Load Transfer in Earth and Rockfill Dams

An interpretation of instrumentation data obtained from several major rockfill dams revealed that various modes of load transfer and changes in modes may occur in an embankment during its lifetime. Load transfer may significantly influence the characteristics of embankment behavior—settlements and cross-valley displacements, strains, pore-water pressures, and earth pressures. The effects of load transfer on embankment behavior are a function of the stiffness of the core materials in conjunction with the settlement characteristics of the shell materials. The instrumentation used in the study consisted of inclinometers and crossarms that were installed during construction of the embankments. The settlement data were expressed in terms of strains or in terms of a percentage of the surface increment of settlement. Changes in strain at depth within certain intervals of time reflected changes in stress. A need for greater use of instrumentation exists of the type which, during both the construction and post-construction periods, reflects the mass behavior of the various zones that comprise the dam.