An insight into the prediction of limiting fines content for mixtures of sand with non-plastic fines based on monotonic and cyclic tests

The paper offers insight into the determination of threshold fines content, FC_th , or limiting fines content, based on experimental data from both undrained monotonic and cyclic tests performed on sand-silt mixtures obtained by mixing different amounts of non-plastic fines (in a range 0-40%) to a host silica sand. Different methods were adopted for the identification of FC_th such as: variation of index properties (maximum and minimum void ratios) with fines content, change of critical state parameters with fines content (monotonic loading), variation of the cyclic resistance ratio at a reference number of loading cycles with fines content (cyclic loading). The threshold fines content assessed by experimental data through monotonic and cyclic test results were then compared with the values inferred from several analytical relations to verify to what extent the predictions made by these equations could be reliable.