• Journal of Institute of Control, Robotics and Systems
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• v.19 no.4
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• pp.357-363
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• 2013

Most serious patients who have the paralysis of their ankles can't use of their feet freely. But their ankles can be recovered by an ankle bending rehabilitation exercise and a ankle rotating rehabilitation exercise. Recently, the professional rehabilitation therapeutists are much less than stroke patients in number. Therefore, the ankle-rehabilitation robot should be developed. The developed robot can be dangerous because it can't measure the applied bending force and twisting moment of the patients' ankles. In this paper, the six-axis force/moment sensor for the ankle-rehabilitation robot was specially designed the weight of foot and the applied force to foot in rehabilitation exercise. As a test results, the interference error of the six-axis force/moment sensor was less than 2.51%. It is thought that the sensor can be used to measure the bending force and twisting moment of the patients' ankles in rehabilitation exercise.

• Structural Engineering and Mechanics
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• v.52 no.4
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• pp.843-855
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• 2014

Concrete infill and reinforcement are one of the most well-known strengthening methods of structural elements. This study investigated flexural performance of concrete infill composite PHC pile (ICP pile) reinforced by infill concrete and longitudinal rebars in hollow PHC pile. A total four series of pile specimens were tested by four points bending method under simply supported conditions and investigated bending moment experimentally and analytically. From the test results, it was found that although reinforcement of infilled concrete on the pure bending moment of PHC pile was negligible, reinforcement of PHC pile using infilled concrete and longitudinal rebars increase the maximum bending moment with range from 1.95 to 2.31 times than that of conventional PHC pile. The error of bending moment between experimental results and predicted results by nonlinear sectional analysis on the basis of the conventional layered sectional approach was in the range of -2.54 % to 2.80 %. The axial compression and moment interaction analysis for ICP piles shows more significant strengthening effects of infilled concrete and longitudinal rebars.

• Journal of the Korean Geotechnical Society
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• v.23 no.10
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• pp.85-96
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• 2007

The application of soil nailing method has increased because it provides easier construction, economic efficiency, and stability than existing support methods. The mechanical comprehension of the soil-nailing system has not been established and the resisting shear force and bending moment of the soil-nail have been disregarded for the design of soil-nailing system. The soil nail consists of cement associated with rebar and resists shear force and bending moment mobilized by applied loading or soil-self weight. In this study, the slope analysis in the consideration of the resisting shear force and bending moment of the nail has been performed using $FLAC^{2D}$, which is programed by the finite difference method.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.885-890
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• 2001

For the shear strength prediction of reinforced concrete beams, this paper considered the bending moment effect. Experimental results of the thirty-seven reinforced concrete beams were compared with analytical results by the FA-STM, TATM and TATM considered bending moment effect. While Ratios of test results to analytical results by using the truss models does not considered the bending moment effect decreased as shear span ratio increased, those by using the proposed method considered that were almost constant regardless of the increase of the shear span ratio. Predicted results obtained from proposed method agreed well with the experimental results.

• Structural Engineering and Mechanics
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• v.27 no.6
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• pp.639-650
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• 2007

Applying the method calculating creep of Concrete Filled steel Tube (CFT) members based on the Elastic Continuation and Plastic Flow theory for concrete creep with the finite element method, the paper develops a new numerical method for the creep of CFT arch bridges considering effects of bending moment. It is shown that the method is feasible and reasonable through comparing the predicted stresses and deflection caused by the creep with the results obtained by the method of Gu et al. (2001) based on ACI209R model and experimental data of an actual CFT arch bridge. Furthermore, nine CFT arch bridges with different types are calculated and analyzed with and without the effects of bending moment. As a result, the bending moment has considerable influences on long-term deformations and internal forces of CFT arch bridges, especially when the section of arch rib is subjected to a large bending moment.

• Elastomers and Composites
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• v.41 no.2
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• pp.125-130
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• 2006

To understand the effect of midsole on the bending stiffness of footwear, bending moment is studied with various hardness and thickness of polyurethane(PU) and poly(ethyl one-co-vinylacetate)(EVA) foams which composed in footwear midsole. The initial bending moment of footwear was appeared at $19^{\circ}$ on bending angle of footwear, and this bending angle was not depend on thickness and hardness of midsole. The bending moments of footwear were also increased with increase of the hardness and thickness of misole which were composed in footwear. Increased hardness and increased thickness of foam and midsole also cause a greater bending moment of the sports shoe, respectively.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.754-757
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• 2004

This study was performed to propose design bending moment formula for long-span slab on a composite two-girder bridge. FEM models representing slab spaning between 4m and 12m were analyzed, and parameters such as girder flexibility and orthotropy of slab were considered. By regression of the parametric analyses results, the moment formula that can predict the design moment with reasonable margin of safety and correctness was developed. The research also showed that the design bending moment from Korean Bridge Design Code overestimated the design moment for the span length under gm, and underestimated for the span length over 9m.

• Journal of the Korean Society of Safety
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• v.20 no.2 s.70
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• pp.18-25
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• 2005

This study performed finite element analysis on the pipe bend with various bend angles under loading conditions of internal pressure and combined pressure and bending, to investigate the effect of bend angle on the collapse behavior of pipe bend and on the stress state in the bend region. In the analysis, the pipe bends with bend angle of $5\~90^{\circ}$ were considered, and the bending moment was applied as in-plane closing and opening modes. From the results of analysis, it was found that the collapse moment of pipe bend increases with decreasing bend angle. As the bend angle decreases, also, the equivalent stress at intrados region increases regardless of bending mode. Under closing mode bending especially, the increase in stress at intrados is significant so that the maximum stress region moves from crown to intrados with decreasing bend angle.

• Journal of Construction Engineering and Project Management
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• v.3 no.4
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• pp.12-19
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• 2013

Green Frame is an environmentally friendly column-beam system composed of composite PC members that can increase buildings' life spans while reducing resource consumption. Typically, connections of PC and RC columns occur at the boundaries of each floor, which is at the upper section of slabs, causing the boundary of each floor to generate the maximum moment. Although it is not optimal in terms of structural safety to connect members at a location where the moment is high, this approach is highly adopted due to its constructability. We propose that a superior approach that employs the concept of connecting columns at the low bending moment zone can be applied to quickly and safely install green columns, the main structural members of Green Frame. Connection of green columns at the low bending moment zone can be classified into three techniques, depending on the method of reinforcing the joints, which have different connection characteristics and construction methods. Research is needed to compare the features of each method of reinforcing the joints so that the most appropriate column connection method can be chosen for the site conditions. This study aims to confirm the structural safety of the connection component at the low bending moment zone and to compare and analyze the construction duration, unit price, quality and safety performance of each column connection method. The study results are anticipated to activate the use of composite precast concrete and to be used as development data in the future.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.9
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• pp.110-121
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• 2001

During hot pipe bending using induction heating, the wall of bending outside is thinned by tensile stress. In design requirement, the reduction of wall thickness is not allowed to exceed 12.5%. So in this study, two methods of bending, one is loading of reverse moment and the other is loading of temperature gradient, have been investigated to design pipe bending process that satisfy design requirements. For this purpose, finite element analysis with a bending radius 2Do(outer diameter of pipe) has been performed to calculate proper reverse moment and temperature gradient to be applied. Induction heating process has been analyzed to estimate influence of heating process parameters on heating characteristic by finite difference method. Then pipe bending experiments have been performed for verification of finite element and finite difference analysis results. Experimental results are in good agreement with the results of simulations.