Based on the number of tests conducted, the following conclusions were reached;
The initial and final setting times of cement were determined to be 122 minutes and 3hours 3 minutes respectively, also the soundness of the cement was observed to be 4.2mm.
The Aggregate Crushing Value (ACV), Aggregate Impact value (AIV), Specific Gravity of coarse aggregate (SG), specific gravity of fine aggregate (SG) were obtained as 20.50%
(ACV), 16.70% (AIV), 2.70 (SG coarse) and 2.65 (SG fine aggregate) respectively.
The RHA used in this research work is a pozzolana and conforms to the ASTM C618 requirement which has great potential use in concrete.
The value for the required properties of bitumen as a binder as regards its penetration, viscosity, flash and fire point, durability and solubility are 80/100 penetration grade, 138mm³/s viscosity, 240˚C and 259˚C flash and fire point, 100cm ductility, and 99%
solubility which all conform with those specified in ASTM standard specification of the design of asphalt concrete.
The trial mix obtained using 10.0% RHA and 90% OPC meets the standard specified in terms of stability, flow, VIM, and VMA, at an optimum bitumen content of 5.5%.
5.2 Recommendation
It is important that engineers and material scientists understand the basic principles behind pozzolanas, so as to provide solutions to constructional problems.
In this study, one rice husk sample was used for the experiment. Future studies should use more than one sample from various sources. It is important to study the different behaviours of RHA in asphalt concrete from different rice husk, to look into the performance contingency of the samples.
Mechanical properties such as tensile strength, flexural strength, and elastic modulus should be investigated in future research, as this will widen the application of RHA in asphalt concrete.
While determining mechanical properties of asphalt concrete using Marshall Stability method, crushing should be done immediately after curing, while cubes temperature is still high, and the samples are still wet, as doing otherwise could lead to variation in results.
REFERENCE
Adylov, G.Y., Kulagina, .N.A., Mansurova, E.P., Remi, M.k. and Faiziev, S.A. (2005):
lightweight Dinas Refractories Based on Rice Husk Ash Refractories and Industrial ceramics: 46(3): pp.187 – 188.
Ahmed, I. and Lovell, C. W. (2003): Rubber Soils as lightweight geomaterials.
Anwar, M., Miyagawa, T., and Gaweesh, M. (2001): Using rice husk ash as a cement replacement material in concrete: In the Proceedings Of the 2001 First International Ecological Building Structure Conference: pp. 671- 684.
Aziz, M.A.E., Aleem, S.A.E., Heikal, M. Didamony H.E. (2005): Hydration and durability of sulphate-resisting and slag cement blends in Caron’s Lake water: Cement and Concrete Research. 35(8): 1592– 1600.
Bhanumathidas N. and Mehta, P. K. (2004): Concrete Mixtures Made with Tenary Blended Cements Containing Fly Ash and Rice Husk Ash in: malhota VM, editor. In the proceedings of 2004 seventh CANMENT international conference: pp. 379- 391.
Chaiyasena, T. (1992): A Study of Properties of High Concrete Made from Portland cement Containing Rice Husk Ash, Fly Ash And Superplasticizer: M.sc. Eng. Thesis, Khon Kaen University Thailand.
Chindaprasirt, P., Jaturapitakkul, C., and Sinsiri, T. (2005): Effect of Fly Ash Fineness on Compressive Strength and Pore Size of Blended Cement Paste: Cement and Concrete Composites: 27(4): pp. 425–428.
Chindaprasirta, P., Kanchandaa, P., Sathonsaowaphaka, A., and Caob, H.T. (2007): Sulfate resistance of blended cements containing fly ash and rice husk ash: Construction and Building Materials. 21(6): pp. 1356-1361.
Confidential Report (1998): Rice Husk Ash Market Assessment Bangkok, Thailand.
CORUS (2002) www.corusgroup.com
Coutinho, J.S. (2002): The Combined Benefits of CPF and RHA in Improving the Durability of Concrete Structures: Cement and Concrete Composites: 25(1): pp. 51-59.
Dabai, M. U., Muhammad, C., Bagudo, B. U. and Musa, A. (2002): Studies On the Effect of Rice Husk Ash as Cement Admixture: pp. 252-256.
Dakroury, A.E., and Gasser, M.S. (2008): Rice husk ash (RHA) as cement admixture for immobilization of liquid radioactive waste at different temperatures: Journal of Nuclear Materials. 381(3): pp. 271–277.
