Discussion of “Interaction between Laterally Loaded Pile and Surrounding Soil” by Hai Lin, Lusu Ni, Muhannad T. Suleiman, and Anne Raich

Abstract

First of all, the discussers would like to congratulate the authors for producing a significant amount of good quality data, always useful for checking assumptions and methods. In particular, the use of tactile pressure sheets, despite some shortcomings, opens new possibilities for measurements of stresses in some special conditions and applications. However, a number of points in the paper need further clarification and/or complementation, as stated as follows: 1. Concerning the Broms’s (1964) method in the case of sands, it is said in the paper that it assumes that the pile rotates around its tip and the ultimate soil pressure equals three times the passive pressure. This is not strictly true. In fact, Broms (1964) clearly indicates (Fig. 1) that the center of rotation is not at the toe of the pile. Broms (1964, p. 137) says that “Failure takes place when the pile rotates as a unit around a point located below the ground surface.” Also, “high negative earth pressures develop close to the toe of the laterally loaded pile and it has been assumed for the purpose of analysis that this pressure can be replaced by a concentrated load as shown in Fig. 5(b)” (Fig. 2). In other words, Broms did not assume that the pile rotates around its toe, this was a simplification to derive a simple solution. 2. The authors claimed the measurement of circumferential stresses for the first time. Although their contribution is very significant because they have made a detailed picture of those stresses, reference should have been made to Bierschwale et al. (1981), who measured the stresses around the periphery of a drilled shaft, 915 mm in diameter and 4.6 m in length, embedded into a predominantly clay soil. In addition to installing cells in the vertical direction, three total stress cells were placed in