In this study, the influences of both stirrup spacing and anchorage performance on the residual strength of corroded RC beams are investigated. With the increase of stirrup spacing, the applied load is easily transferred to the anchorage region, and with the increase of the corrosion ratio of rebar, the mechanism of corroded RC beams shifts from beam action to arch action. In the case of non-uniform corrosion of the main rebar, the maximum deviation ratio of the corrosion ratio of main rebars is over 0.9, and the beam suffers flexural failure due to the yielding of rebars in the extremely corroded region. In the case of uniform corrosion of the main rebars, the maximum deviation ratio of the corrosion ratio of main rebars is below 0.9, and there are two situations. If the bottom portions of the stirrups are sufficient, the applied load is restricted in the support span, and the corroded beam presents a flexural failure mode. On the other hand, if the bottom portions of the stirrups are insufficient, the applied load is transferred to the anchorage, and the corroded beam is inclined to suffer bond failure. Moreover, when the beam suffers bond failure, the residual strength depends on the anchorage performance.
Media space is a promising but still immature technology to connect distributed sites. We developed a simple additional function that moved a remote camera forward when a local user approached a display so that the approach was amplified by a remote person's expanding image accompanied by motion parallax. We conducted an experiment in which we observed that a movable camera enhanced social telepresence, which is the feeling of facing a remote person in the same room. Despite the camera's movement, subjects believed that the camera did not move and a zoom-in function expanded the image. Surprisingly, a zoom-in camera that expanded the image as the movable camera did, however, was ineffective probably because of a lack of motion parallax. Although we explained nothing about the camera, most subjects noticed that their walking caused the view's expansion. If a remote person initiated the camera's movement, social telepresence could not be enhanced.
Raising a transition temperature (T c) in organic radical ferromagnets is a desire for material scientists. We investigated the pressure effects on an organic radical ferromagnet 2,5-difluorophenyl-␣-nitronyl nitroxide ͑2,5-DFPNN͒, which has a ferromagnetic transition at 0.45 K. The hydrostatic pressure effects were investigated through measurements of ac magnetic susceptibility ͑͒ up to Pϭ1.7 GPa, heat capacity (C p) up to Pϭ1.5 GPa, and powder x-ray diffraction up to Pϭ4.7 GPa. Furthermore, ac magnetic susceptibility under nonhydrostatic pressure was also measured in the pressure region up to 10.0 GPa. As for 2,5-DFPNN, we observed the pressure-induced enhancement of T c as dT c /dPϭ7.9ϫ10 Ϫ2 K/GPa ͓T c (Pϭ1.5 GPa) ϭ0.57 K͔, while other prototypes, the  phase of p-NPNN and p-Cl-C 6 H 4-CHvN-TEMPO show the negative pressure effects. The results for the C p and the crystal structural analysis suggest that the magnetic dimension of the short-range order developing above T c transforms from one dimension ͑a axis͒ to two dimensions ͑ac plane͒ under high pressure. This increase of the magnetic dimension probably promotes to increase T c. The ferromagnetic signal of , however, decreases with increasing pressure, and finally disappears for Pу5.0 GPa. The decrease seems to originate from the decrease of the ferromagnetic interaction along the b axis. Similar instability of organic ferromagnetic long range order against pressure has been observed for the  phase of p-NPNN and p-Cl-C 6 H 4-CHvN-TEMPO.
In this study, the bond behavior of corroded reinforced concrete (RC) was investigated by conducting pull-out tests on RC specimens with different corrosion crack widths. The confinement stress of concrete was evaluated by an expansion simulation using a non-explosive demolition agent, from which a confinement stress equation for RC with corrosion cracking was proposed. Bond strength linearly decreased with decreasing confinement stress in the concrete. The rate of decrease was independent of longitudinal corrosion crack width at the concrete surface, cover thickness, and reinforcement diameter. Furthermore, from the relationship between bond strength and confinement stress in concrete, equations for predicting bond stress and slip curve were proposed. Overall, the predicted values agreed well with the experimental results of other studies.
Surface analysis was performed by a new analytical method, grazing-exit electron probe microanalysis (GE-EPMA). At grazing-exit (small x-ray take-off) angles, only characteristic x-rays emitted from the near-surface regions are measured because of strong absorption and refraction effects at the surface. The exit angle was carefully determined using a stepping motor (with a minimum step angle of 0.018 • ), and the emergent x-rays were measured by an energy-dispersive x-ray detector and analyzed with a multi-channel analyzer (MCA). A computer controlled both the stepping motor and the MCA so that the exit-angle dependence of the characteristic x-ray intensities was measured automatically. The angle-dependent curve for a thin cobalt film (5 nm thick) deposited on a silicon wafer indicated that the cobalt x-rays predominated at grazing exit angles, demonstrating that high surface sensitivity was obtainable under these conditions. The results from a polished stainless-steel sample revealed chromium enrichment at grazing exit angles, which corresponds to a thin passivation layer of chromium oxide at the surface. Both sets of data suggest that GE-EPMA is a promising technique for localized surface analysis.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.