Characterization of granular lateritic soils as pavement material

Due to the scarcity of crushed stone aggregates, the feasibility of using locally available granular materials and marginal aggregates as pavement material is being explored in most part of the world. Granular lateritic soil (locally known as Moorum) has been used as a sub-base material for road construction in India. The characteristics of lateritic soils vary considerably based on their mineralogical composition, microstructure of soil particles, climate, parent rock and degree of laterisation. Therefore a detailed characterization of granular lateritic soils available locally in India is very much essential for its use as pavement material. In recent years, there is a sway towards mechanistic design of pavements, which requires the mechanical properties of all the materials being used in the pavement layers. Material property in terms of elastic modulus or resilient modulus and Poisson’s ratio are two major input parameters for mechanistic design. Granular materials show stress hardening characteristics and behave non-linearly under repeated loads. Considering the requirement of characterization of granular lateritic soils in India, a comprehensive laboratory study was taken up. This paper presents the results of various tests conducted on these soils collected from the eastern part of the country and the correlations established between different parameters for easier determination of complex soil properties.