Numerical Analysis 3D of a Deep Circular Excavation in the City of Rio de Janeiro

摘要

At present, due to the need for engineering works of large scale, we have the challenge of solving problems related to deep excavations, where instability problems often occur. In this paper is presented the analysis and validation of the excavation of the service well PS - 39, of the executive project of collectors for treatment of sanitary sewage, located in the city of Rio de Janeiro. This well was constructed using a contention system of a wall of secant column, ring structure type of "shotcrete" covering the columns, and a slab of "jet grouting" anchored with passive tiebacks. The soil parameters of the different layers that compose the geotechnical profile, necessary for numerical modeling, were determined based on the geotechnical information available of the field instrumentation, laboratory data and specific literature review, considering the Mohr-Coulomb constitutive model. The results and interpretation, of the stresses and displacements during the excavation process, were determined using the PLAXIS 3D (2012) program. These results were validated with the measurements determined by instrumentation; then the numerical model will predict rationally the behavior of the set soil-structure during the excavation process. This allows to solve similar problems in advance, allowing proper planning.