GEOTECHNICAL MODELLING OF MECHANICALLY STABILIZED EARTH WALLS BUILT ON SOFT SOILS TREATED WITH GROUTING TECHNIQUES: CASE STUDY
Guido Paulo Simm Júnior1; Marcos Noronha2; Adroaldo Borges Júnior3
1 National Transport Infrastructure Department (DNIT); 2 Federal University of Santa Catarina (UFSC); 3 M.Sc. Student at Federal University of Santa Catarina (UFSC)
doi:10.20906/CPS/CILAMCE2017-1080
Resumo
The implementation of interchanges generally requires the execution of mechanically stabilized earth walls (MSEW) in locations of restricted Right-of-Way. A particularly complex situation arises when these structures are built on low strength, compressible soft soils. In these cases, it is necessary to treat the soft soil in order to obtain the geotechnical properties required to prevent excessive settlement or global failure of the structure. The aim of this paper is to evaluate the geotechnical behaviour of a MSEW to be built on soft soil previously treated with a grouting technique known as CPR Grouting. The CPR Grouting is a portuguese acronym for "Consolidação Profunda Radial", meaning deep radial consolidation. The injection of a grout mix induces soil consolidation and increases its resistance. The gain of stiffness is a characteristic of the final soil composite. The interchange with the MSEW is part of the implementation of a four lane highway (BR-470) being built in the State of Santa Catarina, Brasil. In the numerical analysis, we simulate the MSEW constructive process and analyse the strains and stresses acting upon the structure. The Shear Strength Reduction Technique (SSR), is employed to evaluate the interchange´s global safety factor. The theoretical results shows that the proposed soil treatment is efficient in improving the structure´s overall behaviour.
Palavras-chave: composite soil; soft soils; soil grouting