• Journal of Korean Association for Spatial Structures
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• v.13 no.2
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• pp.83-91
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• 2013

The core aim of this dissertation is to empirically scrutinize a strength characteristic of beam-column frame subjected to the cyclic lateral load, a beam-column frame of un-reinforced masonry wall, and a shear wall frame. First and foremost, I embark upon making three prototypes vis-$\grave{a}$-vis this research. By conducting this process, I touch on an analysis of cyclic behavior and a damage characteristic of the beam-column frame, the beam-column frame of un-reinforced masonry wall, and the shear wall frame. What is more, through the previous procedure, the next part delves into the exact stress transfer path and the destructive mechanism to examine how much and how strong the beam-column frame of un-reinforced Masonry Wall does have a resistance capacity against earthquake in all the architecture constructed by the above-mentioned frame, as well as school buildings. In addition to the three prototypes, two more experimental models, a beam-column frame and shear wall frame, are used to compare with the beam-column frame of un-reinforced masonry wall. Lastly, the dissertation will suggest some solutions to improve the resistance capacity against earthquake regarding all constructions built with non bearing wall following having examining precisely all the analysis with regard to not only behavior properties and the damage mechanism of the beam-column frame and the beam-column frame of un-reinforced Masonry Wall but also the resistance capacity against earthquake of non bearing wall and school buildings.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2005.04a
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• pp.644-651
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• 2005

The purpose of this paper is to compare the control effect of toggle brace system having amplifying displacement mechanism with that of conventional brace system when the identical MR damper is applied to each system. The force-displacement and lone-velocity relationships of MR damper are obtained using harmonic load test and the analytical model for MR damper is presented. White noise excitation tests of a single degree of freedom system with MR-toggle brace system and MR-chevron system are conducted and the transfer functions of the systems are compared. Test results show that the control effect of the toggle system is superior to that of the conventional brace system.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.272-275
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• 2004

This study is to propose a modified equivalent frame method under lateral loading. ACI 318-02 allows the equivalent frame method to conduct slab analysis subjected to lateral loads. However, current method can not predict the behavior of the slabs particularly under lateral loading because the equivalent frame method in the ACI 318 has been developed against gravity loads. This study provides more precise model for the analysis of the flat plate slabs under lateral loading. The model reflect the force transfer mechanism of slabs, column and torsional member more accurately than the existing model. The accuracy of this model is verified by compared with finite element method analysis results.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.185-188
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• 2005

Bond between reinforcing bar and surrounding concrete is supposed to transfer load safely in the process of design of reinforced concrete structures. Bond strength of ribbed reinforcing bars tends to split concrete cover, by wedging action, or shear the concrete in front of the ribs. In this study, using a reducing bearing angle theory, bond strengths of beam end specimen are predicted. Values of bond strength obtained using the analytical model are in good agreement with the bond test results. The analytical model provides insight into bond mechanism and the effects of bearing angle on the bond strength of deformed bars to concrete.

• Fibers and Polymers
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• v.5 no.3
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• pp.177-181
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• 2004

Current efforts to establish links between geometrical features and mechanical performance of nonwoven fabrics in general, and of point-bonded (spot-bonded) nonwovens in particular has been made using the measurements of Fiber Orientation Distribution Function (ODF) and tensile modulus which occurs during controlled-deformation experiments. Image analysis technique (using the Fast Fourier Transform) was used to quantify the fiber orientation distribution. The results suggest that, within a typical window of processing conditions, the fiber orientation has a significant influence on the anisotropical behavior of nonwoven. The data also suggest that mechanical anisotropy of thermally point-bonded nonwovens is likely to be governed by different load transfer mechanism according to the applied macroscopic tensile direction.

