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Pile foundations are considered one of the most common foundation solutions for the construction of buildings and structures in difficult geotechnical conditions, including in seismic areas. However, during earthquakes specific processes often occur that negatively affect the interaction of piles with the surrounding soil. Soil liquefaction is one of the most difficult problems in geotechnics. Many historical cases show that buildings and structures on pile foundations are collapsed completely when the surrounding soil liquefies. One of the reasons is the increase in settlement of the foundation after soil liquefaction. Unlike the liquefaction potential assessment, or liquefaction-induced settlement of structures on shallow foundations, which are discussed by many researchers, the settlement of pile foundations after soil liquefaction has not been studied extensively. This paper presents the calculation of the settlement of pile foundations in different cases, with and without taking into account the influence of soil liquefaction, based on the hypothesis that the additional downward loads due to self-compaction of the liquefiable soil layers have an effect on piles. The analysis method in this study refers to the finite element method via PLAXIS 3D software. Finally, a brief comparison of the calculation results in the different considered cases is presented. The comparison shows how much the foundation settlement can increase if the influence of soil liquefaction is taken into account based on the suggested hypothesis. This paper provides a useful calculation and importance of further researches of liquefaction-induced settlement of pile foundations for seismic design.

We present high-temperature ferromagnetism in heavily Fe-doped ferromagnetic semiconductor (FMS) (In1−x ,Fe x )Sb (x = 20%–35%) thin films grown by low temperature MBE. The Curie temperature (T C) of (In1−x ,Fe x )Sb reaches 385 K at x = 35%, which is significantly higher than room temperature and the highest value so far reported in III–V based FMSs. Moreover, large coercive force (H C = 160 Oe) and large remanent magnetization (M r/M S = 71%) have been observed at low temperature (10 K) for an (In1−x ,Fe x )Sb thin film with x = 35%, indicating that the FMS (In1−x ,Fe x )Sb is very promising for spintronics devices.

We study the quantum size effect (QSE) in the spin-dependent electronic structure at the conduction band (CB) bottom (Γ point) of an n-type ferromagnetic semiconductor (In0.92,Fe0.08)As ultrathin films (thickness t = 8–14 nm), by performing magnetic circular dichroism (MCD) spectroscopy in an infra-red photon energy range (E = 0.62–1.8 eV). The t-dependence of MCD peaks are well explained by the optical transitions from the valence band top to the quantized levels at the CB bottom of (In,Fe)As obtained from self-consistent calculations. These findings provide new possibilities of spin-device applications utilizing QSE in nm-scale (In,Fe)As thin films.

Over the past two decades, intensive studies on various ferromagnetic semiconductor (FMS) materials have failed to realize reliable FMSs that have a high Curie temperature (T C > 300 K), good compatibility with semiconductor electronics, and characteristics superior to those of their nonmagnetic host semiconductors. Here, we demonstrate a new n-type Fe-doped narrow-gap III–V FMS, (In1− x ,Fe x )Sb. Its T C is unexpectedly high, reaching ~335 K at a modest Fe concentration (x) of 16%. The anomalous Hall effect and magnetic circular dichroism (MCD) spectroscopy indicate that the high-temperature ferromagnetism in (In,Fe)Sb thin films is intrinsic and originates from the zinc-blende (In,Fe)Sb alloy semiconductor.

We observed supercurrent through an n-type ferromagnetic semiconductor (In,Fe)As. For the purpose we prepared S/F/S (S: superconductor, F: ferromagnet) junctions, which exhibited zero resistance up to 1 µm of junction width with critical current over 1 µA below 1 K. The long reach of the superconducting proximity effect suggests that the induced superconductivity is brought about by spin-triplet paring in (In,Fe)As.