Title: Strength, Durability and Shrinkage of High-Strength Rice Husk Ash Concrete

Author(s): H.B. Mahmud, E. Majuar, M.F.M. Zain, and N.B.A.A. Hamid

Publication: Symposium Paper

Volume: 228

Issue:

Appears on pages(s): 189-212

Keywords: chemical resistance; durability; high-strength concrete; initial surface absorption; rice husk ash; shrinkage

DOI: 10.14359/14471

Date: 6/1/2005

Abstract:
This paper reports an investigation on the strength, durability and shrinkage of high strength rice husk ash concrete (HSRHAC) with w/b ratio of 0.27. Rice husk ash (RHA) was incorporated either as 10% ‘addition’ or 10% ‘replacement’ of cement. Specimens were subjected to water curing or air-drying and tested up to 180 days. For comparison purposes, concrete containing 10% condensed silica fume (CSF) and concrete containing superplasticizer alone (SpOPC) were also cast. Results show that with the aid of a polycarboxylic hyperplasticizer, high workability RHA concrete mixtures in the range of 200-250 mm slump and having 28 days strengths of 80 MPa can be routinely produced. In general, strengths of RHA concrete are higher than the control superplasticized concrete but marginally lower than CSF. Durability of concrete with regards to initial surface absorption (ISA) shows that RHA concrete exhibit similar ISA values compared to CSF concrete. After 3 cycles of wetting in magnesium sulphate solution for 30 days followed by 7 days air-drying, RHA concrete produced similar expansion compared to the CSF concrete but lower expansion than the SpOPC concrete. At 180 days, shrinkage of HSRHAC is similar to that of CSF. Based on the current study, it can be concluded that RHA is just as good as CSF in producing high strength concrete of Grade 80. Since RHA can be produced at a much lower cost than CSF, it is an attractive alternative material in the production of HSC.