An analytical model for radial consolidation prediction under cyclic loading

Abstract

The excess pore pressure increases under undrained cyclic loading which cause decrease in effective stress followed by possible failure in the soft soil. With the inclusion of vertical drains radial drainage allows quick dissipation of excess pressure during cyclic loading and thereby failure of foundation soil may be avoided. The present study aims for analytical closed-form investigation on soft cohesive deposit under radial flow consolidation through vertical drains with no smear when subjected to long-term rapid cyclic loading. The mathematical formulation of pore pressure including degree of consolidation under cyclic loading is developed by using Green’s functions technique. Results obtained from the proposed formulation are in good agreement when compared with published field data which confirms its correctness to predict consolidation under cyclic loading. Once the proposed model is validated, it is applied to investigate the effect of vertical drains on variation of pore pressure ratio with number of loading cycles. The findings indicate that the pore water pressure generates slowly at the outermost boundaries of the vertical drains for initial number of loading cycles. The magnitude of pore water pressure accumulation increases and then dissipates for higher number of loading cycles. The variation of degree of consolidation for different frequencies of a unit cell of a prefabricated vertical drain is also furnished. © 2021 Techno-Press, Ltd.