


Threshold silt content dependency on particle morphology (shape and size) of granular materials: review with new evidence
Abstract
The threshold silt content is well known as a key parameter affecting the mechanical response of binary granular assemblies considering particle characteristics (size and shape).
In this context, the threshold silt content (TSC) is determined from different laboratory tests based on packing density response (emax and emin versus silt content “Sc”) and
theoretical approaches proposed by several researchers in the specialized published literature using the characteristics of host sand and
silt [emax(sand), emin (sand), emax(silt), emin (silt), Gs, Gf and x]. The analysis of the recorded data indicates that the
TSC derived from the (emax) curve appears more reliable than that obtained from the (emin) one. Moreover, it is found that the proposed analytical methods are suitable
to quantify the threshold silt content (TSC) than that determined experimentally using the packing density (emax and emin). In addition, the test results show that the
new introduced ratios [(D50s×As)/(D50f×Af)] and [(Cus×As)/(Cuf×Af)] determined based on particle
characteristics (shape and size) appear as appropriate parameters for predicting the threshold silt content (TSC) of sand-silt mixture of the compiled data from the published literature
as well as that of the present research related to Chlef sand, Fontainebleau sand and Hostun sand mixed with Chlef silt.
Keywords
threshold silt content, silty sand, particle shape and size, packing density