Mechanical Properties and Durability of High Strength Concrete Containing Rice Husk Ash
H. B. Mahmud, E. Majuar, M. F. M. Zain, and N. B. A. A. Hamid
Appears on pages(s):
durability; flowing concrete; high strength; mechanical properties; rice husk ash
This paper reports an investigation on the mechanical properties and durability of high strength concrete containing rice husk ash (RHA). Mixtures containing 10% RHA by weight of cement and w/cm of 0.27 were cast. RHA was incorporated either as an admixture or as cement replacement material. A superplasticizing admixture was used to provide flowing characteristics. Results on the workability, mechanical properties and initial surface absorption (ISA) test are reported. The specimens were subjected to water and air-drying conditions and tests on the specimens were carried out up to 180 days. By applying a superplasticizer based on polycarboxylic ether, workability of RHA concrete in the range of 200—250 mm slump can be attained. This type of concrete can achieve high strength of 80 N/mm2 at 28 days, irrespective of method of inclusion of rice husk ash or curing conditions. Compared to condensed silica fume (CSF) concrete at similar w/cm and workability, the strength of RHA concrete is about 6% lower. In general, the mechanical properties of RHA concrete are higher than the control super-plasticized concrete but marginally lower than the CSF concrete. Durability of RHA concrete with regards to ISA is similar or better than CSF concrete.