• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.4
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• pp.923-932
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• 1994

The studies on the bearing capacity of shallow and deep foundations have been made in various fields and formulas for various failure mechanisms have been presented. But, for these models, the method of classification with foundation depth has been obscure and bearing capacity factors have not been uniformly applied. An experiment was performed, in plane strain conditions, with ground model made of carbon rods. The failure mechanism of foundation and ultimate bearing capacity with foundation depth were observed. Based on experimental results the classification between shallow and deep foundations by failure shape was tried. Various present failure mechanisms of foundation were verified through the experiment.

• Journal of the Earthquake Engineering Society of Korea
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• v.6 no.4
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• pp.1-6
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• 2002

The structural safety required in general design is to be proved with safety factors provided for structural members in elastic range. But, for the safety requirement in the earthquake resistant design, a specific ductile failure mechanism in plastic range should be verified according to the structural configuration. Therefore such verifications should be done in the preliminary design stage by comparing various design alternatives. In the main design stage only a confirmation of the ductile failure mechanism is required. In this study typical roadway bridges are selected and analysis models are presented for the preliminary and main design. For the two models, vibration periods and mode shapes are compared and the multi-mode spectrum method is applied to determine failure mechanisms. The failure mechanisms obtained with the two models are compared to check the properness of the model used for the preliminary design, which may well be used as an earthquake resistant analysis model in practice.

• Journal of Power Electronics
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• v.14 no.6
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• pp.1272-1280
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• 2014

This paper presents solutions for fault detection and diagnosis of two-level, three phase voltage-source inverter (VSI) topologies with IGBT devices. The proposed solutions combine redundant standby VSI structures and contactors (or relays) to improve the fault-tolerant capabilities of power electronics in applications with safety requirements. The suitable combination of these elements gives the inverter the ability to maintain energy processing in the occurrence of several failure modes, including short-circuit in IGBT devices, thus extending its reliability and availability. A survey of previously developed fault-tolerant VSI structures and several aspects of failure modes, detection and isolation mechanisms within VSI is first discussed. Hardware solutions for the protection of power semiconductors with fault detection and diagnosis mechanisms are then proposed to provide conditions to isolate and replace damaged power devices (or branches) in real time. Experimental results from a prototype are included to validate the proposed solutions.

• Structural Engineering and Mechanics
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• v.2 no.2
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• pp.141-156
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• 1994

In this paper, the effect of material elasticity was evaluated through a simple model as proposed by Wang and Yu (1991), for yield mechanisms of a cantilever beam under tip pulse loading. The beam was assumed rigid-perfectly plastic but instead of the usual fully clamped constraints at its root, an elastic-perfectly plastic rotational spring was introduced there so the system had a certain capacity to absorb elastic energy. Compared with a rigid-perfectly plastic beam without a spring root, the present beam-spring model showed differences in the initial plastic hinge position and the minimum magnitude of the dynamic force needed to produce a plastic failure. It was also shown that various failure responses may happen while the hinge travels along the beam segment towards the root, rather than a unique response mode as in a rigid perfectly plastic analysis.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.217-220
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• 2005

The designer has difficulty due to inadequacy of provisions in the domestic design code and lack of understanding for behavior of D-region. The reinforced concrete pier coping consists of various failure mechanisms as the crushing or splitting from compression concrete, and shearing failure under the loading plate. However, predicting those failure mechanisms is very difficult. In this study, reinforced concrete pier coping is analyzed and designed by using strut-tie model. Adequacy for the application of strut-tie model is verified by comparison with the way used in current design practice. The results show that strut-tie model can be a rational and an economical design than current conventional design methods.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.11a
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• pp.135-142
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• 2000

A framework alternative to that of classical slope stability analysis is developed, wherein the soil mass is treated as a continuum and in situ soil stresses and strengths are computed accurately using inelastic finite element methods with general constitutive models. Within this framework, two alternative methods of stability analysis are presented. In the first, the strength characteristics of the soil mass are held constant, and the gravitational loading on the slope system is increased until failure is initiated by well-defined mechanisms. In the second approach, the gravity loading on the slope system is held constant, while the strength parameters of the slope mass are gradually decreased until well-defined failure mechanisms developed. Details on the applying both of the proposed methods, and comparisons of their characteristics on a number of solved example problems are presented.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.373-376
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• 2004

The designer has difficulty due to inadequacy of provisions in the domestic design code and lack of understanding for behavior of D-region. The rectangular shaped corbel consist of various failure mechanisms as the crushing or splitting from compression concrete, and shearing failure under the loading plate. However, predicting those failure mechanisms is very difficult. In this study, rectangular shaped corbel is analyzed and designed by using strut-tie model. Adequacy for the application of strut-tie model is verified by comparison with the way used in current design practice. The results show that strut-tie model can be a rational and an economical design than current conventional design methods.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.213-216
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• 2006

The designer has difficulty due to inadequacy of provisions in the domestic design code and lack of understanding for behavior of D-region. The reinforced concrete pi(${\pi}$)-shaped RC rahmen bridge consists of various failure mechanisms as the crushing or splitting from compression concrete, and shearing failure under the loading plate. However, predicting those failure mechanisms is very difficult. In this study, the pi(${\pi}$)-shaped RC rahmen bridge is analyzed and designed by using strut-tie model. Adequacy for the application of strut-tie model is verified by comparison with the way used in current design practice. As a result that designing the structures should be maked a comparison between strut-tie model and current conventional design method.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.26-27
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• 2006

Capping mechanisms during the compaction of pharmaceutical powders were explored. Both experimental and numerical investigations were performed. For the experimental study, an X-ray Computed Microtomography system has also used to examine the internal failure patterns of the tablets produced using a compaction simulator. Finite element (FE) methods have also been used to analyse the powder compaction. The experimental and numerical studies have shown that the shear bands developed at the early stage of unloading appear to be responsible for the occurrence of capping. It has also been found that the capping patterns depend on the compact shape.

• Structural Engineering and Mechanics
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• v.51 no.4
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• pp.565-579
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• 2014

The pullout capacity of plate anchors has been studied extensively over the past 40 years. However, very few studies have attempted to calculate the pullout capacity of anchors in sandy slopes. In this paper, three upper bound approaches are used to study the effect of a sloping ground surface and friction angle on pullout capacity and failure of plate anchors. This includes the use of; simple upper bound mechanisms; the block set mechanism approach; and finite element upper bound limit analysis. The aim of this research is to better understand the various failure mechanisms and to develop a simple methodology for estimating the pullout capacity of anchors in sandy slopes.