Study on Prediction of Pore Pressure Development without Membrane Compliance Based on Cm.

In undrained triaxial tests, membrane penetration varies with the change of effective confining pressure. Membrane compliance correction is a necessary step to accurately obtain the dynamic characteristics of soils in geotechnical tests. In this paper, a real-time instrument compensation equipment was adopted to eliminate membrane compliance The influence of membrane compliance on pore pressure was explained from experimental perspective, and a two-stage formula was proposed to establish the relationship between the optimized membrane correction coefficient Cm and the normalized pore pressure U/σ0′. C, which is the constant value of Cm in the stationary segment, is analyzed under different confining pressures, relative densities, consolidation ratios, and gravel contents, and the power function of C with the characteristic particle size d50 is proposed. Based on Cm, a series of predictions of pore pressure development without membrane compliance are implemented, which are basically consistent with the actual experimental results. The method to predict the pore pressure development without membrane compliance based on Cm is accurate and effective, and a large amount of experimental workload can be reduced for practical engineering applications. [ABSTRACT FROM AUTHOR]