Estudo comparativo entre cortina atirantada e solo grampeado para contenção de taludes

Abstract

This study presents a comparative analysis of slope retention techniques using soil nailing and anchored wall systems, applied to homogeneous slopes with heights of 8, 12, and 16 meters. The study focused on geotechnical stability, structural performance, and construction costs, based on a sandy-silty soil (γ = 18 kN/m³, c = 10 kPa, ϕ = 31°). The Slide 6.0® software, developed by Rocscience, was used, employing the Fellenius limit equilibrium method. Design procedures followed the Brazilian standards ABNT NBR 5629:2018, ABNT NBR 11682:2009, and ABNT NBR 16920-2:2021. Results showed that for 8-meter slopes, soil nailing was 16.6% more cost-effective, while for 12-meter slopes, the costs of both techniques were nearly equivalent. For 16-meter slopes, the anchored wall proved more economically advantageous, with a cost reduction of 2.62%. The construction differences between the two systems stem from the fact that anchored walls require strict execution control, mainly due to the prestressing of anchors, whereas soil nailing involves lower initial costs but is more sensitive to deformations. It is concluded that the choice of retention system should consider slope height, project costs, and site-specific conditions, with soil nailing being more suitable for lower slopes and anchored walls preferable for deep excavations.