scope:

Purpose and Scope of Study

The purpose of this study is to determine which of the existing p-y methods is the most accurate in matching a large population of well-documented field tests from numerous test sites. Model tests are excluded from this study since they do not model effective stresses correctly. All methods considered are straightforward to apply, using pile and soil data that are readily available to the practicing engineer, because the intention of this study is to recommend a design procedure.

The results of laterally loaded pile tests in sand were obtained from different locations where sand densities and pile geometry and material composition vary. The modeling techniques were then applied to each test to predict the behavior of the pile, which was then compared with the test results. A statistical comparison was then made to determine which of the criteria is the most accurate based on all of the field tests. The particular aspects of pile behavior investigated are pile-head deflection, value of maximum moment and position of maximum moment under conditions of monotonic, static loading and of cyclic loading. The most accurate of the existing criteria was then modified in a way to achieve a closer fit with the body of test results. This modified method is recommended to the American Petroleum Institute for inclusion into RP2A. Finally, the sensitivity of predicted pile behavior to errors in the modified criterion was evaluated and design aids are presented.