Geotechnical Centrifuge Modelling of Railway Embankments on Soft Clay Foundations

Abstract

Many embankments of the Dutch railroad network are over a hundred years old and were constructed on very soft clay and peat layers. The weight of the trains and the use of the railway infrastructure have increased over time. A recent assessment of the stability of existing infrastructure revealed that the railway embankment is demonstrably not in compliance with the required standards in several locations. However, although considerable deformations exist in some cases, most of these embankments have remained stable under current use. This may indicate that several aspects of the train loading characteristics in relation to the foundation soil strength are not fully understood in the context of railway embankment stability. To better understand the effect of train loading and increased use of railroads on the soil strength, a geocentrifuge test program was executed through the GEOLAB initiative. During this study a series of centrifuge tests were performed of a railroad system composed of a sandy embankment underlain by a soft clay foundation, aiming to provide a better understanding of the potential effects of train loading characteristics and the increased use of railroads on the foundation soil strength. The models were tested in a geotechnical centrifuge at a gravitational acceleration field of 20g and included reference static monotonic tests to failure and tests modelling different train loading conditions, including different loading frequencies and amplitudes. This paper presents the design of the experimental setup, a description of the behavior’s observed during the execution of the tests and preliminary results and observations of the project SURE performed as part of the transnational access initiative by GEOLAB. Further presentation and analysis of the results will be presented in a future companion article.