Modeling Resilient Modulus of Unsaturated Subgrade Soils under Concurrent Changes in Water Content and Temperature
Publication: Geo-Congress 2022
ABSTRACT
Seasonal variations and climatic events cause fluctuations of water content and temperature in shallow unsaturated soils. Such fluctuations can alter the resilient modulus (MR) of subgrade, which is an important parameter in the design and evaluation of pavements. This paper presents a new model to determine MR of unsaturated subgrade soils under concurrent changes in water content and temperature. The proposed analytical model offers the following two new features distinguishing it from alternative models: (1) the model separately accounts for two different soil water retention mechanisms, namely capillary and adsorption, which enables it to predict MR over a wide range of suctions, and (2) it explicitly incorporates the effect of temperature in the calculation of MR through employing temperature-dependent expressions for matric suction and the soil water retention curve (SWRC). The proposed model showed high accuracy when validated against experimentally measured MR values for several different soils reported in the literature. The presented model is simple and can readily be employed in practice to determine MR of subgrade soils under concurrent variations of water content and temperature.
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Geo-Congress 2022
Pages: 374 - 384
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Published online: Mar 17, 2022
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