Investigating the Effects of Acid Treatment on the Mechanical and Durability Properties of Concrete containing Rice Husk Ash

Utilization of pozzolanic materials is one of the strategies applied to reduce pollution emitted during cement production. In this regard, rice husk ash produced through controlled incineration shows high pozzolanic performance which causes reasonable improvement in mechanical and durability properties of concrete materials. Moreover, acid treatment before incineration process is one of the most effective methods which is attracted less attention.
According to the above mentioned issues, in the current study, the influence of acid treated rice husk ash on mechanical and durability characteristics of concrete was investigated. In addition, to make an exact comparison, concrete mixtures incorporating untreated rice husk ash, zeolite, and silica fume were fabricated and tested. Testing program includes compressive strength, water penetration under pressure, electrical resistivity, half-cell potential, and rapid chloride permeability tests.
Results indicated that acid treated rice husk ash performed much better than untreated one and zeolite in increasing compressive strength and durability indices. Moreover, concrete containing silica fume had higher durability compared to concrete incorporating treated rice husk ash; however, the influence of treated rice husk ash on compressive strength was very similar to silica fume.