• Journal of Distribution Research
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• v.15 no.1
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• pp.73-101
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• 2010

Using data collected from franchisees from Busan, we empirically examined the relationship both structural (tie strength), relational (trust), and cognitive (shared value) of social capital and between those dimensions and the patterns of economic performance and noneconomic performance (relationship continuity intention). So we established 9 hypotheses to test the structural relationship among dimensions of social capital and performances like below. H1: A franchisee's perceived tie strength with its franchisor will positively influence its trust in the franchisor. H2: A franchisee's perceived shared value with its franchisor will positively influence its trust in the franchisor. H3: A franchisee's perceived tie strength with its franchisor will positively influence its economic performance. H4: A franchisee's perceived shared value with its franchisor will positively influence its economic performance. H5: A franchisee's perceived trust in its franchisor will positively influence its economic performance. H6: A franchisee's perceived tie strength with its franchisor will positively influence its relationship continuity intention with the franchisor. H7: A franchisee's perceived shared value with its franchisor will positively influence its relationship continuity intention with the franchisor. H8: A franchisee's perceived trust in its franchisor will positively influence its relationship continuity intention with the franchisor. H9: A franchisee's perceived economic performance will positively influence its relationship continuity intention with the franchisor. The conceptual model specifying the relationship among dimensions of social capital and performances is presented in Fig. 1. Tests of the hypotheses were performed using a structural equation model. This model also reflected a good fit to the data ($\chi^2$=101.12 df=62 p=0.004, RMSEA=0.050 GFI=0.936 AGFI=0.895 NFI=0.959 CFI=0.986). The standardized solution estimated by the AMOS 7 program was for interpreting the structural results (Table 1). As was expected, tie strength and shared value were founded to be significant predictors of trust (H1 supported; H2 supported). Tie strength and trust have a significant positive effect on economic performance (H3 supported; H5 supported). But shared value have not a significant effect on economic performance (H4 Rejected). Tie strength were not associated with relationship continuity intention (H6 Rejected). While on the other higher shared value, trust, and economic performance have a significant effect on the relationship continuity intention (H7 supported; H8 supported; H9 supported). The results show integratedly that, first, tie strength does not affect directly but affects indirectly on relationship continuity intention via trust and economic performance. Second, shared goals affect directly and do indirectly via trust on relationship continuity intention. But shared goals does not affect via economic performance on relationship continuity intention. Finally, the study suggests important implications for both research and practice for franchise system especially.

• Journal of Korean Society of Steel Construction
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• v.22 no.1
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• pp.67-74
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• 2010

The cases of collapse of greenhouses in rural areas have been increasing due to the unexpected heavy snow load. Studies on how to prevent the collapse of greenhouses are rare, however, and the damages are repeated annually. This studysuggests two reinforcing methods: the use of ahigh-strength tapered module, and the addition of a pre-tension tie. The high-strength tapered section is installed where the bending moment is maximum. The design of a plastic greenhouse is controlled by its strength rather than its deflection. The shape of a greenhouse resembles that of an arch system, but its actual structural behavior is the frame behavior, because it is non-continually composed of a curved element (a beam) and vertical elements (columns). This system is too weak and slender to resist a vertical load, because an external load is resisted by the moment rather than by axial force. In this study, a new method, the installation of a temporary tie at the junction of the arch and the column only during snow accumulation, is proposed. The tie changes the action of the greenhouse frame to an arch action. The arch action is more effective when the pre-tension force is applied in the tie, which results in a very strong temporary structural system during snowfall. As a result of using this high-strength tapered section, the combined strength ratio of what? decreased from 10% to 30%. In the case of the additional reinforcement with a tie, it was reduced by half.

• Journal of the Korea Concrete Institute
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• v.13 no.6
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• pp.602-609
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• 2001

A strut-and-tie model was proposed to predict the shear strength of RS beam which is a hybrid steel beam with reinforced concrete ends. The proposed model is capable of considering the concrete softening effects due to diagonal shear cracks at the embedded area of steel in concrete. It can predict tile failure strength of RS beam from the mathematical formulations which are based on equilibrium, compatibility, and the constitutive laws of cracked reinforced concrete. The previous experimental results of 15 RS beams were analyzed with the proposed model and the analytical results were also compared with formulas currently available. The comparison revealed that the proposed model can predict the strength of RS beam better than the others. The average ratio of experimental strengths to analytical results was 1.02 and the standard deviation was 0.126.

