Method of Calculating Long-Term Creep Settlements

A practical method of estimating the rate of creep and the time-settlement behavior of a footing on clay under three-dimensional conditions is described. This method, termed the extended stress path method is an extension of earlier methods for calculating immediate and consolidation settlement, and is applicable to footings subjected to normal working loads. The method is restricted to post-consolidation creep and cannot be applied to creep which may occur under undrained conditions. The results of model footing tests are presented and the effects on the rate of creep of factors, such as the ratio of footing diameter to layer depth, and the loading intensity on the footing, are considered. Comparisons are made between the observed creep rate and time-settlement behavior of the model footings and the values calculated from the proposed approach, and reasonable agreement is found.