Peaty soils are highly organic soils with high moisture contents, low shear strengths and high compressibility. It was shown through years of experience that construction on such soils will yield unexpected failures. Several researchers have undertaken studies to investigate the reinforcement effects of various geosynthetics. Peat however was less investigated especially with regards to geogrid reinforcement. Since peat covers an appreciable area in Malaysia and several other countries, this study is an attempt to evaluate the applicability of using Giroud and Han’s model for the design of unpaved roads on Malaysian peaty soils. It was found that as the tire inflation pressure increased and as the subgrade shear strength decreased, more aggregate thickness was required to offset settlements. It was shown that, although this model was applicable to these soils, a separate theoretical model addressing the particular qualities of peaty soils, should be attempted. Geotechnical engineers working in this field are advised to analyze and document tire inflation pressures and subgrade strengths as a prerequisite to constructing reinforced unpaved roads. Also it is advisable to investigate the effect cyclic loading has on reinforced peaty soils.

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A. A. Mahmood and L. L. E. Chung, “Experimental modelling of a reinforcement theoretical model on peaty soils,” International Journal of Applied and Physical Sciences, vol. 3, no. 3, pp. 75-84, 2017.