Stability analysis of double V-shaped gully embankment: dimension-reduced calculation method

Slope stability is generally analyzed by a two-dimensional (2D) method, ignoring the spatial effect (SE), which no longer meets the evaluation accuracy requirement. This problem is particularly prominent for embankments built on double V-shaped gullies (E-DVSG), which is a typical but unique topography in mountainous areas. Moreover, the technical requirements for engineers will increase sharply if a three-dimensional (3D) slope stability calculation method is adopted. To tackle this issue, pragmatically, a dimension-reduced slope stability analysis method (DR-SSAM) considering the SE of the E-DVSG was proposed and verified by a case study. Specifically, the DR-SSAM obtained the 3D safety factor of the E-DVSG by using the spatial effect curves and the safety factor from the 2D model. The results showed that this method was rational and efficient for engineering applications. In addition, the SE generation mechanism and condition, along with the influences resulting from the major factors, were addressed thoroughly. Key words: double V-shaped gully, embankment, slope stability, dimension-reduced, spatial effect, finite element method. La stabilite des pentes est generalement analysee par une methode en deux dimensions (2D), sans tenir compte de l'effet spatial (ES), qui ne repond plus a l'exigence de precision de l'evaluation. Ce probleme est particulierement important pour le remblai construit sur un ravin en forme de V double (R-RFVD), qui est une topographie typique mais unique en region montagneuse. En outre, les exigences techniques pour les ingenieurs augmenteront grandement si une methode de calcul de stabilite des pentes en trois dimensions (3D) est adoptee. Pour aborder cette question de facon pragmatique, une methode d'analyse de la stabilite des pentes a dimension reduite (MASP-DR) tenant compte de l'ES du R-RFVD a ete proposee et verifiee par une etude de cas. Plus precisement, la MASP-DR a obtenu le facteur de securite 3D du R-RFVD en utilisant les courbes d'ES et le facteur de securite du modele 2D. Les resultats ont montre que la methode etait rationnelle et efficace pour les applications d'ingenierie. En outre, le mecanisme et l'etat de la generation de l'ES ainsi que ses effets decoulant du facteur majeur ont ete examines attentivement. [Traduit par la Redaction] Mots-cles: ravin en forme de V double, remblai, stabilite de la pente, dimension reduite, effet spatial, methode par elements finis.
Introduction Highway construction in mountainous areas involves plenty of tunnel excavation, cutting, and digging, which always results in abundant earth and stone wastes. Therefore, high-filled embankments have been extensively implemented [...]