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Project Dataset <br /> ' The dataset used to perform this evaluation was collected by GEI during annual monitoring of the <br /> South Quarry highwalls between 2014 and 2019. The annual monitoring program is performed <br /> within the actively mined areas of the South Quarry and is intended to monitor changes in the <br /> ' bedrock as the highwall retreats during mining. The recorded data includes orientations of joints, <br /> fractures, foliations, and shear zones that could impact the strength or stability of the rockmass. <br /> The information is collected annually along exposed highwalls that were mined since the previous <br /> ' inspection. The raw data includes 901 discontinuity measurements which were used in the <br /> kinematic analysis without processing or filtering. Each discontinuity type was equally weighted <br /> for this analysis. <br /> ' The friction angle used for the kinematic evaluation was obtained from previous studies using <br /> direct shear test performed on samples obtained from the South Quarry. The tests were performed <br /> as part of a stability evaluation and included testing foliations, open fractures, and saw cut joints. <br /> ' A total of 23 direct shear tests were performed and the average friction angle is 25 degrees. A <br /> value of 20 degrees was selected for this evaluation. <br /> ' Kinematic Evaluation <br /> The kinematic evaluation was performed to evaluate several joint-controlled failure types, <br /> including planar (block) sliding, wedge sliding, flexural toppling, and direct toppling. The <br /> ' analyses were performed using the computer programs Dips (V8.0), RocPlane (V3.0), and <br /> RocTopple(V2.0) by Rocscience. <br /> ' Planar failures can occur when a plane of weakness(such as a joint)daylights in a slope at an angle <br /> steeper than the angle of friction of the joint surface and when the angular range between the strike <br /> of the potential failure plane and the angle of the slope face (termed lateral limits) are less than <br /> ' about 20 to 30 degrees. <br /> Wedge failures can occur when joints within the cut slope intersect and their line of intersection <br /> ' (termed plunge line) daylights in the slope and plunges at an angle steeper than the friction angle <br /> of the joints. In these cases, unstable"wedges"of rock can slide out of the slope. <br /> ' Toppling failures can occur when closely spaced joints within the cut slope are steeply dipping <br /> into the slope face and the lateral limit is less than about 20 to 30 degrees. Flexural toppling can <br /> occur when planes (joints) can slide with respect to each other, ultimately leading to flexure and <br /> ' breaking off of rock slabs that can fall out of the rock face. Direct toppling can occur when two <br /> joint sets intersect to form discrete blocks with plunge lines dipping into the slope and a third low <br /> angle joint acts as a release plane (or sliding plane) for the discrete blocks, allowing them to fall <br /> out of the slope. <br /> For all kinematic failure types described above, Dips considers all planes and intersections within <br /> the data set, which, in this case, includes all 901 discontinuities. The kinematic analysis of the <br /> roadcut used a slope inclination of 80' and an azimuth of 135°. <br /> 1 <br />