One-Dimensional Consolidation Test with Pore Pressure Measurements — An Accelerated Procedure

Abstract

Abstract Consolidation properties of cohesive soils are often determined using the controlled-strain loading (CSL) consolidation test. It was well recognized in the literature that the consolidation properties, such as compression index (Cc), coefficient of consolidation (cv), and preconsolidation pressure (σc′), depend on the axial strain rate adopted for conducting the CSL test. Fixing the appropriate axial strain rate is often a challenge in CSL tests. The conventional incremental load (IL) consolidation test suffers from the limitation that it takes long time to complete the test. In the present study, an accelerated IL consolidation testing procedure with pore water pressure measurements is developed in an attempt to overcome the limitations of the CSL and conventional IL consolidation tests. The duration of the IL is controlled such that the subsequent IL is applied once the excess pore pressure dissipates to 15 % of the total applied stress (pore pressure ratio, Ru, is 0.15). The testing procedure is validated by performing a series of experiments on six reconstituted and four intact soil samples. The consolidation parameters obtained from the proposed method compares very well with conventional IL test as well as with the CSL consolidation test, suggesting its validity. The proposed method is about 3 times faster when compared with the standard CSL test. Therefore, the proposed method is a viable alternative to the CSL consolidation test.