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In the conventional French railway substructures, a layer namely interlayer was created naturally by the interpenetration of ballast and subgrade. The lower part of this interlayer is characterized by a matrix of fines with inclusion of coarse grains in it. Moreover, the coarse-grain content is decreasing over depth. In this study, the effect of volumetric content of coarse grains f v (volumetric ratio of coarse grains to the whole sample; grain size > 2 mm) on the mechanical behavior of the lower part interlayer soil was investigated by carrying out monotonic triaxial tests. The results showed that increasing the volumetric content of coarse grains f v led to more significant dilatancy. The shear strength also increased with the increase of f v and the increasing trend appeared to be much more significant when f v >20%. Examination of the variations of peak deviator stress with f v revealed the existence of a characteristic value of f v - cha  ≈ 27% that separates two zones with different coarse-grain effects: a fine-fine contact dominating zone when f v  ≤ 27% and a grain-grain contact dominating zone when f v  > 27%. To clarify the observed phenomena, X-ray microcomputed tomography (μCT) scans were performed on the as-compacted samples, allowing the coarse-grain distribution inside the as-compacted sample to be visualized. It was found that when f v ranged from 0% to 10%, the skeleton of the sample was mainly constituted by fines with the coarse grains floating in the fines matrix. By contrast, when f v reached 20%, the coarse grains formed some aggregates but the fine-fine contacts were still dominating. When f v increased up to 35%–45%, the skeleton of the sample turned to be dominated by the coarse grains. This suggests that the characteristic volumetric content of coarse grains identified through monotonic triaxial test results corresponds to the transition of soil fabric from fine-fine contacts to grain-grain contacts. [ABSTRACT FROM AUTHOR]

Motivated by the recently observed anomalous large dimuon charge asymmetry in neutral B decays, we study the effects of the anomalous tensor couplings to pursue a possible solution. With the constraints from the observables ∅sJ/ψ(∅,fo), assl and ΔMs, the new physics parameter spaces are severely restricted. We find that the contributions induced by the color-singlet or the color-octet tensor operators are helpful to moderate the anomaly in B0s - B0s mixing. Numerically, the observable assl could be enhanced by about two orders of magnitude by the contributions of color-singlet or color-octet tensor operators with their respective nontrivial new weak phase ∅T1 = 41°±35° or ∅T8 = -47° ± 33° and relevant strength parameters |gT1| = (2.89 ± 1.40) × 10-2 or |gT8| = (0.79 ± 0.34) × 10-2. However, due to the fact that the NP contributions are severely suppressed by the recent LHCb measurement for ∅J/ψ(∅,fo)s, our theoretical result of assl is still much smaller than the central value of the experimental data. [ABSTRACT FROM AUTHOR]