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This paper presents the experimental results of a research program with ceramic block masonry under compression. Four different block geometries were investigated. Two of them had circular hollows with different net area. The third one had two rectangular hollow and the last block was with rectangular hollows and a double central webs. The prisms and walls were built with two mortar type 1:1:6 (I) and 1:0,5:4 (II) (proportions by volume of cement: lime: sand). One:three small scale blocks were used to test block, prisms and walls on compression. It was possible to conclude that the block with double central webs gave better results of compressive strength showing to be more efficient. The mortar didn't influenced the compressive strength of prisms and walls.

The rice in the south of Brazil is one of the main economy activities, which produce a large volume of waste coming from the beneficiation industries. The main goal of this research is evaluate the feasibility of use of rice husk ash, burning on fluidized flow (FF) and sliding grid (SG) for mortars. The characterization methods of rice husk ash (RHA) included loss on ignition, particle size distribution by laser, x-ray diffraction, x-ray fluorescence spectrometer, pozzolanic activity index and specific mass. Mortar specimens were molded with the proportion of 1:3 in mass and water/binder ratio of 0.51. The Portland cement was replaced by RHA with the proportion of 10%, 15% and 20%. Compressive strength, water absorption, air voids content, hydration-releasing heat curves, mercury intrusion porosimetry and scanning electron microscope were performed for all mortars. The mechanical performance of mortar with RHA replacement, shows to be satisfactory and feasible alternative for the final waste disposal.