Use of Rice Husk-Bark Ash in Producing Self-Compacting Concrete

This paper presents the use of blend of Portland cement with rice husk-bark ash in producing self-compacting concrete (SCC). CT was partially replaced with ground rice husk-bark ash (GRHBA) at the dosage levels of 0%–40% by weight of binder. Compressive strength, porosity, chloride penetration, and corrosion of SCC were determined. Test results reveal that the resistance to chloride penetration of concrete improves substantially with partial replacement of CT with a blend of GRHBA and the improvement increases with an increase in the replacement level. The corrosion resistances of SCC were better than the CT concrete. In addition, test results indicated that the reduction in porosity was associated with the increase in compressive strength. The porosity is a significant factor as it affects directly the durability of the SCC. This work is suggested that the GHRBA is effective for producing SCC with 30% of GHRBA replacement level. 1. Introduction Self-compacting concrete (SCC) is featured in its fresh state by high workability and rheological stability. SCC has excellent applicability for elements with complicated shapes and congested reinforcement [1]. In concrete materials, most of the previous works studied the effects of pozzolanic materials on physical and mechanical properties of normal concrete. The pozzolanic materials such as fly ash, rice husk ash, palm oil fuel ash, bagasse ash, and rice husk-bark ash are used in the production of concrete instead of using the cement only [2–6]. In Thailand, rice husk-bark ash is a residue obtained from the burning of rice husk-bark as fuel source in the small power generation plants (Thai Power Supply Company Ltd., in Chachoengsao Province). Two portions of rice husk and one portion of eucalyptus bark are the normal composition and it is burnt at 800–900°C [7]. The landfills of rice husk-bark ash are still the problem of power generation plants because this waste ash is currently not useful for any works. There are few researches about the rice husk-bark ash characteristics and its mechanical properties relating to the normal concrete work. Therefore, the purpose of this research is to utilize the rice husk-bark ash as pozzolanic material for partly replacing Portland cement in order to produce self-compacting concrete (SCC) as well as reduce negative environmental effects and landfill volume, which is required for eliminating the waste of ash. 2. Materials and Experiment Details 2.1. Materials Portland cement type I (CT) and rice husk-bark ash (from Thai Power Supply Company Ltd., in Chachoengsao Province,