THE INFLUENCE OF VARIOUS VALUES OF SOILS SHEAR STRENGTH PARAMETERS OBTAINED BY DIRECT SHEAR TEST ON THE SIZE OF SPREAD FOUNDATION

Authors present some factors influencing the values of sandy soils shear strength parameters, obtained by direct shear test (DST) in another paper for the conference. In mentioned paper, the influences of density, shear area changing and number of specimens on the test result of clayey sand (SC) and sand with some fines (S-F) are analysed. In this paper, authors present how various values of soils shear strength parameters obtained by DST will influence the size of spread foundation placed in those soils. In the paper, the foundation model used by (Trevor L.L. Orr, 2008) is used. It is square pad foundation for a building, 0.8m embedment depth; groundwater level at base of foundation. The load is central and vertical (the permanent vertical load is 900 kN plus weight of foundation and variable vertical load is 600 kN). The size of foundation is designed by the new Slovak Technical Standard STN 73 1001 (valid from 01.04.2010, respecting the design approach number 2 of Eurocode 7 "Geotechnical design", Part 1: General rules" but with some differences), exactly by the design approach number 2 of Eurocode 7 "Geotechnical design", Part 1: General rules" and finally by the old Slovak Technical Standard STN 73 1001 (valid until 01.04.2010).