Methods of Estimating Settlement

Methods of predicting how much a structure will settle because of the compression of saturated soil under the structure are examined, based on both theoretical considerations and experimental data. Concepts, recently developed, of the stress-strain behavior of saturated cohesive soils are an especially important part of this examination. The effective stress path settlement method is proposed, based on its ability to (1) handle types of settlement problems for which other methods are inadequate, (2) help the engineer to estimate the immediate and consolidation settlement components from a single consistent analysis, and (3) offer considerable insight into the settlement problem under study. Uncertain steps in all methods of settlement analysis include the development of an accurate picture of the subsoil strata in a particular problem, the determination of the magnitude and distribution of the surface load and of the increments of the total stress that they induce in the subsoil, and the influence of sample disturbance on stress-strain data obtained in the laboratory. Additional data from models and field jobs and the interpretation of these data would enhance knowledge of the settlement phenomena.