• Proceedings of the Korean Geotechical Society Conference
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• 2001.06a
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• pp.1-11
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• 2001

This Paper presents the result of a parametric study on the behavior of stiffened grid reinforced segmental wall resting on non-yielding foundation. The parametric study was conducted using the nonlinear finite element analysis. In the finite element analysis, the step by step construction of the wall such as backfill, block reinforcement, block/backfill and soil/reinforcement interfaces were carefully modeled. The mechanical behavior of stiffened grid reinforced segmental walls was then investigated based on the result of analysis with emphasis on the effect of reinforcement stiffness on the behavior of the wall. The results of analysis indicate that the horizontal wall displacement decrease; with increasing the reinforcement stiffness at a decreasing rate, and that the horizontal stress at the back of the reinforced soil block does not much vary with the reinforcement stiffness. It is also revealed that the calculated maximum vertical stress at the base of the reinforced soil block agrees well with that based on the Meyerhof distribution and that the reinforcement and the connection force are considerably smaller than what might be expected based on the current design assumptions. The implications of the findings from this study to current design approaches were discussed in detail.

• Geomechanics and Engineering
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• v.8 no.4
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• pp.595-613
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• 2015

An experimental investigation into the uplift capacity of horizontal square plate anchors in sand with and without geogrid reinforcement is reported. The parameters investigated are the effect of the depth of the single layer of geogrid, vertical spacing of geogrid layers, number of geogrid layers, length of geogrid layers, the effects of embedment depth, and relative density of sand. A series of three dimensional finite element analyses model was established and confirmed to be effective in capturing the behaviour of plate anchor-reinforced sand by comparing its predictions with experimental results. The results showed that the geogrid reinforcement had a considerable effect on the uplift capacity of horizontal square plate anchors in sand. The improvement in uplift capacity was found to be strongly dependent on the embedment depth and relative density of sand. A satisfactory agreement between the experimental and numerical results on general trend of behaviour and optimum geometry of reinforcement placement is observed. Based on the model test results and the finite element analyses, optimum values of the geogrid parameters for maximum reinforcing effect are discussed and suggested.

• Proceedings of the Korean Geotechical Society Conference
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• 2001.10b
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• pp.60-76
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• 2001

The grout-effect evaluation of the ground reinforcement technique, which has been widely applied to civil engineering and construction fields, is not established for the guidelines of choosing the efficient evaluation method, and in fact the expects have little effort to determine the reinforcement effect quantitively. This paper presents some results a field test performance of FRP pressure grouting method at a collapsed slope were carried out to verify the improving effect.

• Journal of the Korea institute for structural maintenance and inspection
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• v.3 no.3
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• pp.269-277
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• 1999

The purpose of this study is to investigate the structural behavior of reinforced concrete columns rehabilitated with epoxy-bonded steel plates subjected to axial load. Eleven specimens were made to evaluate structural capacity of reinforced concrete columns rehabilitated with steel plates. This study considers the change of the internal force and the deformation of reinforced concrete column with reinforcing steel plates, and analyzes the effect of the improvement of strength and ductility. Based on the test results, this study brings the following conclusions. In case of the effect of reinforcement by the ratio of the same volume, the internal force for the test model, which the width of the reinforcing steel plate is small, is effectively higher. The smaller the width and the thickness of reinforcing steel plate, the more effective the effect of reinforcement is. For applying the theorical equation by Uzumeri, the maximum load and the coefficient of effective crossing reinforcement by the width and the thickness of steel plate reflected the properties of reinforcing steel plate.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.04a
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• pp.188-189
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• 2022

With the development of nano-reinforcement technology, TiO₂ nanomaterials have received widespread attention as one of the additives without pozzolanic reaction, which can be used to improve the mechanical properties of cement-based materials. Meanwhile, with the development of additive manufacturing technology or known as 3D printing technology, its application in the construction field has also got noticed. Therefore, in this work, the effect of three sizes of TiO₂ on the compressive strength of hardened cement-based materials fabricated by binder jetting 3d printing was evaluated. According to the results, the TiO₂ particles with larger sizes can provide better reinforcement to the hardened cement due to its more significant filling effect.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.337-340
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• 2005

