Comparação numérica entre as técnicas de tratamento de solos moles: CPR Grouting, colunas granulares e drenos verticais

Abstract

Understanding the different treatment techniques for a soft soil layer is essential for a geotechnical engineer, manly in choosing the right solution that meets the design objectives required. Experimental comparisons or the use of analytical formulations can be onerous and complex. Thus, the present work presents a numerical comparison of the behavior of embankment on soft soils using the techniques of CPR Grouting, stone columns and vertical drains are used. The analysis was performed with the support of the Plaxis 2D software. The results show that the conversion to plane strain can be performed with the use draining walls or by equivalent homogeneous means, including the correction of permeability, geometry or stiffness when necessary. After confirming the equivalence between the results in the cells unitary, the techniques were compared for a embankment. In this study, it was observed that, for similar substitution reasons, CPR Grouting provides the smallest magnitude of settlement, taking safety factors in instability control to more satisfactory values. The time periods to stabilize the settlements and the advantages of suppression of temporary overload and reinforcement of geogrid are similar between CPR Grouting techniques and stone columns. However, the embankment technique in vertical drains presented time much upper settlement and stabilization, as well as the lower safety factors, even with the use of geogrids and overloads to accelerate the process of consolidation.