Consolidation settlement due to ramp loading

Abstract In one-dimensional consolidation analysis, it is generally assumed that the load is applied instantaneously. In reality, the load is applied over certain duration which has an effect on computations. This paper presents some ramp loading tests using a standard oedometer to support some simple theoretical developments. It is shown that during ramp loading, the plot of settlement v. time, normalized with respect to the end of ramp loading values, is relatively independent of the clay type and loading duration. This normalized plot can be used to predict the settlement pattern during the construction period and the coefficient of consolidation, using a single measurement at any time during construction. Post-construction settlements are predicted separately by assuming a sinusoidal initial pore water pressure distribution at the end of the construction period that is applied instantaneously. Laboratory oedometer test data show very good agreement with the theory.