Evaluation of Techniques for the Improvement of Subgrade Soils in Flood and Rainfall Inundation Affected Areas
Improvement of Subgrade Soils in Flood and Rainfall Inundation Affected Areas
Keywords:
Subgrade soils, stabilization, cement, bitumen, polythene, polyesterAbstract
Highways are amongst the most costly resources contributing directly to the growth of any country’s economy. Subgrade soils as component of highways deteriorate normally from numerous factors resulting into flushing or excessive settlements of embankment involving huge maintenance costs. In this research, an attempt has been made to evaluate suitable technique for stabilization of commonly available subgrade soils of Pakistan based on cost effectiveness and ease in construction. The soils identified as A-3(0) by American Association of State Highway and Transportation Officials (AASHTO) criteria has been stabilized with conventional additives i.e. cement and bitumen in this research. The optimum content of each additive for stabilization based on their relative effectiveness was used. Trials were also made to economize the cost of stabilization from both conventional additives by controlled replacing of them with waste polythene and polyester fibers. The construction methodology for stabilization using waste fibers was also proposed. Cement was observed to be the most effective stabilizer with respect to strength and durability for A-3(0) soils. Bitumen was found effective but uneconomical for A-3(0) soils. Waste polythene and polyester wastes (organic materials) have potential to economize the cost of stabilization with cement and bitumen for A-3(0) soils. However, long term degradation of these organic materials in soil stabilized mixtures needs further exploration.
References
ASCE. Technical Engineering and Design Guides as Adapted from US Army Core of Engineers, No. 30 - Soil Sampling. American Society of Civil Engineers, Virginia, USA (2000).
American Concrete Institute. State-of-the-Art Report on Soil Cement. ACI 230.1R-90, ACI Materials Journal 87(4): 78-86 (1990).
Little, D., & S. Nair. Background for Development of Standard Practice for Modification and Stabilization of Subgrade Soils and Base Courses. National Cooperative Highway Research Program,Washington, USA, 20(07) (2008).
Portland Cement Association. Soil-Cement Laboratory Handbook. Portland Cement Association, Illinois, USA (1992).
Terrel, R.L., J.A. Epps, E.J. Barenberg, J.K. Mitchell, & M.R. Thompson. Soil Stabilization in Pavement Structures - A User Manual. FHWA Research Report. FHWA-IP-80-2, WA (1979).
Texas Department of Transportation. Guidelines for Modification and Stabilization of Soils and Base for Use in Pavement Structures. Texas Department of Transportation, Austin, USA, ftp://ftp.dot.state.tx.us/pub/txdotinfo/cmd/tech/stabilizati (2008).
United Facilities Criteria (3-250-11). Soil Stabilization for Pavements, TM 5-822- 14/AFJMAN 32/1019. Washington, USA (2004).
ASTM D-1883. Standard test practice for California Bearing Ratio of Soil. American Society for Testing of Materials, West Conshohocken, Pennsylvania, USA (2005).
ASTM D-2166. Standard Test Method for Unconfined Compression Strength of Cohesive Soils. American Society for Testing of Materials, West Conshohocken, Pennsylvania, USA (2006).
AASHTO M-85. Standard Specifications for Portland Cement. American Association of State Highway and Transportation Officials, USA (2010).
Townsend F.C. & J.B. Anderson. A Compendium of Ground Modification Techniques Report. Florida Department of Transportation, USA (2004).
Hicks, G.R. Alaska Soil Stabilization Design Guide. Federal Highway Agency, Alaska DOT Fairbanks, USA (2002).
US Army Technical Manual 5-822-14. Soil Stabilization for Pavements. Department of the Army, the Navy and the Airforce, USA (1994).
Hsuan Y.G., R.M. Koerner & A.E.J Lord. A Review of the Degradation of Geosynthetic Reinforcing and Various Polymer Stabilizing Methods. ASTM STP 1190, S.C. Jonathan Chang Edition, p. 228-243 (1993).
ASTM D-422. Standard Test Practice for Grain Size Analysis of Soil. American Society for Testing of Materials, West Conshohocken, Pennsylvania, USA (1998).
ASTM D-4318. Standard Test Practice to Determine Atterberg Limits of Soils. American Society for Testing of Materials, West Conshohocken, Pennsylvania, USA (2005).
ASTM D-854. Standard Test Practice to Determine Specific Gravity of Soil. American Society for Testing of Materials, West Conshohocken, Pennsylvania, USA (2000).
ASTM D-3080. Standard Test Practice for Shear Strength of Soil by Direct Shear Test. American Society for Testing of Materials, West Conshohocken, Pennsylvania, USA (1998).
ASTM D-698. Standard Test Practice for Moisture Unit Weight Relation of Soil. American Society for Testing of Materials, West Conshohocken, Pennsylvania, USA (2000).
National Cooperative Highway Research (NCHRP). Guidelines for mechanistic empirical design of new and rehabilitation pavement structure program. Transportation Research Board, National Research Council (2006).
ASTM D-2487. Standard practice for classification of soils for engineering purposes. American Society for Testing of Materials, Pennsylvania, United States of America (2011).
AASHTO M-145. Standard specifications for classification of soil and soil aggregate mixtures. American Association of State Highway and Transportation Officials. United States of America (2008).
Bowles, J.E. Foundation analysis and design. 5th ed. McGraw Hill Book Company, New York, United States of America (1996).
Engineering Road Note No. 5. Interim guide for prediction of pavement moisture for strength assessment of granular base course and subbase materials. Government of Western Australia (2005).
Alam M.J.B. & M. Zakariya. Design and construction of roads in flood affected areas, Journal of Engineering Concerns of flood, 12(3),91-99 (2006).
Ingles, O.O. & J.B. Metcalf. Soil stabilization: Principles and practice, Wiley, New York, (1973).
Nugroho S.A., A. Hendri & S.R. Ningsih. Correlations between index properties and California bearing ratio test of Pekanbaru soils with and without soaked. Canadian Journal on Environmental, Construction and Civil Engineering. (3)1:7-17 (2012).
ASTM D-88. Standard test practice for Saybolt Viscocity. American Society for Testing of Materials, Pennsylvania, United States of America (2007).
Maher, M. & D. Gray. Static response of sands reinforced with randomly distributed fibers. ASCEJournal of Geotechnical Engineering, 116(11):1015-1024 (1990)
Yetimoglu, T. & O. Salbas. A study on shear strength of sands reinforced with randomly distributed discrete fibers. ASCE - Journal of Geotextiles and Geomembranes 21(2): 103-110, (2003).