Farraro, R., Nanni, A., Vampati, R. and Matta, F. (2010): Carbon Neutral off- white Rice Husk Ash as Partial White cement Replacement: pp 1078- 1083.
Feng, Q., Yamamichi, H., Shoya, M., and Sugita, S. (2004): Study on the Pozzolanic Properties of Rice Husk Ash by Hydrochloric Acid Pretreatment. Cement and Concrete Research: 34(3): pp. 521–526.
Ganesan, K., Rajagopal, K., and Thangavel, K. (2008): Rice Husk Ash Blended Cement:
Assessment of Optimal Level of Replacement for Strength and Permeability Properties of Concrete: Construction and Building Materials: 22(8): pp. 1675–1683.
Gidde, M.R. and Jivani, A.P. (2007): Waste to Wealth- Potential of rice husk in India a literature Review: Proceedings of the International Conference on Cleaner Technologies and Environmental Management PEC, Pondicherry: India: January 4-6 2007: Pp 586-590.
Griffiths, G. and Thom, N. (2011): Pavement Design Guide.
Habeeb, G.A., and Fayyadh, M.M. (2009): Rice Husk Ash Concrete: the Effect of RHA Average Particle Size on Mechanical Properties and Drying Shrinkage:
Australian Journal of Basic and Applied Sciences: 3(3): pp. 1616-1622.
Habeeb, G. A. and Mahmud, H. B. (2010): study on properties of rice husk ash and its use as cement replacement material: Pp. 1160- 1173.
Harold W. (2002): Personal Communication, CORUS Teeside Technology Centre.
Hewlett, P.C. (1998): Chemistry of Cement and Concrete, Wiley, New York. pp. 471–601.
Ismaila, M.S., and Waliuddin, A. M. (1996): Effect of Rice Husk Ash on High Strength Concrete: Construction and Building Materials: 10(7): pp. 521-526.
Jeffrey, C. R., Alferg, B. L., Gerald, P. M. (2002): Rice Husk Ash and Palm Oil Fiber:
Potential filler for Stone Mastic Asphalt 10: Agusan del Sur National Science High School, Government Centre, Prosperidal, Agusan dul Sur.
Jiang, L.H., and Malhotra, V.M. (2000): Reduction in Water Demand of Non Air-Entrained Concrete Incorporating Large Volume of Fly Ash. Cement and Concrete Research:
30(11): pp. 1785-1789.
Kandhal, S. P. and Khatri A. M. (2002): Relating Asphalt Absorption to Properties of Asphalt Cement and Aggregate.
Lertsatitthanakorn, C., Atthajariyakul, S., and Soponronnarit, S. (2009): Techno-economical evaluation of a rice husk ash (RHA) based sand–cement block for reducing solar conduction heat gain to a building: Construction and Building Materials. 23(1): pp.
364–369.
Mahmud, H.B., Hamid, N.B.A.A., and Chia, B.S. (1996): High Strength Rice Husk Ash – A preliminary Investigation. In the Proceedings of the 1996 3rd Asia Pacific Conferences on Structural Engineering and Construction: pp. 383-389.
Mahmud, H.B., Majuar, E., Zain, M.F.M., and Hamid, N.B.A.A. (2009): Mechanical Properties and Durability of High Strength Concrete Containing Rice Husk Ash.
Journal of advanced concrete technology: 79(1): 21-30.
Merrian Webster online Dictionary and thesaurus, 2013
Mehta, P.K. (2002): Rice Husk Ash - A unique supplementary cementing material Proceeding International Symposium on Advances in Concrete Technology: Editor:
Malhotra,V.M. Athens, Greece, pp. 407- 430.
Mehta, P.K. (2004): High performance, high volume fly ash concrete for sustainable development. In: Proceedings of the International Workshop on Sustainable Development and Concrete Technology, University of California, Berkeley, USA.
Mostafa, N.Y., and Brown, P.W. (2005): Heat of Hydration of High Reactive Pozzolans in Blended Cements: Isothermal Conduction Calorimetry. Thermochimica Acta: 435(2):
pp. 162–167.
Muga, H., Betz K., Walter J., Pranger C., Vidor A. (2005): Development of Appropriate and Sustainable Construction Materials: Civil and Environmental Engineering Sustainable Futures Institute, Michigan Technology University.
