Melhoramento de fundação de aterro com colunas de Jet-grouting estudo de caso: Baixa do rio Púnguè na cidade da Beira

Abstract

The construction of infrastructure can be constrained by the local soil conditions, as these soils play a very important role for the integrity of the foundations. Nowadays, it is common to build works along the coast which soils are characterized by low shear strength, associated with low permeability and high compressibility of these soils. For the construction of infrastructure in soft soils, an intervention is necessary to improve the properties of these soils because, otherwise, the build-up infrastructure may experience several pathologies that may contribute to their total or partial collapse. Currently, several techniques are available for the improvement of soft soil properties. Thus, this present work studies the Jet-grouting technique as reinforcement of foundation of an embankment to be built on soft soils, located in the lower part of the Pungwe River. This study consisted of designing the Jet-grouting columns based on empirical formulations and simulating their behavior in Plaxis 2D V.8.6, which is a software based on the finite element method. This study presents two methodologies for design Jet-grouting columns, however, it should be noted that because it is a relatively recent technique there is no unanimity regarding the design of this technique. After the designing of Jet-grouting columns, a comparison was made between the Jetgrouting columns and concrete piles with regard to the performance of the two solutions for the stated purpose. This comparison showed that the two alternatives are compatible with the case study. The quality control plays a very important role in the successful implementation of this technique, so during and after the implementation phases of Jet-grouting columns they should undergo strict quality control.