Laserfiche WebLink
Januar.v 15, -7008 <br />21) ff <br />120 f <br />Figure 15. Conceptual 3D Model of Z-Dip Cut #2 Pit Spoil Pile <br />1 qge 25 <br />The methodology used to calibrate the spoil strengths was to incrementally decrease the <br />spoil frictional strength from a peak ot'55° until a failure surface developed in the spoil area of <br />the model similar to what was observed. Spoils were assumed to weaken with disturbance, that <br />is, any zone that reached its peak yield strength would soften to a residual strength of 10' less <br />after 5% inelastic strain (strain-softening relation). Thus, incrementally reducing peak strength <br />Isom 55° to 45° meant also reducing the residual strength from 45° to 35°. This would reproduce <br />the softening behavior of' the spoils necessary to reproduce the localized slope failure <br />mechanism. <br />Results ofthe analysis indicate that the limit of equilibrium ofthe spoil is reached when <br />the spoil friction is about 40°. Table 3 summarizes the results of the analysis. Figure 16 shows <br />Agap ito Associates, Inc.