Performance Evaluation of Rigid Inclusion Foundations in the Reduction of Settlements

Abstract

In this study, numerical modeling is used to evaluate the performance of rigid inclusion foundations for settlement control considering the characteristic soils of the city of Brasilia, Federal District, Brazil. Two- and three-dimensional (2D and 3D) PLAXIS software models were used considering the Hardening Soil constitutive model parameters previously obtained, calibrated and validated by the authors. First, the general concepts regarding systems with rigid inclusions are presented. Then, parametric 2D axisymmetric numerical modeling is shown, where the spacing between inclusions, the height of the distribution layer and the soil conditions were varied. The load transfer mechanisms were analyzed, including the performance of rigid inclusions for settlement control. Finally, 3D modeling was performed with the information from a real project located in the Federal District. In the 3D modeling, the performance of the rigid inclusion foundation was compared with that of a slab foundation solution; then, the obtained settlements and angular distortions were compared with the serviceability limit states indicated in the literature. The results show that for the analyzed conditions, rigid inclusion foundations can be considered to be reliable foundation solutions. However, feedback from instrumentation cases in the city of Brasilia is required to further validate the design considerations.