**Calculation of Interaction Diagrams for Precast, Prestressed Piles, 2nd Edition (PD-01-15)**

This free eBook provides context and instructions for the use of the 2015 revised version of the Microsoft Excel workbook to compute pile stresses, plot interaction diagrams, and compute lifting points of precast concrete piles. There is no cost for downloading this publication. However, registration is required so that users can be contacted when updates or revisions to the workbook are necessary. The Appendix of this eBook contains detailed instruction and solved example problems using the 2015 workbook. Examples are also solved using Mathcad to validate the workbook solution, and a table of results compares the two methods. Page iv of this manual provides link to a password protected portal for software download.