2011/02/01 by J. Yang, J. YANG, B.B. DAI +1 · 75 citations
Chemistry · Engineering · Environmental Science · #Chemistry #Classical mechanics #Computer science #Constant (computer programming) #Geology #Geotechnical Engineering and Soil Mechanics #Geotechnical Engineering and Underground Structures #Geotechnical engineering #Granular material #Landslides and related hazards #Macroscopic scale #Materials science #Mechanics #Particle (ecology) #Physics #Scale (ratio) #Statistical physics #Steady State theory #Steady state (chemistry)
paper · open access · doi:10.1680/geot.8.p.129
published in Géotechnique 61(2), 175-183 (ICE Publishing)
openalex publication_date 2011/02/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/02
Whether the so-called quasi-steady state is a real material response is a fundamental yet controversial question in the study of undrained shear behaviour of sand. An attempt is made here to clarify the question from a micromechanical viewpoint by means of a grain-scale modelling technique combined with statistical analyses. The study shows that the quasi-steady state is a real behaviour rather than a test-induced phenomenon; it is a transition state, and can be regarded as the result of spatial rearrangement of discrete particles sheared under the constant-volume condition. The quasi-steady state has distinct features that make it different from the steady state at both the macro scale and micro scale. During the loading process, the average number of contacts per particle decreases with strain until the quasi-steady state emerges, and after that it increases gradually to an approximately constant value at large deformations associated with the steady state. This result suggests that the loss of contacts is most pronounced at the quasi-steady state. The study also shows that the contact normal forces and particle rotations play a major role in the deformation process, whereas the contributions of contact tangential forces and particle sliding appear to be minor.