Study of alternative materials for Portland cement replacement in civil construction

Abstract

The proposal of this work is to study materials, which initially were classified as disposable, in building construction as new alternative materials. In this way, this research studied the partial replacement of Portland cement in mortars by the following pozzolans: sugar cane bagasse ash (SCBA), rice husk ash (RHA), metakaolin (MK) and silica fume (SA). Theses composites were compared with a control mixture, which no Portland cement replacement, in the following tests: compressive strength, consistency, water capillarity and water immersion.   The replacements percentages carried out were 5, 10, 15, 20, 25 and 30% for SCBA, RHA and metakaolin, and 5, 10 and 15% for silica fume by weight. The compressive strength test was performed at curing times of 3, 7, 28 and 90 days, whereas water capillarity and water immersion were carried out at 28 days. In the early ages, few mixtures showed resistance above the reference, but with 90 days, six mixtures passed the control. All mixtures with pozzolans presented less water absorption by immersion and capillarity. Sustainably, the use of SCBA, RHA, MK and SA is viable.