Geoengineering Assessment of Subgrade Highway Structural Material along Ijebu Owo – Ipele Pavement, Southwestern Nigeria

FALOWO OLUSOLA OLUMUYIWA

Abstract


Geochemical, geotechnical, and geophysical investigations were carried out along Migmatite gneiss underlain Iyere – Ipele pavement (under construction) in order to assess the suitability of the imported subgrade soil. Also static water level (SWL) was obtained from five open wells along the highway. The geotechnical tests include specific gravity, grain size analysis, consistency limits, consolidation, compaction, and California Bearing Ratio (CBR), and shear strength; while geochemical tests were analyzed using X-ray fluorescence and Atomic Absorption Spectrophotometer (AAS). The results show that SiO2, Al2O3 and Fe2O3 constitute an average of 46.2%, 23.30% and 26.54% respectively of the soils chemical composition. The silica- sesquioxide ratio of the samples ranges from 0.89 to 0.96 and classified as true laterite. The topsoil along the highway is made of moderately competent/competent soil with resistivity ranging from 298 – 924 ohm-m and thickness of 3.1 - 8.2 m. The SWL varies from 3.3 - 5.5 m with an average of 4.3 m (moderately low). The soils are characterized by high California Bearing Ratio values, moderate shear strength (150 – 200kpa), and unconfined compressive strength (300 – 420kpa) with predominant kaolinite clay mineralogy group. The AASHTO and USCS classification system rate the soils as good and fair/good respectively

Keywords


AASHTO; silica-sesquioxide, geochemical; geoelectric section; highway; shear strength

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References


R.S. Millard, “Road building in the tropics. State of the Art Review,” 1990.

D. Croney, and J.N. Bulman, “The influence of climatic factors on the structural design of flexible pavements,” 3rd Int. Conf. on Structural Design of Asphalt Pavements, London. 67-71, 1975.

O.J. Nnanna, F.O. Odoko, and S.O. Alade, “Highway Maintenance in Nigeria, Lessons from other countries,” Research Department Occasional Paper Series, Central Bank of Nigeria, 2003.

W. Black, and N.W. Lister, “The strength of fill sub-grades, its prediction and relation to road performance,” ICE Conf. on Clay Fills, pp. 37-48,1978.

L.O. Momoh, O.J. Akintorinwa, and M.O. Olorunfemi, “Geophysical Investigation of Highway Failure - A Case Study from the Basement Complex Terrain of Southwestern Nigeria,” Journal of Applied Sciences Research, 4(6): pp. 637-648, 2008.

British Standard Institution, “Methods of Test for Soils for Civil Engineering Properties (BS 1377),” British Standard Institution: London, UK. 143p, 1990.

ASTM, “Standard Test Methods for Classification of Soils for Engineering Purposes (D2487-85),” Annual Book of Standards, 1989.

A.J. Smith, and R.F. Montgomery, “Soils and land use in Central Western Nigeria,” The Government of Western Nigeria, Ibadan Publication, 1962.

Geological Survey of Nigeria, “Geological Map of Southwestern Nigeria,” Geological Survey Department, Ministry of Mines, Power and Steel, Nigeria, 1984.

J.K. Mitchell, “Fundamentals of Soil Behaviour,” John Wiley & Sons. 422pp, 1993.

P.R. Vaughan, “Mechanical & hydraulic properties of tropical lateritic & saprolitic soils, particularly as related to their structure & mineral components,” Proc. 1st Int. Conf. Geomech in Trop. Lateritic & Saprolitic Soils, Brasilia, 3, pp. 231-262, 1985.

F.J. Martin, H.C. Doyne, “Laterite and lateritic soils in Sierra Leone,” Journal of Agricultural Science, 17, pp. 530-547, 1927.

A.I. Idornigie, M.O. Olorunfemi, A.A. Omitogun, “Electrical resistivity determination of subsurface layers, subsoil competence and soil corrosivity at an engineering site location in Akungba-Akoko, Southwestern Nigeria,” Ife Journal of Science, 8(2): 159-177, 2006.

D.P. Krynine, and J.R. William, “Principles of Engineering Geology and Geotechnics,” McGraw – Hill: New York, 159, 537p, 1957.

L.D. Wesley, “Some basic engineering properties of halloysite and allophane clays in Java, Indonesia,” Geot. 23, pp. 471-494, 1973.

P.H. Wright, “Highway Engineering, Sixth Edition,” John Willey and Sons: New York, 1986.

Federal Ministry of Works and Housing, “Nigerian general specifications for roads and bridges,” Federal Highway Department, 2:145–284, 1997.

S.K. Garg, “Soil Mechanics and Foundation Engineering,” 7th ed. Khanna Publishers: New Delhi. India. 673- 683, 2009.

U.S. Army, “The Unified Soil Classification System (USCS),” 1960.

AASHTO, “Guide for design of pavement structures. American Association of State Highway and Transportation Officials,” Washington, DC, 1993.

T.W. Lambe, and R.V. Whitman, “Methods of Estimating Settlement and Soil Mechanics,” S. I Version, John Wiley & Son. Journal on Mechanics and Foundation Division American Society of Civil Engineering. Vol. 90, 42p., 1979.

C.O. Okogbue, “Evaluation of Strength Properties of Mineral Soil,” Nig. Journ. Min. and Geol., 22(1 & 2): 89 – 97, 1985.

R.A. Abeyeskera, C.W. Lovell, and L.E. Wood, “Stress Deformation and Strength Characteristics of a Compacted Shale Clay fills”. Institution of Civil Engineers: London, UK.1-14, 1978.

F.G. Bell, Engineering Geology, 2nd Edition. Elsevier: London, UK. 207 - 248, 2007.




DOI: http://dx.doi.org/10.36785/jaes.v10i1.374

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