Evaluation of Rock Slope Stability on the Northeastern Limb of Makhul Anticline, Northern Iraq

Makhul anticline is about 58 km long in the northeast of Tikrit City, where six slope site stations within the Fatha Formation are selected for this investigation. Kinematic analysis and the slope mass classification system are used to search and analyze the potential level of stability by applying two packages (DIPS v6.008 and SMRTool v205). Based on the kinematic analysis using the DIPS v6.008 system, it is found that plane sliding occurs at stations (1, 2, 5, and 6), wedge sliding occurs at all stations, direct toppling occurs at stations (4 and 6), and oblique toppling occurs at station (6) that is considered the least frequent type of failure in the study area. As for estimating the mass of the slope according to the results of the separate SMR-Tool program and the continuous CSMR program, it is shown that the worst case of flat slide is at station (3), which is completely unstable and falls within the fifth category (V) with a failure rate of 0.9. The unstable stations are the plane sliding at station (6) and the wedge sliding at station (1), and both are within the fourth category (IV) with a failure rate of 0.6, whereas the partially stable stations are the plane sliding at station (1) and the wedge sliding at stations (2, 3, 4, 5, and 6), the direct toppling at stations (4 and 6), and the oblique toppling at station (6), which fall within the third category (III) with a failure rate of 0.4.