The Numerical Simulation About the “Overlapping Effect of Influence Zone” of the Construction Process of Multi-Stage Slope

The construction processes of a multi-stage slope supported by an united retaining structure of anchor-frame and anti-sliding pile were systematically studied on FLAC3D software, the influence zones of slope were drawn on CAD software. To explore the influence to the axial force of the anchor cables of the retaining structures that have been completed caused by the construction of the retaining structure by analyzing the relation between the prestress of the anchor cables and the influence zones of the multi-stage slope. The study shows that the influence zone caused by the construction will cross the influence zone of the next higher level slope if it is big enough and they will form a overlapping zone, the prestress of the anchor cable in this overlapping zone will change correspondingly, that is the "overlapping effect of influence zone" of the construction process of multi-stage slope; the area of the overlapping zone is related to the prestress applied initially, and the change of the axial force of the cables is related to the areas of the overlapping zone. This article summarizes the relationship between them, and presents the empirical formulas and provides a new method for designers in determining the ultimate prestress of the anchor cable after all the construction processes of a multi-stage slope.