Ultrasound and mechanical tests combined with ANOVA to evaluate brick quality

Mixtures of clays are often used in the manufacture of bricks, with distinc t additives for diverse ends. The firing process, however, determines the f inal properties of the material. In this work, ultrasound and mechanical te sts have been combined with a statistical tool, the analysis of variance (A NOVA), to analyse the mineralogical and physical characteristics of solid b ricks manufactured from mixtures of local clays to which small amounts of a dditives have been included. They were then fired at different temperatures , ranging from 850 up to 1100 degreesC. A new parameter, defined as the "re sistance anisotropy" has been formulated to simplify the statistical interp retations. In addition, a two-way ANOVA interaction analysis has been used to evaluate the effect that selected factors (addition/absence of additives and firing temperature) have on the technical quality of bricks. (C) 2001 Elsevier Science Ltd and Techna S.r.l. All rights reserved.