Discussion of “Lateral Pipe-Soil Interaction in Sand with Reference to Scale Effect” by P. J. Guo and D. F. E. Stolle

Abstract

The discusser states that in addition to the authors' update of extant guidelines on the resistance to lateral movements of pipes buried in sand, the scale effects should be examined more closely. In particular, the discusser questions how the sand grains used in finite-element analysis could be called 'purely frictional material,' as these grains can be deformed and crushed. The discusser also notes that the sand grain properties include both cohesion c and Young's modulus E, which have dimensions of stress. In applying dimensional analysis (Buckingham's II theorem) to the test results, the discusser notes that the size effect addressed by the authors is really the effect of changing c and E at both the same time and by the same factor. With no firm conclusion as to what proportion of the influence is shared by c versus E, the discusser suggests a more appropriate title for the paper, should cohesion c be shown to have greater influence. The proposed new title would be Lateral Pipe-Soil Interaction in Sand with Reference to the Effect of Cohesion.