Centrifuge modelling of sand and sawdust embankments on peat for sustainable infrastructure development

Abstract

Previously accepted methods to develop infrastructure across peatlands such as roads or railways typically excavated out the peat and substituted it with granular material. Such solutions, especially the alteration to drainage, can disturb peatlands and emit large amounts of greenhouses gases. The work on the GEOLAB / CLARIFIER (Centrifuge modeLling of peat embAnkments foR critical inFrastructure In EuRope) project explores the use of an innovative combination of sawdust and sand as embankments for rural roads, a technique which has previously been used in Norway. Although this previous work shed light on the deformation behaviour, very little is currently known about the performance during traffic loading and about the failure mechanisms of such embankments. A series of centrifuge tests were performed as plate loading tests and on sawdust and sand embankments at Deltares. The testing was carried out on intact peat using large block samples which were recovered from a site in Trondheim, Norway. In addition to extensive instrumentation, two colour cameras were used to capture images throughout the centrifuge tests to allow image-based deformation analysis. This paper provides an overview of the project as well as some preliminary results.