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<br />STABILITY ANALYSIS RESULTS: <br />' The UTEXAS2 analytical modelling program, analysis method and <br />program options were described in previous sections of this report. <br />As noted above, two sections were considered in the present <br />' analysis. In each case several automatic and individual search <br />trials were performed, varying the initial search input data, to <br />assure that the minimum factor of safety was found. The data for <br />subsurface and modelling conditions have been also been described <br />' elsewhere. Plates 36 and 37 of the Appendix present the profile, <br />parameters used and the resulting safety factor for respective <br />shallow and deep critical shear surfaces at section A-A. Plate 38 <br />' of the Appendix presents the profile, parameters used and the <br />resulting safety factor at section C-C. Previous discussions have <br />emphasized the fact that piezometric levels measured at discrete <br />' depths within the pile have, in some cases, varied dramatically <br />during the relatively short 18-day observation period. <br />Consequently, after obtaining safety factors for the two sections <br />based on the highest observed piezometric measurements, piezometric <br />' surface sensitivity analyses were performed by increasing the <br />piezometric head or pore pressures until a safety factor of '_.5 was <br />returned. This was undertaken in an effort to establish critical <br />' target depth measurements for each of the recently installed <br />piezometeis. Plates 39 and 40 of the Appendix present the critical <br />shear surface and resulting safety factor for the two (shallow and <br />' deep} sensitivity analyses at section A-A. Plate 41 of the <br />Appendix presents the critical shear surface and resulting safety <br />factor for the sensitivity analysis at section C-C. During the <br />sensitivity analyses for both sections it was found that pile <br />' stability was extremely sensitive to slight increases in the <br />piezometric surface deep within the pile. As noted in previous <br />sections of this report this deep portion of the piezometric <br />' surface was modelled on a 12-degree slope which was conservatively <br />modelled as a projection to the surface of the piezometric surface, <br />based on measured piezometric data. There is no substantiating <br />evidence to support this extrapolation. Piezometers located <br />' further toward the deeper portions of the pile would be required to <br />provide such evidence. The following table summarizes safety <br />factor results for each of the two sections analyzed: <br />1 <br />1 <br /> <br /> <br /> <br />28 <br />1 <br />