Cover Image

Not for Sale



View/Hide Left Panel
Click for next page ( 48


The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement



Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 47
47 20 0.16 45 Number of Pile-Cases log-normal Relative Frequency distribution 15 mx = 1.626 0.12 40 0.24 mlnx = 0.384 lnx = 0.444 normal distribution 10 0.08 35 x = 0.797 0.2 5 0.04 30 Number of Pile-Cases Relative Frequency log-normal 0.16 0 0 25 distribution 0 0.5 1 1.5 2 2.5 >3 mlnx = 0.100 mx = 1.158 20 0.12 Ratio of Static Load Test Results over the Pile Capacity lnx = 0.295 Prediction using the CAPWAP method normal distribution 15 Figure 30. Histogram and frequency distributions for all 0.08 x = 0.393 EOD (125) CAPWAP pile-cases in PD/LT2000. 10 0.04 5 to require 100% of drilled shafts be postconstruction tested for major defects, as this ensures total quality at little addi- 0 0 tional cost. 0 0.5 1 1.5 2 2.5 >3 Ratio of Static Load Test Results over the Pile Capacity Prediction using the CAPWAP method 3.4 RECOMMENDED RESISTANCE FACTORS Figure 32. Histogram and frequency distributions for all 3.4.1 Overview BOR-last (162) CAPWAP pile-cases in PD/LT2000. This section presents all the relevant resistance factors and recommendations for the AASHTO LRFD deep foundation 3.4.2 Static Analysis of Driven Piles design specifications. Tables 25 through 30 are based on Table 25 presents the recommended resistance factors to be material provided in the previous sections and are presented used with static analysis of driven piles under compression, as in an integrated format according to similarity of calculated well as the individual efficiency factor of each method, which factors, extent of data on which the factors were based, and indicates the method's relative economic merit. The design relevant issues that have to be addressed as comments to the methods should be applied based on soil parameters obtained recommended values. The factors are divided based on pile via a subsurface exploration program with the detailed appli- redundancy as discussed in section 2.7.5. cation and correlations as outlined in Tables 6, 7, 8, and 19 and The recommended resistance factors represent the most further detailed in Appendices B and D. Table 26 presents the significant attempt to date to develop LRFD code for deep recommended factors to be used under tension (pullout) con- foundations based on empirical data. ditions, analyzing the skin friction in the same way as it was for compression loads, excluding tapered piles. 25 log-normal 20 0.2 distribution 20 0.16 Number of Pile-Cases log-normal Number of Pile-Cases Relative Frequency Relative Frequency mlnx = 0.011 15 distribution 0.15 lnx = 0.366 15 mx = 1.084 0.12 mlnx = 0.330 mx = 1.656 normal distribution 10 lnx = 0.549 0.1 normal distribution 10 0.08 x = 0.431 x = 1.199 5 0.05 5 0.04 0 0 0 0 0 0.5 1 1.5 2 2.5 >3 0 0.5 1 1.5 2 2.5 3 Ratio of Static Load Test Results over the Pile Ratio of Static Load Test Results over the Pile Capacity Capacity Prediction using the GRLWEAP method Prediction using the Energy Approach method Figure 33. Histogram and frequency distributions for Figure 31. Histogram and frequency distributions for all EOD default value GRLWEAP pile-cases, (99), data EOD (128) Energy Approach pile-cases in PD/LT2000. provided by GRL (see Hannigan et al., 1996).