An Investigation of the Influences of Particle Size, Size Gradation & Particle Shape on the Shear Strength & Packing Behavior of Beach Sands In saudi Arabia

Abstract

This investigation is a study of the shear strength and packing behavior of Dammam and Abhur Beach Sands in Saudi Arabia in terms of the geometric particle characteristics of size and shape. A large number of uniform size sands and a limited number of improved gradations are studied. Particle size is defined by mechanical sieving and particle shape is quantified in terms of sphericity and roundness. Surface texture is recognized to be a significant variable as is particle mineralogy. Packing behavior is studied with respect to the maximum and minimum limiting void ratios and void ratio spreads. Shear resistance is investigated in terms of the angle of internal friction. Results indicate that both packing behavior and shear behavior are influenced significantly by particle roundness and surface texture. The uniform sands tested were normalized into a linear strength-packing- shape relationship at a given relative density. Chal).ges in grading affect packing behavior more than strength behavior and the normalizations are rather sensitive to changes in void ratio spread. Normalizations appear significant in that they include surface texture variations and afford a possible technique for a more comprehensive approach to sand behavioral formulation in terms of the variables of particle size, size gradation, shape, surface texture, mineralogy and relative density_