Experimental data of laboratory testing of sands from plane strain compression tests are much less available than those from triaxial tests. In order to get the strength parameters of the sands used in 2D piled embankment model tests and the micro parameters used in the DEM simulations of these tests, a series of tests are done using plane strain test apparatus. These tests consist of three groups with different grain sizes: two coarse sands and a medium sand. For these tests, the relative density was set to 85%. A relative density of 50% was applied to assess the influence of the density. The sample size is large, 600mm^∗ 600mm^∗ 300mm (length^∗ width^∗height) in order to eliminate the side friction effects of the container. The results prove that relative density has a significant impact on the experimental results for the same type of sand, while the grain size has negligible impact. The high peak friction angles are attributed to the feldspar component, confining condition of plane strain tests, and high relative density. Tests of sands with different grain sizes and relative density also provide detailed data for the DEM numerical simulations. The high friction properties can be calibrated using the non-circular particle clumps.