LAUSR

ABSTRACT In recent years, the study of piled foundations has gained increasingly more attention within the geotechnical community. There are different methods in the literature for calculating this foundation system, from the simplest to the most complex ones. This work aims to analyse the behaviour of piled foundations in different spacings using analytical and hybrid methods by means of the finite element method FEM-2D, considering the contribution of the surface element of foundation with the soil. For this purpose, we used square piled rafts composed of four piles of 0.30-m diameter, 5-m length, and variable spacing between piles (s/d = 4, 6 and 8). The geotechnical parameters were adopted from the calibration, validation and convergence tests grounded on a hybrid model in FEM-2D based on experimental and numerical results. It must be emphasized that this method produced reliable results for the resolution of piled rafts compared to the experimental and FEM-3D analyses. The conclusion is that theoretical analytical methods can provide a fast way to estimate settlements, particularly in the elastic section of the load settlement curve. The hybrid method based on the Equivalent pier and analysed in FEM-2D axisymmetric proved to be an important tool in predicting the behaviour of piled foundations, as it presents a gain in processing time when compared with FEM-3D analyses.