• Computers and Concrete
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• v.7 no.5
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• pp.437-453
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• 2010

CFRP has been widely used for strengthening reinforced concrete members in last decade. The strain transfer mechanism from concrete face to CFRP is a key factor for rigidity, ductility, energy dissipation and failure modes of concrete members. For these reasons, determination of the effective CFRP bonding length is the most crucial step to achieve effective and economical strengthening. In this paper, generalizations are made on effective bonding length by increasing the amount of test data. For this purpose, ANSYS software is employed, and an experimentally verified nonlinear finite element model is prepared. Special contact elements are utilized along the concrete-CFRP strip interface for investigating stress distribution, load-displacement behavior, and effective bonding length. Then results are compared with the experimental results. The finite element model found consistent results with the experimental findings.

• Journal of the Korean Wood Science and Technology
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• v.44 no.4
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• pp.505-514
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• 2016

To study mechanical properties of fiberglass reinforced wood-based composite (FRWC), fiberglass with a diameter of $20{\mu}m$ was selected to prepare test specimens. Mechanical properties of fiberglass reinforced wood-based composite were determined by three-point-bending test while its microstructure was characterizes by scanning electron microscopy (SEM). The results showed that mechanical properties of fiberglass reinforced wood-based composite were superior to that of the wood fiberboard based on the contrasting mechanical curves and the analysis of fracture mechanism. It is believed that the material design with this "sandwich" structure brings a unique buffering capacity of fiberglass into play in the composites. So the specimen did not produce a sudden fracture failure at high level of applied loads because it had a bearing ability. The SEM analysis showed that the working strength of PVAc adhesive was high; under a bearing force, it could properly transfer a load. In addition, glass fiber mesh and wood fiber board combined well.

• Korean Journal of Weed Science
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• v.17 no.4
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• pp.345-361
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• 1997

Photoassimilates translocate from regions of carbohydrate synthensis(source) to regions of carbohydrate utilization or storage(sink). In the source, assimilate loads into the phloem for long-distance transport. Current evidence suggests that there are twig loading mechanisms : one involves assimilate transfer via the apoplasm and then load into the phloem by carrier-mediated proton-sucrose cotransport, while the other involves movement through the continuous symplastic connections between the mesophyll cells and the phloem. Inspite of problems associated with the interpretation of experiments, the evidence for apoplastic loading remains convincing because the apoplastic loading systems explains well the observed accumulation capacity arid the selectivity of assimilate uptake by tile phloem.

• Steel and Composite Structures
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• v.47 no.2
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• pp.203-216
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• 2023

The composite beam connections often encountered fracture failure in the welded bottom flange joint, and a bottom flange bolted connection has been proposed to increase the deformation ability of the bottom flange joint. The seismic performance of the bottom flange bolted composite beam connection was suffered from both the composite action of concrete slab and the asymmetric load transfer mechanisms between top and bottom beam flange joints. Thus, this paper presents a comprehensive numerical study on the working mechanism of the bottom flange bolted composite beam connections. Three available modelling methods and a new modelling method on the flange-stud-slab interactions were compared. The efficient numerical modeling method was selected and then applied to the parametric study. The influence of the composite slab, the bottom flange bolts, the shear composite ratio and the web hole shape on the seismic performance of the bottom flange bolted composite beam connections were investigated. A hogging strength calculation method was then proposed based on numerical results.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.197-200
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• 2008

The RC corbels with the ratio of shear span-to-effective depth less than 1 are commonly used to transfer loads from beams to columns. The ultimate strengths and structural behaviors of RC corbels are controlled by the shear span-to-effective depth ratio, strength of concrete, shape and quantity of the reinforcement, and geometry of corbels. In this study, a simple indeterminate strut-tie model reflecting all characteristics of the ultimate strengths and complicated structural behaviors is presented for the design of RC corbels. In addition, a load distribution ratio, defined as a magnitude of load transferred by a horizontal truss mechanism, is proposed to help structural designers perform the design of RC corbels by using the strut-tie model approaches of current design codes. The ultimate strengths of 30 RC corbels tested to failure are evaluated by using the ACI 318-05's strut-tie model code for the validity check of the proposed indeterminate strut-tie model and load distribution ratio.