• Journal of the Korea Concrete Institute
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• v.15 no.3
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• pp.417-424
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• 2003

A bearing failure in RCS(Reinforced Concrete Column and Steel Beam) system is recognized as one of the distinct joint failure modes for the composite frames. Vertical and transverse reinforcement in addition to concrete are effective for better transfer of vortical forces through concrete bearing. To examine the effect of the vertical bars, tie bars, a U-type detail developed in this study and concrete confinement, local bearing tests were conducted using 22 small-scale concrete block specimens. Test results show that vertical reinforcement and tie bars mainly contribute to the bearing capacity. However larger amounts of tie reinforcement are required than those recommend from ASCE guidelines, to apply the nominal concrete strength as 2 $f_{ck}$ over the bearing area. Cross ties are proved to be highly effective for resisting the vertical forces. Maximum bearing strength can be increased upto 2.5 $f_{ck}$ . An accurate prediction model for bearing strength is proposed for better design of the composite Joint.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.32 no.3
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• pp.165-172
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• 2019

In this study, the shear strength of prestressed concrete deep beams is predicted using finite element analysis, and the variation in the shear strength according to the degree of prestressing is investigated. Numerical analysis results are compared with results obtained by the strut-and-tie model and associated experiments. Numerical analyses are performed on prestressed concrete deep beams with different values of concrete strength, effective prestress, ratio of tensile reinforcement, and shear span to effective depth ratio. The shear strength predicted by the numerical analysis is similar to the experimental value obtained, with an error of less than 5%. However, the strut-and-tie model highly overestimated the shear strength of prestressed concrete deep beams with a concentrated loading area. The ultimate shear capacity of prestressed concrete deep beams increased linearly with increasing prestresss applied to the tendon.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.145-150
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• 2001

With the increase in the use of High-Strength Concrete(HSC) despite the its weakness like brittle characteristic, it is important to improve the performance of HSC columns, nowadays. Therefore, it is common to use higher strength steel in HSC for the purpose of ductility and strength improvement. This experimental study was set up to investigate the inelastic behavior of HSC(700kg/$cm^{2}$) columns subjected to combined axial and repeated lateral loads. Effects of key variables such as the volumetric ratio of transverse reinforcement, tie configuration and tie yield strength are studied in this research program. Test results indicate that inelastic response of HSC columns improve with proper confinement of core concrete. Increasing the amount of transverse reiuorement results in increased ductility.

• Structural Engineering and Mechanics
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• v.27 no.4
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• pp.501-521
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• 2007

This study presents a model to better understand the shear behavior of reinforced concrete walls subjected to lateral load. The scope of the study is limited to squat walls with height to length ratios not exceeding two, deformed in a double-curvature shape. This study is based on limited knowledge of the shear behavior of low-rise shear walls subjected to double-curvature bending. In this study, the wall ultimate strength is defined as the smaller of flexural and shear strengths. The flexural strength is calculated using a strength-of-material analysis, and the shear strength is predicted according to the softened strut-and-tie model. The corresponding lateral deflection of the walls is estimated by superposition of its flexibility sources of bending, shear and slip. The calculated results of the proposed procedure correlate reasonably well with previously reported experimental results.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.349-352
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• 2004

In this study, a strut-and-tie models for the coupling beam based on deformations are presented. To design shear-dominated R/C coupling beams, it is important to consider shear strength deterioration with required deformations. This study proposes the method of estimating shear strength of the reinforced concrete coupling beams. The proposed method determines the strain states from target displacements based on the nonlinear truss analysis. The estimated horizontal strain of beam is then used in calculating the strength of the diagonal strut with compatibility conditions. The deterioration of shear strength of the coupling beam depends on the strength degradation of struts due to plastic deformations.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.269-272
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• 2006

The anchorage zone of prestressed concrete members is a critical region where a large concentrated force due to prestressing by tendons is introduced. In this study, the ACI, AASHTO LRFD, CEB-FIP design criteria and the nonlinear strut-tie model approach are applied to the ultimate strength analysis of simple anchorage zones of 18 post-tensioned concrete members tested to failure. From the result of ultimate strength analysis, the advantages and disadvantages of each method are compared and discussed.

• Structural Engineering and Mechanics
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• v.38 no.4
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• pp.385-403
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• 2011

Continuous deep girders which transmit the gravity load from the upper wall to the lower columns have frequently long end shear spans between the boundary of the upper wall and the face of the lower column. This paper presents the results of tests and analyses performed on three 1:2.5 scale specimens with long end shear spans, (the ratios of shear-span/total depth: 1.8 < a/h < 2.5): one designed by the conventional approach using the beam theory and two by the strut-and-tie approach. The conclusions are as follows: (1) the yielding strength of the continuous RC deep girders is controlled by the tensile yielding of the bottom longitudinal reinforcements, being much larger than the nominal strength predicted by using the section analysis of the girder section only or using the strut-and-tie model based on elastic-analysis stress distribution. (2) The ultimate strengths are 22% to 26% larger than the yielding strength. This additional strength derives from the strain hardening of yielded reinforcements and the shear resistance due to continuity with the adjacent span. (3) The pattern of shear force flow and failure mode in shear zone varies depending on the amount of vertical shear reinforcement. And (4) it is necessary to take into account the existence of the upper wall in the analysis and design of the deep continuous transfer girders that support the upper wall with a long end shear span.