In this study, an effect of fiber blending on material property of Hybrid Fiber Reinforced Concrete (HFRC) was evaluated. Also, Compare and evaluates collating and mechanical property by the mixing rate of fiber for HFRC was determine. Modulus of rupture and strength effectiveness of Hybrid Fiber Reinforced Concrete mixed with macro-fiber(steel fiber) and micro-fiber(glass fiber, carbon fiber, cellulose fiber). Test result shows, in the case of mono fiber reinforced concrete. As the steel fiber mixing rate increases to 1.5$\%$, the strength effectiveness promotion rate rises. However, when is 2.0$\%$, strength decreases. In the case of hybrid fiber reinforcement concrete, synergy effect of micro fiber and macro fiber happens and higher Modulus of rupture and strength effectiveness appears than mono-fiber reinforcement concrete. Use of hybrid fiber reinforcement in concrete caused a significant influence on its fracture behavior; consequently, caused increase by mixing rate of steel fiber + carbon fiber and contributed by steel fiber + glass fiber, steel fiber + celluloid fiber in reinforcement effect in order. And was expose that steel fiber(1.5$\%$) + carbon fiber(0.5$\%$) is most suitable association.

• Steel and Composite Structures
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• v.38 no.4
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• pp.415-430
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• 2021

The effective flange width was usually introduced into elementary beam theory to consider the shear lag effect in steel-concrete composite beams. Previous studies have primarily focused on the effective width under positive moments and elastic loading, whereas it is still not clear for negative moment cases in the normal service stages. To account for this problem, this paper proposed simplified formulas for the effective flange width and reinforcement stress of composite beams under negative moments in service stages. First, a 10-degree-of-freedom (DOF) fiber beam element considering the shear lag effect and interfacial slip effect was proposed, and a computational procedure was developed in the OpenSees software. The accuracy and applicability of the proposed model were verified through comparisons with experimental results. Second, a method was proposed for determining the effective width of composite beams under negative moments based on reinforcement stress. Employing the proposed model, the simplified formulas were proposed via numerical fitting for cases under uniform loading and centralized loading at the mid-span. Finally, based on the proposed formulas, a simplified calculation method for the reinforcement stress in service stages was established. Comparisons were made between the proposed formulas and design code. The results showed that the design code method greatly underestimated the contribution of concrete under negative moments, leading to notable overestimations in the reinforcement stress and crack width.

• Culinary science and hospitality research
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• v.10 no.3
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• pp.83-96
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• 2004

According to construction of global administration environment, all over the world was ended up in infinite competition period. Because eating out company also competes with another company, it must enjoy competitive power high position to secure high position continuously, classified by formation constituent's individuation and two aspects of organic special quality by the factor. Individuation classified by formation constituent's business ability, personal relations, age factors of Information Technology, and organic special quality classifies by factor of formation culture and result that analyze eating out company's business condition competitive power reinforcement effect factor is same as following. First, was construed by company culture, personal relations, business ability period of ten days with family Restaurant, and Information Technology showed that do not influence. Competitive power reinforcement effect factor with special restaurant was construed by company culture, personal relations, business ability period of ten days, and fast food company culture and Information Technology factor with hotel restaurant company culture by competitive power reinforcement effect factor construe.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.4A
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• pp.311-321
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• 2011

To analysis the effect of reinforcement ratio and impact velocity on local damage, a series of impact analyses are performed to predict local effects. According to these results, the reinforcement ratio has no effect on the penetration depth and perforation thickness, but notable change to the scabbing area were observed. The higher the missile velocity becomes, the greater the degree of local damage to the reinforced concrete slabs is. Analysis results will be useful in the impact-resistance design of containment buildings and structures.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.185-188
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• 2008

Flat plate system has structural weakness such as punching shear. Punching shear resistance can be increase by using a lager column section and effective depth, higer concrete compressive strength, and more flexural reinforcement ratio. But using a shear reinforcement is most economical, enable, workable solution in flat plate. The slab with thickness smaller than 250mm can not perform effectively due to insufficient development length of shear reinforcement in the slab. In case of proposed reinforcements, since the shear reinforcements were installed between the top bar and the bottom bar, shear elements generated slip failure before they reached yield. strength. effect of anchorage strength were effective anchorage length, concrete strength, diameter of shear element and anchorage detail. considering effect of slab thickness and concrete strength, formula of K factor propose in thin flat plate slab. by considering effect of anchorage length and concrete strength, strength of shear reinforcement will be computed correctly in thin flat plate slab.