In the studies of plastic clays for use in structural clay products is usual the determination of the mineralogicals characteristcs by DTA and plasticity through the Atterberg limits. The conventional method utilized for determination of the LL, LP and IP requires much attention. In the specific case of the ceramic technology for moulding hole bricks by extrusion, not many data have been reported. The purpose of this work is to study the mineralogy of 15 specimens of plastics clays used in the structural clay products industry in Paraíba State, by DTA method, as well as their plasticity limits using the Atterberg limits by Casagrande method and cone penetration test. The results show that the mineralogical composition is recent quaternary kaolinite clays with LP varying from 15.42% to 36.72%, LL from 24.70% to 71.00% and IP from 6.82% to 34.28% by Casagrande method and LP from 6.60% to 47.70%, LL from 26.50% to 71.60% and IP from 4.00% to 47.70% by cone penetration test, that are the plasticity limits recommended to be used for plastic clays in structural clay industry.
structural clay products; mineralogy; plasticity
