WES Theoretical Manual, Appendix A: Example Problems

Appendix A works through example problems for cells on bare rock and on other foundations. The first example starts with a saturated cell, lists the data for the fill and the sheet piles, and takes the reader step by step through the interlock tension, the crosswall tension, and the factors of safety.

For instance, the example uses an ultimate interlock strength of 16.0 kips per inch, takes the earth pressure coefficient as 1.2 times the Rankine active value, and computes the factor of safety against bursting for cells of different widths. The comparison shows how the factor of safety falls as the cell gets wider, since a wider cell carries more fill pressure on the same sheeting.

Working through these examples is the best way to learn the manual's methods, and they make a useful model for how to organize a design calculation so a reviewer can follow every step. The appendix also includes a table of factors for converting units.