On creep laboratory tests in soil mechanics

Abstract

Soil exhibits creep behaviour, which is the development of timedependent shear and/or volumetric strains at a state of constant effective stress. Creep is controlled by the viscous like resistance of soil structure. Creep behaviour influences the long-term settlement of grounds and movement of slopes; therefore it is of significance in geotechnical engineering applications. Creep laboratory tests, mainly one-dimensional and triaxial creep tests, are used to investigate the creep characteristics of soils and to predict the creep behaviour of soil in the long term. Conventional creep tests involve loading a soil sample to a specific effective stress and then allowing the sample to creep under constant effective stress. However, in order to capture the long term creep behaviour of soil, long duration creep tests are required. Therefore, the creep tests are not only laborious and time-consuming which render them impractical in many applications, but also associated with some difficulties and inaccuracies that need to be dealt with. In this study, a review on the conventional laboratory creep tests, the main difficulties associated with them, and the solutions proposed to alleviate these difficulties (if there are any) are presented. The possible sources of inaccuracies in the test results are discussed and practical recommendations are proposed to minimise the inaccuracies in the results. © Springer-Verlag Berlin Heidelberg 2013.