Indexing
All Issues
Submission
Author Guidelines
Reviewers
Editorial Members
Publication Fee
Vol.5 , No. 1, Publication Date: Jan. 11, 2018, Page: 7-16
, California Bearing Ratio (CBR), American Association of State Highway Officials (AASHTO) and Asphalt Institute design methods has a great potential on the cost effectiveness in pavement development. The aim of the research is to compare different structural methods of flexible pavement analysis and design on the basis of cost and long lasting serviceable structure. Traffic volume count was carried out manually, while soil samples collected from selected locations were tested to determine the parameters to be used for the structural design using both empirical and mechanistic- empirical methods. Average GI of 4 was obtained for the subgrade. The soaked CBR of 13% was determined and used for the design of a pavement structure to support a total Equivalent Single Axle Load (ESAL) of 5.5x10<sup>6</sup> AADT traffic for a design period of 10-20 years. Results showed that the pavement thicknesses were 400, 300, 500 and 560mm for GI, CBR, Asphalt Institute and AASHTO methods, respectively. The corresponding costs for development of the outcome structures are; ₦67,623,595.00; ₦61,701,412.00; ₦71,195,040.00 and ₦71,539,240.50 per kilometer of a standard two-lane carriageway. Thus, CBR method was recommended as the most economical while the Asphalt Institute and AASHTO methods the technically reliable and will provide most durable pavements. However, the Asphalt Institute and AASHTO methods of design are recommended for Nigerian flexible pavement construction, since they take into account the stress-strain properties of the soil and provide minimum maintenance cost.&picture=http://www.aascit.org/aascit/decorators/img/journal/920.jpg)
| [1] | Abubakar Baba Yahaya, Department of Civil Engineering, University of Ilorin, Ilorin, Nigeria. |
| [2] | Terseer Ako, Department of Civil Engineering, University of Ilorin, Ilorin, Nigeria. |
| [3] | Yinusa Alaro Jimoh, Department of Civil Engineering, University of Ilorin, Ilorin, Nigeria. |
The choice of an appropriate design method from Group Index (GI), California Bearing Ratio (CBR), American Association of State Highway Officials (AASHTO) and Asphalt Institute design methods has a great potential on the cost effectiveness in pavement development. The aim of the research is to compare different structural methods of flexible pavement analysis and design on the basis of cost and long lasting serviceable structure. Traffic volume count was carried out manually, while soil samples collected from selected locations were tested to determine the parameters to be used for the structural design using both empirical and mechanistic- empirical methods. Average GI of 4 was obtained for the subgrade. The soaked CBR of 13% was determined and used for the design of a pavement structure to support a total Equivalent Single Axle Load (ESAL) of 5.5x106 AADT traffic for a design period of 10-20 years. Results showed that the pavement thicknesses were 400, 300, 500 and 560mm for GI, CBR, Asphalt Institute and AASHTO methods, respectively. The corresponding costs for development of the outcome structures are; ₦67,623,595.00; ₦61,701,412.00; ₦71,195,040.00 and ₦71,539,240.50 per kilometer of a standard two-lane carriageway. Thus, CBR method was recommended as the most economical while the Asphalt Institute and AASHTO methods the technically reliable and will provide most durable pavements. However, the Asphalt Institute and AASHTO methods of design are recommended for Nigerian flexible pavement construction, since they take into account the stress-strain properties of the soil and provide minimum maintenance cost.
