01223312

Component

https://doi.org/10.3141/2164-04

http://scholar.google.com...pati&publication_year=2010

Although the benefits of rice husk ash (RHA) as a pozzolan have been known for a long time, its use in concrete has been limited. Past efforts to produce RHA have yielded ashes, some with high carbon content and others with some crystalline silica, neither of which is desirable for use of RHA as a pozzolan. Within the past decade, the production of off-white-colored RHA containing high levels of amorphous silica and very little carbon has become possible through innovations in incineration techniques. Results are presented from a study conducted to ascertain the properties of a low-carbon-content RHA and evaluate it as a supplementary cementing material. In addition, the as-obtained RHA was ground to a smaller particle size to study the effect of finer ash on properties of cementitious mixtures. Specific tests conducted include pozzolanic reactivity and microstructure of RHA and other properties of cementitious pastes and mortars. These include flow, initial and final setting time, compressive strength, flexural strength, and split tensile strength. In addition, other tests such as water absorption, effective porosity, and rapid chloride ion permeability were conducted to ascertain the improvements offered by RHA in enhancing durability of cementitious mixes. Comparative studies were conducted with silica fume mixes. Results from this study are very encouraging and suggest that RHA produced with a consistent quality (i.e., high amorphous silica content and low carbon content) can serve as an environmentally friendly and sustainable supplement for cementitious material needs in future; it can reduce the carbon footprint of concrete.

01223314

10-3430

English

pp 26-35

2010

Transportation Research Record: Journal of the Transportation Research Board

9780309142960

Print

Figures (8) ; References (15) ; Tables (2)

Cement; Compressive strength; Concrete; Durability; Flexural strength; Greenhouse gases; Microstructure; Porosity; Pozzolan; Setting (Concrete)

Amorphous silica; Carbon neutral; Chloride permeability; Rice husk ash; Setting time; Split tensile strength

Highways; Materials; I32: Concrete

TRIS, TRB, ATRI

Nov 9 2010 10:02AM

• Concrete Containing Recycled Concrete Aggregate for Use in Concrete Pavement
• Construction and Performance of Pervious Concrete Overlay at Minnesota Road Research Project
• Cracking Tendency of Bridge Deck Concrete
• Development and Application of Maturity Method for Prediction of Concrete's Resistance to Chloride Ion Penetration
• Development of End-Result Specifications for Concrete in Virginia
• Effects of Soil Clogging and Water Saturation on Freeze–Thaw Durability of Pervious Concrete
• Engineered Cementitious Composites: Can Composites Be Accepted as Crack-Free Concrete?
• Evaluating the Use of Recycled Concrete Aggregate in Pervious Concrete Pavement
• Evaluation of Environmental Effectiveness of Titanium Dioxide Photocatalyst Coating for Concrete Pavement
• Evaluation of Time of Set for Concrete Mix in Cold Weather with HIPERPAV Wisconsin Model
• Grid Types Used to Strengthen Reinforced Concrete Panels Subjected to Impact Loading
• Interlaboratory Study on Measuring Coefficient of Thermal Expansion of Concrete
• Microstructural and Mineralogical Characterization of Cement Kiln Dust–Activated Fly Ash Binder
• New AASHTO T336-09 Coefficient of Thermal Expansion Test Method: How Will It Affect You?
• Porous Concrete Pavements: Mechanical and Hydraulic Properties
• Resistance of Portland Cement Pervious Concrete to Deicing Chemicals