Assessment of Rock Slope Stability along Bazian-Basara Main Road, Sulaimani, NE Iraq

Abstract

In Iraq, the majority of rock slope instability issues along highways result in road deterioration or collapse. Among these is located along Bazian-Basara main road on the southwestern limb of the Bazian anticline fold. For the study of this problem, stations along the road within Sinjar and Pila Spi formations are selected. The study included an investigation of the slopeʾs stability and the occurrence and potential failures. The stability of the slopes was evaluated using the SMRTool-v205 software, which is used to classify the condition and degree of the slopeʾs stability. The stability analysis results demonstrate the possibility of wedge sliding and direct toppling occurrence in the stations 4,8, and 10, thus, described as unstable slopes and need important intervention. Whereas the dominant failure modes in stations 3,4,6,7,9, and 10 and stations 1 and 5 in the slope with a dip of 90̊ are direct toppling, flexure toppling, and wedge sliding, therefore, described as normal and partially stable slopes and need to systematic monitoring. As well as, direct toppling is the dominant failure mode in stations 1 with a slope of dip 20̊ and stations 2,5, and 7 which are classified as good and stable slopes but need to be monitored occasionally.