In many cases, the decision-maker may need an expert's judgment to sharpen his/her uncertainties with respect to the likelihood of each state of nature.
The first reason is that the calibrations were performed using the variability of the measurements of unit side resistance, rather than the variability of predictions for unit side resistance.
Several alternative methods are provided because of difficulties that can arise with reliable sampling and code reduction bilboquet testing of weak rock.
The Service I Limit State shall be used when evaluating lateral deflection.Units, American Association of State Highway and Transportation Officials, Fourth Edition with 20 Interim Revisions.Kate Moran by, kate cadeau adler Moran on September 3, 2017 11, summary: Flat interfaces often use weak signifiers.Use of undrained shear strength values established from approximations or from index tests such as hand-held penetrometer tests, Torvane tests, or Standard Penetration Tests will introduce additional variability and uncertainty into the design that is currently not reflected in the resistance factors provided.
The appropriate tip resistance shall be established for the soil/rock located between the tip of the shaft and a distance of 2D below the tip of the shaft.
The reduction factor shall be determined and included as part of the nominal unit side resistance by the Geotechnical Section.
Notice that those characteristics are also just good, basic UX design best practice: visual simplicity, external consistency, clear visual hierarchy, and contrast.Murphy (2011 MoDOT Transportation Geotechnics Research Program: Drilled Shaft Axial Load Test Program Data Report, Missouri Department of Transportation, OR11.XXX, XXX.The E and I values used in the above equation shall also be used for longitudinal force distribution annales concours ecole d architecture calculations.While Neq is not strictly an SPT N -value, its use is consistent with current MoDOT practice and, since it was used as the basis for calibration of the methods of this article, is appropriate for use in design.The second reason is that the empirical data upon which the resistance factors were derived were based on load tests performed on shafts that were not necessarily constructed following current MoDOT construction specifications.Resistance factors to be applied to the nominal resistance values (qs) determined according to the provisions of this article shall be established from Figure.1 based on the coefficient of variation of the mean equivalent SPR N- value.Settlement Resistance Factors for t-z Method for Drilled Shafts in Weak Rock from Texas Cone Penetration Test Measurements Settlement resistance factors to be applied to side resistance for shaft segments through weak rock shall be determined from Figure.7 based on the coefficient of variation.Thus, a decision tree is needed.