Effect of Base Coarse Layer on Load-Settlement Characteristics of Sandy Subgrade Using Plate Load Test

Authors: A. Nazeri, R. Ziaie Moayed, H. Ghiasinejad

Abstract:

The present research has been performed to investigate the effect of base course application on load-settlement characteristics of sandy subgrade using plate load test. The main parameter investigated in this study was the subgrade reaction coefficient. The model tests were conducted in a 1.35 m long, 1 m wide, and 1 m deep steel test box of Imam Khomeini International University (IKIU Calibration Chamber). The base courses used in this research were in three different thicknesses of 15 cm, 20 cm, and 30 cm. The test results indicated that in the case of using base course over loose sandy subgrade, the values of subgrade reaction coefficient can be increased from 7  to 132 , 224 , and 396  in presence of 15 cm, 20 cm, and 30 cm base course, respectively.

Keywords: Base course, calibration chamber, plate load test, loose sand, subgrade reaction coefficient.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1317436

References:

[1] Kim, D. and Park, S., 2011, May. Relationship between the subgrade reaction modulus and the strain modulus obtained using a plate loading test. In 9th World Congress on Railway Research, Lille-France.
[2] Moayed, R. Z. and Bolandi, M. A., 2012. Determination of Subgrade Reaction Modulus of Two Layered Soil. In 3rd International Conference on New Developments in Soil Mechanics and Geotechnical Engineering (pp. 28-30).
[3] Edincliler, A. and Cagatay, A., 2013. Weak subgrade improvement with rubber fibre inclusions. Geosynthetics International, 20(1), pp.39-46.
[4] ASTM D3080, “Standard test methods for direct shear test of soils under consolidated drained conditions,” American Society for Testing and Materials, 2011.
[5] ASTM D1883, “Standard Test Method for California Bearing Ratio (CBR) of Laboratory-Compacted Soils,” American Society for Testing and Materials, 2016.
[6] ASTM D1241, “Standard Specification for Materials for Soil-Aggregate Subbase, Base, and Surface Courses,” American Society for Testing and Materials, 2015.
[7] ASTM D1557, “Standard Test Methods for Laboratory Compaction Characteristics of Soil Using Modified Effort (56,000 ft-lbf/ft3 (2,700 kN-m/m3)),” American Society for Testing and Materials, 2012.
[8] ASTM D1196, “Standard Test Method for Nonrepetitive Static Plate Load Tests of Soils and Flexible Pavement Components, for Use in Evaluation and Design of Airport and Highway Pavements,” American Society for Testing and Materials, 2012.
[9] Ziaie_Moayed, R, Khalili, A., Nazeri, A. (2017),” 3D Numerical Analysis of Plate Load Test Results on Calibration Chamber ", Proceedings of 19th Int. Conf. on Geomechanical Analysis and Geomechanical Tests, ICGAGT 2017, Istanbul, Turkey, July. 2017, P.2674-2679.
[10] Bowles, J. E. 1997. Foundation analysis and design, 5th edition, McGrawHill Inc., New York.
[11] ASTM D1556, “Standard Test Method for Density and Unit Weight of Soil in Place by Sand-Cone Method,” American Society for Testing and Materials, 2015.