The aim of the paper is to provide some aspects regarding the behaviour of laterally loaded piles in loessial soils, by presenting and analysing the results of several in situ tests on large diameter bored piles in this type of soil. The major feature of loess is that it exhibits a massive decline of its strength and stiffness parameters when it comes into contact with water, leading to the collapse of its structure even under self-weight and creating difficult conditions for foundations. The load tests were performed both in natural moisture content loess and also in saturated loess. The results obtained by means of instrumentation are back-analysed using current analytical methods and also by finite element method using a numerical model in the geotechnical computation software Plaxis 3D.
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