Numerical analysis of pile group within moving soils

Abstract

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] A coupled soil-pile interaction analysis method for pile groups within moving soil is proposed and implemented in a new computer program MU-PILE-GROUP. Results of evaluations described in this dissertation indicate that the response of pile groups subjected to soil movement can be accurately predicted using MU-PILE-GROUP. Results of analyses presented also show that modifications to commonly used p-y and t-z models (p-multipliers, y-multipliers and t-multiplier) are required to produce close matches between the predicted response from MU-PILE-GROUP and measured response from a series of large-scale laboratory tests. The relationship between these multipliers and spacing ratio and pile batter angle were investigated to improve understanding of soil-pile interaction and to provide recommendations for use of MU-PILE-GROUP. A range of p-multipliers varying from 0.15 to 1.8 and a range of y-multipliers varying from 0.33 to 1 are required for the Reese sand model to produce close matches with measured lateral performance. p-multipliers required to match measured performance decrease with increasing pile spacing perpendicular to the direction of soil movement. y-multipliers required to match measured performance increase with increasing spacing perpendicular to the direction of soil movement. p-multipliers required to match measured performance also increase with increasing pile batter angle. The predicted axial performance reasonably matches the measured axial response for most upslope piles.