Keywords
Flexible Pavement, Design Methods, Costs, Group Index, California Bearing Ratio
Reference
| [01] | Claussen, A. I. M.; Edwards, J. M.; Sommer, P. and Ugé, P. (1977). “Asphalt pavement design – the Shell method”, Proc. 4th Int. Conference on the Structural Design of Asphalt Pavements. |
| [02] | AASHTO (1993). American Association of State Highway and Transportation Officials, AASHTO. “Guide for Design of Pavement structures”, Washington, D. C. |
| [03] | Burmister, D. M (1945), “The General Theory of Stresses and Displacement in Layered Systems”, J. Appl. Phys. 15: 89-94, 126-127, 296-302. |
| [04] | Oyedepo, O. J and Fanilola O. D. (2012), “Comparative analysis of Structural Methods of flexible pavement design”, Centre for Research and Development (CERAD). Journal of sustainable Technology vol. 3, No. 2 (November 2012), ISSN: 2251-0680. |
| [05] | Mathew, T. V and Rao, K. V. K, (2007), “Introduction to Transportation Engineering”, March 22, www.nptel.ac.in/..../lee-1-pdf. |
| [06] | Witczak, M. W. (2004), ‘’Assessment of the Allowable threshold Ruth depths by layers in asphalt pavement system’’, Transportation Research Board, NCHRP 9-19, National Cooperative Highway Research Program, Washington, D. C. |
| [07] | Embacher, R A and Snyder, M. B. (2001), “Life-Cycle Cost Comparison of Asphalt and Concrete Pavements on Low-Volume Roads”: Case Study Comparisons, Transportation Research Board, Paper No. 1749. |
| [08] | Uhlmeyer, J. S, Willoughby, K. Pierce, L. M. and Mahoney, J. P. (2000), “Top-Down Cracking in Washington State Asphalt Concrete Wearing Courses”, Transportation Research Record 1730, Transportation Research Board, National Research Council, Washington, D. C. |
| [09] | Gunalaan V. and Hidayu M. A. (2014), “Study on Comparative Flexible Pavement Thickness Analysis Using Various Design Method”, IJRET: International Journal of Research in Engineering and Technology. |
| [10] | Bindra, S. P. (2006), “A course in Highway Engineering”, 4th Edition, DhanpatRai publications, 427 pages. |
| [11] | Federal Ministry of Works and Housing, Lagos, Nigeria (1973), “General Specifications for Roads and Bridges”, Volumes 1 and 2. |
| [12] | Emesiobi, F. C. (2004), “Comparative Analysis of Flexible Pavement Design Method Using CBR Procedures In Evaluating Critical Fatigue And Rutting Strains”, Journal Of Agricultural And Environmental Engineering Technology, vol. 1 No 2 pp. 232-242. www.theijes.com. |
| [13] | Ekwulo, E. O and Erne, D. B. (2009), ‘Fatigue and Rutting strain Analysis of Asphalt Pavements Designed using CBR methods”, African Journal of Environmental science and Technology vol. 3 Number 12, pp. 412-421. http:/ www.academicjournals.org/AJEST. |
| [14] | Brown, S. F. (1997), “Achievement and Challenges in Asphalt Pavement Engineering”, International Society for Asphalt Pavement Lecture series in Seattle, Available at: http:/www.asphalt.org. |
| [15] | BS 1377 (1990), “Methods of Test for Soil for Civil Engineering”, British Standard Institution, London. |
| [16] | Federal Ministry of Works and Housing (FMWH), (1997), “General Specification (Roads and Bridges)”, Revised Edition (Volume II), Nigeria, Abuja: Federal Ministry of Works. |
| [17] | Ola, S. A. (1978), “Geotechnical Properties and Behavior of some Stabilized Nigerian Lateritic Soils”, Q. J. Engineering Geology, 145–160. |
| [18] | AASHTO. (1986), “Standard Specification for Transportation Materials and Methods of Sampling and Testing”, 14th Edition, American Association of State Highway and Transportation Officials: Washington. |
| [19] | Highway Capacity Manual (HCM), (2010), “Transportation Research Board, National Research Council, Washington D. C. |
| [20] | Rufi, U., Muhammad, I. K., and Afred, U. K, (2012), “Software Development (PAKPAVE) for Flexible Pavement Design”, International Journal of Multidisciplinary Sciences and Engineering, vol. 3, No. 11, November 2012. |
| [21] | Highway Manual – part 1, Design (2013). “Federal Ministry of Works and Housing”, Lagos, Nigeria. |
| [22] | Asphalt Institute (1999). Thickness Design, Lexington, Kentucky: The Asphalt Institute. |
| [23] | Kwara State Ministry of Works and transport, (2016), “Department of civil Engineering”, Ilorin, Kwara State, Nigeria. |
