Estudo paramétrico da resistência ao cisalhamento de um solo de baixa capacidade de suporte.

Abstract

Soil mass movements in hills, slopes and slopes have intensified in recent decades. The Northeast Region is the leader in Brazil of the highest number of homeless people affected by instability problems, since the rupture of a massif causes material damages and social and economic losses. To mitigate the effects of slope instability are applied consolidation techniques, improvement and reinforcement in order to generate a global redistribution of stresses and deformations. Among these may be mentioned the techniques as chemical stabilization and containment with geosynthetics. The objective of this research was to perform a parametric study of the shear strength of a soil with low support capacity, in its natural state and after the use of chemical stabilization technique and the insertion of reinforcement materials (non-woven geotextile and geogrid). The research was divided in three stages to reach the proposed ends: soil characterization, soil chemical stabilization and evaluation of soil mechanical behavior. In the first stage, physical, chemical and mineralogical characterization of the soil were performed. In the second phase, simple compression tests were carried out with the purpose of determining an optimum content for soil chemical stabilization. Subsequently, samples of natural soil, stabilized soil and reinforced soils were submitted to non-densified and non-drained triaxial (UU) compression tests in order to analyze the geotechnical parameters of each model and the strength and stiffness gains of the improved soils in compared to natural soil. In general, the results indicated that the insertions of the non-woven geotextile and the geogrid contribute to the increase in shear strength. The soil chemical stabilization technique, compared to the geosynthetic reinforcement techniques provided better resistant behavior, since the cement insertion in the soil promoted superior results of shear strength of the studied soil. However, the present research did not consider the technical, economic and environmental advantages of each technology, since these aspects can make feasible the constructions with improved soil.