• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.469-474
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• 1999

The object of study is analysis to joint crack behavior of cracked joint concrete pavement. In the new constructing concrete pavement, joint crack behavior was compared general joint depth D/4 with joint depth D/3 and D/5 that it's environmental effects changed temperature and humidity. After joint saw cutting joint section was predicted crack at joint depth D/5 test section from the result for monitoring development of crack. In the setting of data logger system of the joint section, it's data compared see with the naked eye. In the research, development of crack at the joint section should effect to joint saw timing latter than joint depth. This performance could be the minimum of deterioration to the early curing. In this research, At new constructing of joint concrete pavement of highway, the monitoring system be setting after finished paving and joint sawing. The system and see with the naked eye could be analysis to pavement behaviors from collecting data at the test section. This system could be monitoring shot term and long term. In this report, joint section of crack behavior analysis used to collected data during a month after paving and joint sawing.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2001.05a
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• pp.168-171
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• 2001

Due to intrinsic load eccentricity, severe peel stress concentration occurs at both ends of the single-lap joint. To avoid load eccentricity as well as the singular tensile peel stress in the joint interface, composite wavy-lap joint is proposed. In this paper, refined 3-D stress analysis of wavy-lap joint is performed by finite element method using parallel mutifrontal solver. Analysis results show that the singular tensile peel stress concentration is totally avoided in wavy-lap joint, and that loads are more evenly transferred over the length of the joint. Therefore, the strength of wavy-lap joint is significantly higher than that of conventional single-lap joint. And it is believed that even higher strengths can be obtained by optimizing the new design configuration.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.1
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• pp.53-67
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• 1996

The dynamic characteristics of mechanical structure are strongly affected by the properties of joint parameters. In this study, the test structures are constructed with two beams which are clamped by bolts, and a bolted joint which is modelled as a lumped stiffness element. To idientify the dynamic joint parameters with variance of clamping torque of bolts, the sensitivity analysis and the mode energy analysis methods are investigated experimentally. As a reult of these two methods, stiffnesses of bolted joint are experimentally found to increase as the clamping torque increases. These stiffnesses identified from the sensitivity analysis and the mode energy analysis method have some difference.

• Tunnel and Underground Space
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• v.4 no.1
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• pp.1-16
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• 1994

The study on the flow characteristics and analysis of groundwater in discontinuous rock mass is very important, since the water inflow into the underground opening during excavation induces serious stability and environmental problems. To investigate the flow through single rock joint, the effect of various aperture distribution on the groundwater flow has been analyzed. Observed through the analysis is the "channel flow", the phenomenon that the flow is dominant along the path of large aperture for given joint. The equivalent hydraulic conductivity is estimated and verified through the application of the joint network analysis for 100 joint maps generated statistically. Both the analytic aproach based on isotropic continuum premise and the joint network analysis are tested and compared analyzing the gorundwater inflow for underground openings of different sizes and varying joint density. The joint network analysis is considered better to reflect the geometric properties of joint distribution in analyzing the groundwater flow.ater flow.

• Explosives and Blasting
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• v.35 no.4
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• pp.1-9
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• 2017

This study undertakes an evaluation of blast effect through the analysis of the contribution rate and effect that different artificial joint number, artificial joint spacing and artificial joint angle have on blast velocity. Blast velocity according to the different state of the artificial joint was obtained using AUTODYN, a dynamic analysis program. The result of the numerical analysis was subjected to further normalization analysis. For the contribution rate of design factors was analyzed using the robust design method. The orthogonal array used in the analysis was $L_9(3^4)$ and each parameters were having 3 levels. The result of normalization analysis regarding the artificial joint angle was indicated a tendency in which blast velocity decreased. The result of analyzing blast velocity regarding artificial joint spacing and artificial joint angle was indicated a tendency in which blast velocity decreased as artificial joint spacing increased when the angle was perpendicular. In the case of blast velocity contribution rates they were ranked in the descending order of artificial joint angle, artificial joint number, artificial joint spacing.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1561-1564
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• 2003

