moisture expansion (me) phenomenon results from the action of water and water vapors causing the expansion of ceramic materials, which may damage the material damage and jeopardize its useful life. in literature there is much emphasis on problems generated by the me and the tensions resulting from this expansion, but until now there is a lack of data on mechanical behavior of ceramics after me. recent works in ufcg specifically deal with this problem in ceramic bricks. initially it was found that in the case of ceramic bodies for use in red ceramic burned at different temperatures, ranging from 700 to 1100 oc with me induced by soaking, boiling and autoclaving, the me correlated with the mechanical behavior of burned bodies, and a reduction in modulus of rupture with the rising of me was observed. researches undertaken with compositions developed using clay and calcium carbonate and magnesium carbonate as adds for red ceramic, burned from 850 to 1000 °c, showed the beneficial effect of calcium carbonate in reducing moisture expansion and rise modulus of rupture. correlations between me and modulus of rupture, was observed when calcium carbonate was used as additive. however, this associations was noted when magnesium carbonate was used as additive. works carried out using fine quartz as additive of red ceramic compositions and aiming glassy phases development not observed well defined correlations between me and modulus of rupture. the addition of 10 and 20% of fine quartz improve the mechanical strength of ceramic bodies after autoclaving and that the addition of 30% of quartz decreases its mechanical strength.