor, Faculty of Science, Kharazmi University; Building and Housing Research Center, Tehran, Iran

4 Assistant Professor, Building and Housing Research Center, Tehran, Iran

5 Master of Science, Building and Housing Research Center, Tehran, Iran

Abstract

In the north of Abyek - Qazvinmain road, various volcanic units contain olivine basalt, basalt, andesitic basalt, dacite, andesite and their associated tuffs with Eocene to Quaternary age are exposed. In order to examine geochemical and petrographic features effect on pozzolan activity, five samples of different rocks in the area crushed and analysed by thermogravimetric method in Housing and BuildingResearchCenter. Unweathered glassy tuff s with 26.83% pozzolanic activity ranked as good quality pozzolan. Relatively weathered tuffs and dacite present pozzolanic activities in the range of 21 to 24 % and are medium quality pozzolan. Lithic tuffs with 19.70% pozzolanic activity are in the weak quality pozzolan category. Generally, tuffs and dacits with no alteration and glass in their matrix are suitable alternatives to use as pozzolane in mix cement and lithic bearing tuffs with weathering are poor in pozzolanic features and are not recommended to be used in cement composition.

Keywords

References
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