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Martin Marietta Materials <br />Spec -Agg 2015 Annual Report <br />Table 2: Representative Quarry Wall Orientations <br />New Wall Designation <br />Former Wall <br />Designation <br />Slope Angle(,) <br />Slope Direction of Wall (Z) <br />East Wall 1 <br />East Wall <br />45° <br />242° <br />East Wall 2 <br />(not considered) <br />45° <br />270° <br />Northeast Wall 1 <br />Northeast Wall <br />35° <br />175° <br />Northeast Wall 2 <br />(not considered) <br />45° <br />225° <br />Northeast Wall 3 <br />(not considered) <br />45° <br />176° <br />Northwest Wall <br />Northwest Wall <br />35° <br />151' <br />West Wall 1 <br />West Wall <br />45° <br />091 ° <br />West Wall 2 <br />West Wall <br />45° <br />120° <br />West Wall 3 <br />West Wall <br />45° <br />091 ° <br />Southwest Wall 1 <br />Southwest Wall <br />45° <br />016° <br />Southwest Wall 2 <br />Southwest Wall <br />45° <br />036° <br />South Wall <br />(not considered) <br />45° <br />000° <br />Southeast Wall <br />Southeast Wall <br />45° <br />335° <br />Notes: <br />1: Slope angles are measured relative to the horizontal. <br />2: Slope orientations are presented as dip directions measured from true north (0 °). <br />6.3 Friction Angle <br />A representative angle of friction (+ + ►) = 33° was used for our kinematic analysis, where " +" is the basic <br />friction angle and "P' is the surface roughness angle (Hoek and Bray, 1977). The surface roughness <br />angle is the angle between the basic plane of the joint and the planes representing the surface of ripples <br />or undulations of the joint surface. This value was based on the results of the direct shear testing <br />performed as part of the 2003 geotechnical investigation (L &A, 2003). The test results produced only a <br />basic friction angle, +, and results indicated that the basic friction angle of the discontinuities ranged from <br />13.7° to 49.3° with a mean value of 28 °. These results do not include the two direct shear tests <br />conducted on samples with clay material along the foliation plane, which produced an average friction <br />angle of 50. A generally accepted and conservative value of 50 was selected for the surface roughness <br />angle, "P. <br />6.4 Kinematic Analysis <br />We performed kinematic structural discontinuity analyses for each of the representative quarry wall <br />orientations presented in Table 2. The analyses were performed to evaluate potential rock slope failure <br />modes controlled by planar rock mass discontinues based exclusively on the geometric relationships of <br />the discontinuities measured. Potential rock slope failure modes include sliding of wedges formed in the <br />slope by the intersection of two discontinuity planes, sliding of rock blocks along a single planar <br />discontinuity, and toppling rock blocks. The computer program DIPS 6.016 (Rocscience, 2014) was used <br />for the kinematic stability analysis. Inputs for the analyses include the following: <br />February 25, 2015 Page 10 Lachel & Associates, Inc. <br />Project 14364006.00 02015 All Rights Reserved <br />