Deformation characteristics of natural river sand under compression loading incorporating extreme particle diameters impacts

Abstract

The particle size is one of the most important factors influencing the behavior of soils. To study the impact of extreme particle diameters (Dmax and Dmin) and mean grain diameter (D50), a series of undrained triaxial compression tests were carried out with eighteen loose natural river sandy samples; considering a maximum particle diameter range (1.60 mm ≤ Dmax ≤ 4.00 mm), mean particle size ranges (0.25 mm ≤ D50 ≤ 1.00 mm) and the same minimum diameter Dmin = 0.0016 mm for the group1. For the group 2 consists of sandy samples having maximum diameter Dmax = 4.00 mm, minimum particle diameter ranges (0.0016 mm ≤ Dmin ≤ 0.63 mm), and mean diameter range (1.00 mm ≤ D50 ≤ 2.50 mm). The sandy samples were prepared with initial relative density Dr = 25% and subjected under a constant confining pressure (P’c = 50 kPa). The obtained test results indicate that the extreme particle diameters have significant effects on mechanical response of sandy soils and appear as important parameters for the prediction of the undrained shear strength of the tested soils. The maximum shear resistance can be correlated to the maximum relative diameter (Dmax/D50) and minimum relative diameter (Dmin/D50) of the tested samples.