• Proceedings of the Materials Research Society of Korea Conference
• /
• 1994.11a
• /
• pp.156-162
• /
• 1994

The existence of the elastic anisotropic channeling is based on the experimental evidences. The rotating electron pairs orbits play the role of basic bonding orbitals. The abnormal signals from ligand domain and train-membrane in cancer cell, Deformation in fatigue and creep at low stress, con duction, superconduction and semiconduction are all from the new metallic bonding orbital.

• Geomechanics and Engineering
• /
• v.8 no.5
• /
• pp.707-726
• /
• 2015

This paper investigates the time dependent behaviour of Haarajoki test embankment on soft structured clay deposit. Half of the embankment is constructed on an area improved with prefabricated vertical drains, while the other half is constructed on the natural deposit without any ground improvement. To analyse the PVD-improved subsoil, axisymmetric vertical drains were converted into equivalent plane strain conditions using three different approaches. The construction and consolidation of the embankment are analysed with the finite element method using a recently developed anisotropic model for time-dependent behaviour of soft clays. The constitutive model, namely ACM-S accounts for combined effects of plastic anisotropy, interparticle bonding and degradation of bonds and creep. For comparison, the problem is also analysed with isotropic Soft Soil Creep and Modified Cam Clay models. The results of the numerical analyses are compared with the field measurements. The results show that neglecting effects of anisotropy, destructuration and creep may lead to inaccurate predictions of soft clay response. Additionally, the numerical results show that the matching methods accurately predict the consolidation behaviour of the embankment on PVD improved soft clays and provide a useful tool for engineering practice.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.19 no.2
• /
• pp.110-117
• /
• 1999

In order to ultrasonically evaluate creep cavities pure copper samples were subjected to creep test and their microstructures were examined. Ultrasonic velocities. frequency-dependent magnitude spectra and attenuations were measured on a series of copper samples obtained from the different stages of creep test. Velocities measured in three directions with respect to the loading axis decreased and their anisotropy increased as a function of the creep-induced porosity. The anisotropic behavior could be attributed to the progressive change of pore shape and preferred orientation as the creep advanced. The 2% porosity by volume decreased the longitudinal and shear wave velocities by 11% and 4%, respectively. Furthermore, both velocities decreased nonlinearly with the porosity. As the creep damage developed, the magnitude spectra lost high frequency components and their central frequencies shifted to lower values. The attenuation showed almost linear behavior in the frequency range used. Normalized velocity, central frequency shift and attenuation slope were selected as nondestructive evaluation parameters. These results were presented and showed good relations with the porosity content.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2000.09a
• /
• pp.73-78
• /
• 2000

The reinforced soil has been widely used for constructing retaining walls and embankment with steep slope. However, the benefits of soil reinforcing are often-restricted by a lack of good quality backfill material. In this study, plane strain compression tests were carried out to study the effects of preloading on the behavior of geosynthetic-reinforced saturated clay. For the unreinforced and reinforced soil, drained and undrained shearing tests were peformed after anisotropic consolidation in a constant strain rate. A preoading test was carried out by preloading, creep, unloading, aging and undrained shearing after anisotropic consolidation(K=0.3, σ'₃=50 kPa). It was observed that a reinforced clay, Kanto loam, can have a great initial secant modulus in undraind condition by well compaction and over consolidation. The results shown that the increasing of drained strength should be used to apply a large preloading in the case of reinforced clay.

• Korean Journal of Materials Research
• /
• v.4 no.4
• /
• pp.445-452
• /
• 1994

Three-axial deformation behavior of the Zircaloy cladding tube under the irradiation condition of the fuel in pressurized water reactor can be analyzed by the anisotropy in the creep and the irra- diation growth, which depends on the texture parameter. A methodology to evaluate the impact of the anisotropic creep and irradiation growth on the strain in each axial direction of the cladding tube has been proposed. Based on the measured strains after irradiation and predicted ones with the help of a fuel performance analysis code, it is found that a tangential strain of the cladding tube is caused mainly by the creep, whereas a axial strain of the cladding is caused mainly by the irradiation growth but with a considerable contribution of the creep at low irradiation.

• Journal of Magnetics
• /
• v.21 no.1
• /
• pp.25-28
• /
• 2016

In the present study, bulk anisotropic nanocrystalline $SmCo_5$ magnets were prepared by hot deformation. The effect of deformation temperature on the texture and magnetic properties are presented, based on which the mechanism of plastic deformation and texture formation during the hot deformation process is discussed. Our analyses reveal that deformation temperature is one of the most important parameters that determine the texture of $SmCo_5$ grains. We suggest that diffusion creep plastic deformation occurs during hot deformation, which is very sensitive to the energy gain provided by an increase in temperature.