• Structural Engineering and Mechanics
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• v.21 no.4
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• pp.393-406
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• 2005

Cyclic loading tests were carried out on six half-scale reinforced concrete beam-column subassemblages designed to the current Chinese Seismic Design Code for Buildings. The deformation behavior and restoring force characteristics of the subassemblages were studied. Emphasis was directed on their seismic behavior and deformation components. Based on test data and a simplified analysis model of the global and local deformation, the contribution of the deformation components due to beam flexure, column flexure, joint shear, and slippage of longitudinal reinforcement in the joint to the global deformation of subassemblages at different displacement amplitudes of cyclic loading was investigated.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.1085-1087
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• 2002

Deformation of soft tissue is known inhomogeneous and non-linear in general. In this study, we propose a measurement methodology of local/global strain during soft tissue elongation precisely using laser extensometer which has high accuracy, resolution and is possible to measure global/local strain. The mechanical tensile test are performed on tibialis cranialis, flexor hallucis longus, extensor digitorum longus of swine hindlimb. In order to measure target displacement, reflective marker is attached to detect elongation on specimen using surgical adhesive. The result of this study is to show that laser extensometer is valid to measure longitudinal elongation which is inhomogeneous and non-linear fur soft tissue.

• Journal of the Korean GEO-environmental Society
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• v.14 no.9
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• pp.39-47
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• 2013

Local deformations in back filling materials of two sands and one glass bead with different particle shapes behind a rigid retaining wall were studied. Two kinds of boundary conditions were compared: active wall translation and active rotation of the wall about its toe. Effect of the speed of active wall translation was also investigated. The digital image correlation method was used to analyze local deformation developments inside the materials. Test results showed that particle shape and density mainly influence the inclination angle and width of the shear band. The general shear band pattern is strongly dependent on the wall movement mode, while it was little influenced by particle shape. Within a limited range of wall speed in this study, shear band became wider and local deformation became larger with increase of wall speed.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.49 no.8
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• pp.617-626
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• 2021

During supersonic flight of vehicles, the thermal behavior of structures under high-temperature environment is important for thermal-structural design. In this study, full-field thermal deformation and stress concentration of the notched structure was performed using global-local multi-digital image correlation (multi-DIC) systems. This techniques were developed and implemented by multi-DIC systems consists of 2D DIC system and 3D DIC system. The specimen was heated in a heating chamber to achieve the thermal expansion behavior. Then the images of structure's deformation and stress concentration at various temperature were recorded and analyzed by multi-DIC system. Afterward, full-field thermal deformation of the notched structure was determined with DIC technique and stress concentration at the notched structure was calculated by further processing. Finite element analysis of the notched structure is performed in ABAQUS^TM and the results of the experiments show good agreement with those obtained from simulation. The results achieved in this study show the efficiency of the muilti-DIC method in thermal deformation as well as stress concentration of notched structure.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.60-65
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• 2007

Local buckling behaviors of aluminum square tube beams reinforced by aluminum plates under three point bending loads have been analyzed using experimental tests combined with theoretical and finite element analyses. For this analysis true stresses were determined from applied loads and cross-sectional area records of a tensile specimen with a rectangular cross-section by real-time photographing. True strains were also obtained from in-situ local elongation measurements of the specimen gage portion by the multi-point scanning laser extensometer. Six kinds of aluminum tube beam specimens reinforced by aluminum plates were employed for the bending test. The bending deformation behaviors up to the maximum load analyzed by the numerical simulation agreed well with experimental ones. After passing the maximum load, reinforcing plate hindering the local buckling of the tube beam was debonded from the aluminum tube beam. An aluminum tube beam strengthened by aluminum plate on the upper web showed the most excellent bending capacity, which could be explained on the basis of the neutral axis shift and the local buckling deformation range.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.22-33
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• 2008

The plane strain test has been used widely in order to examine the stress-strain relation and failure behavior. Its advantages are more realistic simulation of deformation and failure behaviors of soils. Most plane strain tests have been carried out with restrained end plates due to difficulties in manufacturing the equipment with free end condition and also performing it. In this study, plane strain tests with/without bottom plate restraint were performed on Jumunjin-sand. The measurement of overall and local deformation was accomplished by digital image correlation technique as well as external LVDT. By applying digital image correlation method using two consecutive images captured through the transparent wall, local deformation behavior of various parts inside the specimen was estimated. From digital image analysis result, the restrained effect of end plate was examined about formation and development of shear band, and deformation mechanism of sand under plane strain condition.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.30 no.2
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• pp.111-117
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• 2017

In this paper, a local deformation effect in thin-walled box beams is investigated via a finite element modal analysis. The analysis is carried out for single-cell and multi-cell box beam configurations. The single-cell box beam with and without a neck, which mimics a simple wind-turbine blade, is analyzed first. The results obtained by shell elements are compared to those of one-dimensional(1D) beam elements. It is observed that the wall thickness plays a crucial role in the natural frequencies of the beam. The 1D beam analysis deviates from the shell analysis when the wall thickness is either thin or thick. The shell modes(local deformations) are dominant as it becomes thin, whereas the shear deformation effects are significant as it does thick. The analysis is extended to the single-cell box beam with a neck, in which the shell modes are confined to near the neck. Finally the multi-cell box beam with a taper, which is quite similar to real wind-turbine blade configuration, is considered to investigate the local deformation effect. The results reveal that the 1D beam analysis cannot match with the shell analysis due to the local deformation, especially for the lagwise frequencies. There are approximately 5~7% errors even if the number of segments is increased.

• Tribology and Lubricants
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• v.14 no.3
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• pp.59-64
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• 1998

This paper presents the deformation characteristics of cam ring in a balanced type vane pump. Cam ring is operated in the high-pressure condition. Therefore the local deformation of cam ring affects the characteristics of compression, vane motion and noise and vibration. We analyzed the deformation of cam ring for the three types by using the finite element method. The deformed shape of cam ring and the effects of deformation on the compression are presented. As a result of analysis, we know that the right hole of the cam ring has advantage for reducing the pressure overshoot.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2004.10a
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• pp.61-64
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• 2004

The strength characteristics as well as deformation behaviors of honeycomb sandwich composite (HSC) structures were investigated under bending in consideration of various failure modes such as skin layer yielding, interface-delamination, core shear deformation and local buckling. Deformation behaviors of honeycomb sandwich plates were observed with various types of aluminum honeycomb core and skin layer. Their finite-element analysis simulation with a real model of honeycomb core was performed to analyze stresses and deformation behaviors of honeycomb sandwich plates. Its results were very comparable to the experimental ones. Consequently, the increase in skin layer thickness and in cell size of honeycomb core had dominant effects on the strength and deformation behaviors of honeycomb sandwich composites.

• Structural Engineering and Mechanics
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• v.51 no.6
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• pp.893-907
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• 2014

Meshless local collocation method produces much better conditioned matrices than meshless global collocation methods. In this paper, the meshless local collocation method based on thin plate spline radial basis function and first-order shear deformation theory are used to calculate the natural frequencies and mode shapes of laminated composite shells. Through numerical experiments, the accuracy and efficiency of present method are demonstrated.