Lateral-Load Tests on 25.4-mm (1-in.) Diameter Piles in Very Soft Clay in Side-by-Side and In-Line Groups

Studies were made to investigate efficiencies of pile groups under lateral loading. The loading was in one direction at slow displacement rates approaching static conditions. The test piles were 25.4-mm (1-in.) diameter tubes open-ended, with penetrations of two, four, six, or eight diameters. Tests were made on single piles and on three- and five-pile groups with clear spacings of 0.5, 1, 2, 3, and 5 diameters in side-by-side or in-line arrangements. The tests were run in a very soft clay with a moisture content of 59% and a shear strength of 2 kPa (42 psf).

Summaries are given of efficiencies of 20 combinations of pile numbers, penetrations, arrangements, and clear spacings. Efficiencies are given for individual piles in a pile group as well as for the entire group. Distances from the soil surface to the load resultant on individual piles and to the load resultant on the total group are also given.