At present,the study of loose sand mainly focuses on some commonly used models which are based on the Hertz-Mindlin and Walton contact theories.In this paper,the authors tested the capability of various rock physics models to predict dry modulus of the sand samples by comparing the estimates with results measured in laboratory.The study shows that the traditional model of unconsolidated sand is not good at characterizing its elastic properties.Using either the HMR or HMS theories to define the high porosity endpoint gives a lower-prediction of the dry bulk modulus which will have a much bigger error when combined with HS lower bounding equation.Both HMR and WR result in an over-prediction of the dry shear modulus because they do not consider the deformation across the contact.As WS cannot give a good fit to all the areas,it is rarely used.Despite the fact that the results are somewhat lower than the real data,the dry modulus is best described by HMS.With the help of the HS higher bounding equation,the predicted dry modulus agrees fairly well with the measured data.So the new constructed method has better application effect and deserves much attention.