Comportamento de aterros sobre solos enrijecidos com CPR grouting

Abstract

The present study has the objective of analyze numerically the behavior of two instrumented experimental landfills (landfill test A and landfill test B), located in the area that composes the Palms Recreio Condominium Residential. The landfill test A was built on a layer of soft clay of 8.0 m thick, where drains were installed for acceleration of settlements. In the area of the landfill test B, in addition to the installation drains, the squeezing of compressible soil through the CPR Grouting technique was carried out, in order to significantly reduce the expected settlements. In each test landfills have been installed 3 plates for measuring the vertical displacement, 5 vertical magnetic spiders, 1 profilometer for monitoring the vertical displacements, 2 piezometers to control porepressure and 1 inclinometer for monitoring the horizontal displacements To reproduce the behavior of experimental landfills, the Plaxis program of finite elements was adopted. Initially, the calibration of the model was carried out, comparing the numerical predictions obtained for the landfill test A (without CPR Grouting) with the data provided by field instrumentation. Subsequently, the prediction of the behavior of the landfill test B (with CPR Grouting) was carried out, looking for representative deformability parameters of the stiffened soil. The main conclusions are the increase in soil rigidity after stiffening with the CPR Grouting technique, leading to significant reductions of the displacements. The deformability modulus (E) of the soil with CPR Grouting was 12 times higher than that of the soft soil without CPR Grouting. In addition, the stiffening leads to a homogenization of the compressible soil layer.