• Journal of the Korea Furniture Society
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• v.19 no.5
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• pp.350-357
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• 2008

This research investigates the bending properties to predict the work-energy to maximum load and impact bending energy from static bending and impact bending test. Specimens were prepared from lumber made of thinning crop-trees. Matched specimens were used for MC 12% and green moisture specimens to measure the effect of moisture content on the absorbed energy from static and impact bending tests. The bending properties such as MOE, MOR, etc. is a good predictor to investigate the work-energy and work-energy per unit volume from static bending and impact bending test. The impact bending energy is increased with increasing moisture content. However, the work to maximum load from static bending test is increasing with increasing the MC only for higher density species.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.8 s.251
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• pp.1008-1015
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• 2006

Based on three-dimensional (3-D) FE limit analyses, this paper provides plastic limit, collapse and instability load solutions for pipe bends under combined pressure and in-plane bending. The plastic limit loads are determined from FE limit analyses based on elastic-perfectly plastic materials using the small geometry change option, and the FE limit analyses using the large geometry change option provide plastic collapse loads (using the twice-elastic-slope method) and instability loads. For the bending mode, both closing bending and opening bending are considered, and a wide range of parameters related to the bend geometry is considered. Based on the FE results, closed-form approximations of plastic limit and collapse load solutions for pipe bends under combined pressure and bending are proposed.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.841-844
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• 1997

Sandwich structure is widely used in various fields of industry due to its excellent strength and stiffness compared with weight. We studied the buckling and bending behavior with respect to the variation of design parameters such as length, height, and thickness of honeycomb sandwich core. We found that as the density and the thickness of core become higher, the value of critical bucking load increased significantly. We found that the effect of bending stress due to critical buckling load resulted in high bending stress and the value of bending stress decreased in half according to the increase of length of core. The effect by bending stress is dominant above the portion of the intersection line between bending stress and the effect of buckling is dominant below the potion of it. We could get proper thickness ratio and density of core according to applied load conditions.

• Journal of Welding and Joining
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• v.24 no.3
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• pp.55-59
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• 2006

This paper is concerned with a study on cyclic bending load of bus folding door pillar including adhesive bonding and spot welding. Three specimen types were used such as spot welding, I-type adhesive bonding and M-type adhesive bonding in this study. The tensile-shear tests were carried out to evaluate the tensile-shear strength of these three specimen types. Also four-point bending tests were carried out to evaluate the static and dynamic bending load. From the results, using adhesive bonding has a better effect on the static and dynamic bending load than using spot welding. Therefore, manufacturing better structural products can be expected by applying hybrid welding using adhesive and spot welding to those.

• Journal of Welding and Joining
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• v.33 no.2
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• pp.62-68
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• 2015

This study investigates the appropriate range of reverse bending load for the CTOD test of thick weld by observing improvement of pre-crack shape and determination of the limit applicable load. In order to do it, the effect of the amount of the reverse bending load on the maximum deviation of the pre-crack length was investigated by the extensive tests, and the variation of plastic zone size in way of the crack tip under reverse bending load were evaluated by FEA. With the results obtained by the experiments and FEA, the proper range of reverse bending load was suggested. The effectiveness of the reverse bending method was verified by examining the pre-crack straightness after CTOD tests of thick weld specimens with various thickness and strength.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.12
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• pp.2011-2018
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• 2003

To analyze the bending collapse behavior of an aluminum square tube beam under a bending load, a finite element simulation for the four-point bending test has been performed. Using an aluminum tube beam specimen partly inserted with two steel bars, the local buckling deformation near the center of the tube beam was induced. The maximum bending load and the bending collapse behavior obtained from the numerical simulation were in good agreement with experimental results. Using a combination of the four-point bending test and its finite element simulation, analysis of the local buckling and the accompanied bending collapse behavior of aluminum tube beam could be quantitative accomplished.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.43 no.5
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• pp.567-576
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• 2023

In general, RC beam members are designed as flexural members, considering only the bending load. However, in actual buildings, axial and bending load are simultaneously applied due to the continuity between members. As a result, the bending strength of the RC beam member increases, but the displacement decreases, and cracks are mainly concentrated in the center of the beam. Therefore, in this study, the bending performance of both normal and strengthened RC beam using carbon fiber sheets subjected to combined axial and bending load was experimentally evaluated. The carbon fiber sheets were wrapped around the middle of the specimens, and axial and bending load were applied simultaneously to the beams. The magnitude of the axial force and the effects of carbon fiber sheet reinforcement on the deformed shape, bending strength, deflection, and ductility of the RC beams were analyzed. The results show that as the applied axial force increased, the maximum bending strength increased, but the ductility decreased 64%. The bending strength of the strengthened beams increased up to 27%, the maximum deflection decreased around 8% and the ductility increased by up to 43%.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.2 s.95
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• pp.82-86
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• 1999

An experimental study has been carried out to reduce bending load, surface roughness and springback in bending process of stainless steel sheets. A U-bending test has been performed to investigate appropriate process parameters for getting better surfaces and accurate dimensions of stainless steel products. In the test, selected process parameters are die material, lubricant, and die clearance. Die materials used in the test are STD11(HRC60), STD11(TiCN), and AMPCO. From the test results, we can suggest that AMPCO dies are most suitable for reducing bending load and surface roughness of stainless steel sheets. And STD11 dies are favorable for avoiding spring-back in the stainless steel sheet-bending.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.10
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• pp.4629-4635
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• 2012

This study was aimed at the relationship between peak EMG amplitude on low back muscles acting on L5/S1 and load center of gravity, trunk lateral bending while lifting an object. Musculoskeletal disorders including low back pain can occur even when handling heavy objects only once as well as when doing non-heavy materials repeatedly. 11 male subjects with average 23 age were required to lift a 15.8kg object symmetrically three times. Peak EMG amplitudes on 6 muscles related with L5/S1 were recorded and analyzed. The lifting conditions consisted of lifting symmetric load with no trunk lateral bending, asymmetric load with no trunk lateral bending, and asymmetric load with trunk lateral bending to the load center of gravity within an object. The results showed that peak EMG amplitude on back muscles contralateral to load center of gravity was observed greater in comparison with the symmetric load. Also, in case of lifting asymmetric load the posture with trunk lateral bending increased peak EMG amplitude on muscles contralateral to load center of gravity more than with no trunk lateral bending. This research can be used as one administrative intervention in order to reduce the low back pain incidence with suggesting workers that they keep the trunk not bending to load center of gravity if possible when lifting a heavy asymmetric object.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.209-214
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• 2001

Most reinforce concrete Columns of Building structure are subjected to both axial load and biaxial bending. However, It is hard to estimate the moment capacity of biaxial bending by exact solution. Thus, columns under biaxial bending are designed by approximate methods in practice. The purpose of this study is to compare experimental result with approximate methods and exact solution by computer. Parameters of the present test are compressive strength of concrete (350, 585, 650kgf/$\textrm{cm}^2$) and shape ratio of rectangular section. Ultimately, an experimental shape factor for rectangular RC column section is obtained through the test program. The shape of load contour is dominated by this shape factor obtained experimentally. So, reasonable design of RC columns subjected to both axial compression and biaxial bending depends on load contour.