Musa, A., Dabai, M.U., Muhammad, C. and Bagudo, B.U. (2010): Studies on the Effect of Rice Husk Ash as Cement Admixture: Nigerian Journal of Basic and Applied Science
(2009), 17(2). Pp 252-256.
NAPA Special Report 152, (2001): Evaluation of Rice Hull as a Lignocellulosic Substitute in PCC Mixtures.
Neuwald, A. D (2010): National Precast Concrete Association: Precast Magazines: Archive:
2004 – 2008: Supplementary Cementitious Materials.
Nicole, P.H., Monteiro, P.J.M., and Carasek, H. (2000): Effect of Silica Fume and Rice Husk Ash on Alkali-Silica Reaction: Materials Journal: 97(4): 486-492.
Omatola K.M (2009): Instrumental Analysis of Rice Husk Ash: Unpublished M.Sc. Thesis:
Department of Physics, University of Agriculture, Makurdi, Nigeria.
Owen, P.L. (1979). Fly Ash and Its Usage in Concrete: Journal of Concrete Society: 13(7):
pp. 21-26.
Oyetola, E.B and Abdullahi, M. (2006): The use of Rice Husk Ash in Low- Cost Sand Crete Block production. Department of Civil Engineering, Federal University of Technology, P.M.B.65, Minna, Nigeria: Pp. 58-70.
Papadakis, A. L. et al (2009): Pozzolanic characteristics of a natural Raw material for use in blended cement: Vol.33, No. B4, pp. 291-300.
Rice Husk Ash Market Study (2003): ETSU U/00/00061/REP.
Rodriguez, G.S. (2006): Strength Development of Concrete with Rice-Husk Ash: Cement and Concrete Composites: 28(2): pp. 158-160.
Sakr, K. (2006): Effects of Silica Fume and Rice Husk Ash on the Properties of Heavy Weight Concrete: Journal of materials in civil engineering. 18 (3): pp.367-376.
Saraswathy, V., and Ha-Won, S. (2007): Corrosion Performance of Rice Husk Ash Blended Concrete: Construction and Building Materials: 21 (8): pp. 1779–1784.
Sata, V., Jaturapitakkul, C., Kiattikomol, K. (2007): Influence of Pozzolan from Various By-Product Materials on Mechanical Properties of High-Strength Concrete. Construction and Building Materials: 21(7): pp. 1589–1598.
Rice hulls could nourish Silicon Valley (1994): Science News, Vol.57 (11): Pp 194.
Siddique, F. (2008): Waste materials and by-products in concrete: with 174 tables: Springer Press.
Siriwandena, S., Ismail, H. and Ishakiaku U.S. (2001): A comparison of white rice husk ash and silica as fillers in Ethylene-Propylene-dience terpolymer Vulcanizates: Polymer International Vol. 50 (6): Pp 707- 713.
Smith, R.G. and Kamwanja, G.A. (1986): The Use of Rice Husk for Making a Cementitious Material, Proc. Joint Symposium on the Use of Vegetable Plants and their Fibers as Building Material, Baghdad.
Tashima, M.M., Silva, C.A.R., Akasaki, J.L., and Barbosa, M.B. (2004): The Possibility of Adding the Rice Husk Ash (RHA) to the Concrete: In the Proceedings of the 2004 International RILEM Conference on the Use of Recycled Materials in Building and Structures: pp. 778 – 786.
Tuts, R. (1994). Rice husk ash Cement project in Kenya. BASIN News: Vol. 7, pp 17 -21.
Washington Asphalt Pavement Association (WAPA): 2010.
Watkinson, H. (2002): personal communication, CORUS Teeside Technology Centre.
White, D. T., Johnson, S. R., Yzenas, J. J. and Griffith, J. R. (2011): Aggregate Contribution to Hot Mix Asphalt (HMA) performance, pp 200 – 220.
Yu, Q., Sawayama, K., Sugita, S., Shoya, M., and Isojima, Y. (1999): The reaction between rice husk ash and Ca(OH)2 solution and the nature of its product: Cement and Concrete Research. 29(1): 37–43.
Zhang, M.H., Lastra, R., and Malhotra, V.M. 1996: Rice husk ash paste and concrete: Some aspects of hydration and the microstructure of the interfacial zone between the aggregate and paste. Cement and Concrete Research: 26(6): 963-977.