Effect of particle fabric on the coefficient of lateral earth pressure observed during one-dimensional compression of sand

The effect of initial particle fabric on the one-dimensional compression response of Fraser River sand was investigated. One-dimensional compression with lateral stress measurement was carried out on reconstituted Fraser River sand specimens using an instrumented oedometer. Laboratory specimens were reconstituted by air pluviation, tamping, and vibration and were prepared with an initial relative density ranging from medium loose to very dense. For Fraser River sand in one-dimensional compression, air-pluviated specimens yielded the highest values for the coefficient of lateral earth pressure at rest (K-o), tamped specimens produced the lowest K-o values, and vibrated specimens produced intermediate K-o values. The results from the present study demonstrate that specimens resulting from different laboratory reconstitution methods (i.e., different initial particle fabrics) exhibit different one-dimensional compression responses and produce different K-o values. A fabric factor was introduced to account for the effect of the initial particle fabric on the measured coefficient of lateral earth pressure at rest. Using the fabric factor, the constant volume friction angle, and the specimen relative density, a new empirical equation defining the coefficient of lateral earth pressure at rest during normally consolidated loading is proposed.