In the dynamic analysis model of full vehicles, the ball joint is usually modeled as an ideal joint. Searching a ball joint, the engineering plastic covers metal and the plastic has little compliance. It is expected that the compliance will physically have an influence on load transfer. This thesis presents a dynamic model considering the compliance of a ball joint, and studies an influence related to load transfer. It models the compliance of a ball joint to 3 directional spring. Likewise, it researches the load of a ball joint via a four-post simulation of a full vehicle, comparing with a model considered compliant and the model of an ideal joint. As a result, the difference between the compliance and the ideal joint model was determined. For this reasons, to conduct precision load prediction for durability analysis, dynamic analysis considering the compliance of bali joint should be required.

• Journal of the Korean Wood Science and Technology
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• v.23 no.3
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• pp.8-15
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• 1995

This analytical study was carried out to make quality and productivity up in designing the frame-type furniture with semi-rigid joint by understanding the mechanical and structural behavior of the joint and by evaluating the validity of application of the time-saving Finite Element Method to its structural analysis. Slope deflection equation for rigid joint was modified to describe the moment-rotation behavior of semi-rigid joint and the joint stiffness factor(Z) could be calculated to lessen the experimental expense. It was proved that Finite Element Analysis with imaginary elements having equivalent MOE to the semi-rigid joint could be the alternative method for the structural analysis of the frame-type furniture, comparing the internal rotation of the 2-dimensional beam-to-column model with two-pin(wooden dowel) from the finite element method with other available theoretical and experimental rotation value.

• Journal of KSNVE
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• v.9 no.5
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• pp.975-983
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• 1999

This paper describes the dynamic characteristics of the joint structures in case of using the simplified beam model in the F. E. analysis. The modeling errors, when replace the shell with the beam, are investigated through F. E. normal modes analysis. Normal mode analysis were performed to obtain the natural frequencies of the L and T shaped joints with various type of channels. The results were analyzed to access the effects of the models on the accuracy of F.E. analysis by identifying the geometric factors which cause the error. The geometric factors considered are joint angle, channel length, thickness and area ratio of the hollow section to the filled one. The joint stiffness evaluation technique is developed in this study using normal modes analysis with Lumped Mass. With this method, the progressively improved results of F. E. analysis are obtained using the simplified beam model. The static and normal modes analysis are performed with the joint stiffness values obtained by the Kazunori Shimonkakis' virtual stiffness method and the proposed method and these simplified modeling errors are compared.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2007.04a
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• pp.757-762
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• 2007

The lining segment which is the main structure of the shield tunnel consists of joints, not continua. Past international and domestic design data have been commonly used for design practices without specific verification about the structural analysis model, design load, and affection of the soil constant of the lining segment. In this study, the propriety is estimated through the comparison between analytical solution and numerical solution for segment analysis and design models of the shield tunnel which is being used internationally and domestically. As a result, the full. circumferential beam jointed spring model (1R-S0) is suggested by considering aspects of convenient use, application to field condition, and accuracy of analysis result. With suggested model, the parameter analysis was conducted for joint stiffness, ground rigidity, joint distribution, and joint number.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.4
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• pp.148-153
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• 2008

Although manual traction, one of pain therapies, was applied in clinic to relief pain, the study was rare on the manual force and displacement of ligaments at knee joint during manual traction. The aim of this study is to quantify not only manual force at knee joint but also elongated displacement of joint ligament by C-arm scanning and motion analysis. Twenty-one healthy subjects were tested with manual traction from grade I to grade III under neutral position by a physical therapist. We calculated traction force using joint farces of both hands and elongated displacement of joint ligament were measured. The results showed that traction forces by C-arm scanning analysis were averagely 1.67-fold greater than those by motion analysis, but elongated displacements were instead averagely 2.36-fold smaller than motion analysis. Finally, we could estimate relationship between traction force and elongated displacement at knee joint by two methods.