Response of normally consolidated kaolin clay under irregular cyclic loading and comparison with predictions from the accumulation procedure

D. Zografou, S. Gourvenec, C. D. O'Loughlin
2018 Geotechnique  
The accumulation procedure on contour diagrams of shear strain is used in geotechnical design to account for the effect of cyclic loading on offshore foundations. In this paper, contour diagrams of maximum shear strain are presented based on a series of stress-controlled, symmetrical and non-symmetrical, cyclic direct simple shear tests on normally consolidated kaolin clay that can be used to re-examine the extensive database of model testing in kaolin clay. It is shown that the failure under
more » ... n-symmetrical cyclic loading can be defined at a higher maximum shear strain than under symmetrical loading, offering potential opportunities for reducing foundation sizes for structures that are less sensitive to displacement. Staged tests with parcels of uniform amplitudes have been also performed to compare the measured shear strains with the values predicted by the accumulation procedure. It is shown that the accumulation procedure predicts the strain measured in the symmetrical staged tests well but overpredicts shear strains measured in the non-symmetrical staged tests. Keywords Cyclic loading; normally consolidated clay; direct simple shear test List of notation a fitting parameter for contour diagram of γmax b fitting parameter for contour diagram of γmax c fitting parameter for contour diagram of γmax CSR cyclic stress ratio DSS direct simple shear e0 void ratio (as extruded) f frequency Gcyc cyclic shear modulus Gs specific gravity Published in Géotechnique τmax maximum shear stress τmax,f cyclic shear strength Published in Géotechnique https://doi.
doi:10.1680/jgeot.16.p.340 fatcat:c3pzl34eeja6ba6wenvuajll2a