Stabilization of deep seated movement in a Saprolitic Massif supporting a highway viaduct

摘要

The results of geological and geotechnical studies carried with relation to VA-19 viaduct of Immigrants Highway, one of Brazil's most important highways, crossing the "Serra do Mar" Mountain Range are presented. The soil and rock massif that sustain the foundations of this viaduct was undergoing a slow movement along a deep seated slide surface for more then a decade, affecting the structure in a stretch between three columns more than 80 meters high. After monitoring the movements both in the massif and in the structure, a stabilization project was elaborated. The paper presents the concept and the execution of the remedial works, based on WL lowering through a drainage tunnel excavated into the soil and rock massif, as well as the instrumentation results during the works and after their conclusion.