Engineering properties of blended concrete with Colombian rice husk ash and metakaolin

Abstract

The  effects  of  partial  replacements  of  Portland  cement  by  Metakaolin  (MK)  and  Rice  Husk  Ash  (RHA)  on  the  mechanical and durability properties of concrete mixtures were investigated. Two types of RHA –thermal (TRHA) and chemical treated (ChRHA)- and a sample of MK, at different percentages of replacement by weight, were studied. MK was produced by heat treatment (700 °C for 2 hours) of a Colombian kaolin. The properties of the investigated concrete include compressive strength and durability. The durability aspects tested were: water absorption, chloride ion penetration, carbonation and sulfate resistance. The results were compared with those of cementitious materials without  the  pozzolanic  admixtures  and  with  addition  of  Silica  Fume  (SF).  It  was  noted,in  general  an  enhanced  performance  on  the  mechanical  and  durability  properties  of  the  concretes,  proving  the  feasibility  of  its  rational  utilization in engineering as supplementary cementing materials for environmental sustainability.