0000005569 00000 n Recently, the factor of safety of rock slopes against the wedge failure … (2016) A method for assessing discontinuity poles for potential wedge sliding. The rock type was a very competent, massive granite Block or wedge slides occur when a soil mass is shattered along joints, seams, fissures, and weak zones by forces emanating from adjacent soils. The present work focuses on the study of the wedge failure, which occurs as sliding of a mass of rock on two intersecting planes, generally discontinuity planes. From a rock slope design perspective, the most important characteristic of a discontinuity is its (a) Wedge failure on two Planar failure in rock in which a intersecting discontinuities with discontinuity 'daylights" the a line of intersection which slope face identify the relevant failure modes based on information of wedge geometry and forces acting on the wedge. 0 Overall stability is always checked for the possibility of deep-seated failure through the rock mass and the method of slices is usually the tool of choice. Although, field observations may provide valuable clues the about ); can analyse factor of safety sensitivity to changes in slope g eometry and material properties; more Introduction. 1. of wedge failure is evident. Natural events include failure due to flash flood, excessive seepage, pore pressure, seismic event, presence of weak discontinuities across the rock slope, shear zones, toe cutting of slope by meandering river leading to unstable slope due to change in slope geometry. Wedge Failure Wedge failure can occur in rock mass with two or more sets of discontinuities whose lines of intersection are approximately perpendicular to the strike of the slope and dip towards the plane of the slope. If sliding distance of rock block or rock mass that detached by sliding, toppling, or falling was 1(b)]. trailer Plane failure; Wedge failure. Thus, the stability assessment method has to be capable of coping with this uncertainty. There are several tools of increasing complexity that can be used to facilitate a limit equilibrium analysis of rock slopes. Circular failure generally is observed in slope of soil, mine dump, weak rock and highly jointed rock mass. The wedge failure phe-nomena in a rock slope. Toppling failure is one of the most common modes of failure of rock slopes in layered rock strata. (10 marks) (c) Calculate the factor of safety for wedge failure mode using the formula in Figure Q1(e) when the rock slope is in wet conditions (the student must demonstrate its calculation). Stability Analysis of Rock Slopes with Plane and Wedge Failure by Means of a Pocket Calculator Random sets arise as a powerful tool to deal with uncertainty, even when limited information of inputs is available. This type of failure occurs when there are fissures, joints, or weak soil layers in slope, or when a slope is made of two different materials. Slope stability in mining and civil engineering projects is always a problem of great concern. A wedge failure in a rock slope 21 m (70 ft) high was stabilized by unloading the top third of the failure, constructing a concrete wall to reinforce the toe, and installing tensioned rock anchors. In this code only one mode that is plane wedge failure ls described (see Fig. C. Wedge failure factor of safety analysis. 110 0 obj<>stream The only difference between the translational failure and the wedge failure is that translational failure only occurs in case of infinite slopes but wedge failure can occur in both infinite and finite slopes. and/or the equilibrium conditions of natural slopes. Flow slides can occur in dry and wet soils. Static and seismic slope stability analysis confirmed the global stability of the slope. of Colombia, Carrera 30 No. ROCK SLOPES MODELING Location of the stations along the Werka descent is traced by the GPS. In many cases, rock mass slope stability is controlled by discontinuities, which determine the most likely mechanism of failure, depending on joints and slope geometry. of Civil and Agricultural Engineering, National Univ. Slope stability in mining and civil engineering projects is always a problem of great concern. For rock slopes usually two free surfaces (lower outcrop and upper outcrop) are present, figure 2. Translational slides in rock masses are dependent upon the spatial arrangement of the discontinuities within the mass and their relationship to the geometry of the slope. The stability of the rock wedge is controlled by: joint sets dip and dip direction, slope geometry and direction, external forces (including water pressure and earthquake) and rock and joints mechanical properties. Note: The application Rock Slope can evaluate a broken rock wall by a shear failure (rock slides) using a planar and/or a polygonal shear plane and a rock wedge. Calculated factor of safety = 0.4. The key question with regard to rock slopes along highways is their long-term stability since failure of a rock slope can have serious consequences. Wedge failure The slope failure occurred along the plane of the soil mass is known as wedge failure. 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