Avaliação da eficiência da técnica de consolidação profunda radial CPR Grouting no tratamento de solos compressíveis

Abstract

The treatment technique Deep Radial Consolidation Grouting (CPR Grouting) is the grout pumping inside the soft soil layer under high pressure, interspersed with geodrains previously installed. The treatment results in the decrease of voids in the compressible layer and increase in resistance leading to a significant reduction in settlements. This thesis aims to compare the behavior of two experimental embankment, run on soft soil from the instrumentation data analysis. In a embankment, was adopted the Deep Radial Consolidation Grouting (CPR Grouting) technique for treatment of soft soil, the second embankment was just with geodrains. Embankments have been implemented in the construction area of the Condominium Palms Residential Recreation, located in Miguel Antonio Fernandes Avenue, Recreio dos Bandeirantes, Rio de Janeiro - RJ. In this region, the soft soil thicknesses are of the order of 8 m. The characterization of the soft soil was carried out from the results of field tests, SPT and pressuremeter, and one-dimensional consolidation tests in the laboratory. Geotechnical instrumentation consisted of settlement plates, magnetic spiders and perfilometers, for monitoring of settlements; inclinometers to monitor the horizontal displacements, and piezometers for control of pore pressures. From the consolidation tests, evaluating the quality of the samples was performed to ensure the representation of the parameters. The estimates of final settlements , completed on the design phase, were reevaluated based on the new parameters adopted. The results allowed to evaluate the effectiveness of deep radial consolidation technique. There was a significant reduction in settlements on the treated soil, as well as a decrease of the horizontal displacements. It emphasizes the technical efficiency, which also allows a significant acceleration of settlements with the installation of geodrains.