Determination of representative values from derived values for verification with limit states with EN 1997 : guidelines for the application of the 2nd generation of Eurocode 7 : geotechnical design

This document summarizes the global process of designing geotechnical structures, as given in the 2nd Generation EN 1997, and highlights the step where the designer must determine representative values for limit state verifications based on ground investigation data. This guideline explains the different concepts related to the ground property values, including measured, derived, representative, nominal, indicative, characteristic, design and best estimate values. The text describes procedures for determining representative values in special cases, which are common in practice. These situations include dealing with limited samples, with depth-dependent properties, and data from different sources. Five examples are presented and solved, covering various aspects such as different geotechnical structures and limit states, different number of derived values, different distribution function, and independent and depth- dependent ground properties. This guideline is an essential tool for designers to understand how to determine representative values for the design and verification of geotechnical structures, in accordance with the procedures outlined in the Second Generation of Eurocode 7.