Caracterização tecnológica de quartzitos do estado do Ceará.

Abstract

This paper have as an objective show a technological characterízation, in 20 quartzites samples of various occurrences, of different cities of Ceará State, totalizing 11 localities, from physical-mechanical tests: physical indices (porosity, density and water absorption), bending strength in 3 points, compressive strength, impact resistance and Amsler wear resistance. Due to it has an exotic characteristics, like massive features and a chromatic aspect, the quartzites, has been highlighting in the ornamental rocks sector. The physical-mechanical characterízation of ornamental rocks play an important role in the classification of rock conditions and their purpose. The results of this study were compared with the limit values suggested by the standarts: Associação Brasileira de Normas Técnicas - ABNT - NBR15845:2015 and American Society for Testing Materials - ASTM C 615-11. The presented tests means values ofuniaxial compression strength of 72.24 MPa, flexural strength of 7.11 MPa, apparent absorption of 0.38%, apparent porosity, 0.38%, apparent density, 2774.51 kg/m3, wear in 1000 m of 0.54 cm and hard body impact, from 0.50 m. These quartzites have a very good aesthetic quality, they are resistant, can be used even in civil construction, as coating an internai and externai environments. In flexural strength, only 30% of the samples attended the adopted limits by the specified standards and thus avoid using them in externai locations subject to wind action. Have porosity, considered as average, this parameter did not compromise the resistance of the rock, but it should be avoided to use them in places with prolonged contact with water or any Chemical substance. It is a rock resistant to wear by abrasion, so it can be used in places with great flow of movement such as shopping malls, subway stations, bus stations and airports. The hard body impact, exhibited good resistance to shock, and can be used to coat floors, steps, tables, counters and sinks.