Laboratory model tests on natural sand from Skopje region

From the detailed experimental series of 1‐G laminar box experiments on Skopje sand it was clear that additional model tests were needed having similar initial conditions as the examined sand in the laminar box. Series of index experiments on a new shipment of sand are performed to determine mechanical properties and to prove the sample consistency. Also series of simple shear cyclic tests are made on loose specimens with a 20, 25, 30 and 35% relative densities and effective pressures of 50 and 100kPa. Moreover, series of simple shear liquefaction tests and series of triaxial undrained liquefaction tests with same initial condition of 30% relative density and 50kPa effective pressure are considered. Such initial conditions represent additional difficulties in the preparation of the models and their testing. The results obtained from these tests greatly enhance the knowledge of the sand response when different levels of dynamic loads are applied and the potential of liquefaction is considered carefully.