• Journal of the Korea Concrete Institute
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• v.13 no.5
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• pp.430-437
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• 2001

Recently, there have been increased much concerns about repair and rehabilitation works for aged concrete structures. It is in particular known that due to repeated overburden vehicles, there are significantly increasing number of aged concrete bridge slabs, which are strongly needed to construct and rehabilitate by innovative construction method. The objective of this research is to develop the new construction method of concrete slab in bridge superstructure, which can contribute to minimize a traffic congestion during repair and rehabilitation works of aged concrete slab, and can sufficiently assure the quality through the minimization of in-situ works at the site. I-beams with punch holes, which are substituted instead of main reinforcing steels in concrete slabs, can be manufactured in accordance with the specification in the factory, and be preassembled into the panel. After erecting the preassembled panels in the site, concrete will be poured into the slab panel. This research is to investigate mechanical properties of I-beam with punch holes itself, and then to investigate structural properties of assembled I-beam panels through static test, of which result can be utilized for the development of the new constructional method for concrete slab in bridge superstructure.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.4
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• pp.10-21
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• 2014

The joint of prefabricated steel grid composite deck is composed of concrete shear key and high-tension bolts. The flexural and shear strength of the joint were experimentally evaluated only by the bending and push-out test of the joint element. In this study the lateral load transfer behavior of the joint in deck structure system is experimentally evaluated. Several decks connected by the joint are prefabricated and loaded centrically and eccentrically. In the case of centrically loaded specimens, the analysis results show that for the same loading step the rotation angle of the joint with 4 high-tension bolts is larger than the case of the joint with 9 high-tension bolts. Consequently, flexural stiffness of deck and lateral load transfer decrease in the case of specimen with 4 high-tension bolts. But, in the case of eccentrically loaded specimens, it is found that there are no significant differences in the load transfer behavior. The further analysis results about the structural behavior of the joint show that lateral load transfer can be restricted by the load bearing capacity of the joint as well as punching shear strength of the slab. Furthermore, considering that high-tension bolts in the joint didn't reach to the yielding condition until the punching shear failure, increase in the number of high-tension bolts from 4 to 9 has a greater effect on the flexural stiffness of the joint and deck system than the strength of them.

• Journal of Korean Society of Steel Construction
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• v.16 no.3 s.70
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• pp.325-332
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• 2004

Cross sections of steel-plate girder bridges are divided into three cross sections of non-composite, partially composite, and fully composite sections, according to their composite characteristics. The Korean provision for the partially and fully composite sections specifies general usage of the stud of shear connectors, whereas the one for the non-composite section specifies empirical usage of slab anchors. However, the actual behavior of the cross sections of steel-plate girder bridges using slab anchors is close not to the non-composite action, but to the partially composite action. Therefore analytical and experimental studies on partial composites of steel-plate girder bridges using slab anchors are performed in this study. Intial stiffness of the slab anchor is obtained by the experimental study for the first time, and the composite characteristic of simple-span and two-span continuous steel-plate girder bridges is investigated by the finite element analyses for the second time. Based on the obtained initial stiffness, the reduction effect of tensile stresses in the concrete-slab on the intermediate support of the continuous bridge is also considered herein.

• Journal of Korean Society of Steel Construction
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• v.12 no.1 s.44
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• pp.17-28
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• 2000

The current specifications for bridge decks requires the same amount of upper and lower reinforcement mats. There have been many empirical activities that the partial elimination of upper reinforcing bars was not caused the structural integrity of a deck. A simplified method is derived based on thin plate theory for three and four-girder-span bridge decks. A simplified method for bridge deck considering the effect of girder deflection is proposed based on a closed-form solution that shows good agreement with the results of finite element models. In this research, a new design approach for deck slabs is proposed based on the simplified method. The negative bending moments in a deck can be evaluated with the simplified method based on the position of a wheel load, the aspect ratio and relative stiffness and the span length. This new approach can lead to a significant reduction of the quantity of the top reinforcing steel bars in a deck. Reducing the quantify of the top reinforcement not only reduces the construction costs for bridge decks, but also reduces the corrosion of reinforcement to a minimum.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.4
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• pp.84-93
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• 2016

The signal characteristic of radar wave on concrete decks is determined by the attenuation of the radar due to the conversion of EM(Electromagnetic) energy to thermal energy through electrical conduction, dielectric relaxation, scattering, and geometric spreading. In this study, it is found that the attenuation of radar signal received on top rebars in bare deck concrete with 2 way travel time shows a general decreasing linear trend because of its same relative permittivity and conductivity. The radar signal after depth-normalization, can then be interpreted as being principally influenced by the content of chlorides penetrating cover concrete, which caused corrosion of rebars in bridge decks.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.5A
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• pp.719-727
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• 2008

The tensile and bond performance of GFRP rebar are different from those of conventional steel reinforcement. It requires some studies on concrete members reinforced with GFRP reinforcing bars to apply it to concrete structures. GFRP has some advantages such as high specific strength, low weight, non-corrosive nature, and disadvantage of larger deflection due to the lower modulus of elasticity than that of steel. Bridge deck is a preferred structure to apply FRP rebars due to the increase of flexural capacity by arching action. This paper focuses on the behavior of concrete bridge deck reinforced with newly developed GFRP rebars. A total of three real size bridge deck specimens were made and tested. Main variables are the type of reinforcing bar and reinforcement ratio. Static test was performed with the load of DB-24 level until failure. Test results were compared and analyzed with ultimate load, deflection behavior, crack pattern and width.

• Journal of Korean Association for Spatial Structures
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• v.6 no.3 s.21
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• pp.93-101
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• 2006

Recently the floor vibration of apartment is often beginning to make its appearance of the environmental dispute, the standard floor system of housing are suggested for the settlement of this issue by government. For the slab vibration analysis on the laminated floor system of apartment, it is required the effectively analytical method of the floor system considering laminated theory. In this paper, more effective modeling methods of laminated floor slab are proposed for the method of accurate rigidity evaluation. By using the advanced modeling method, the more accurate vibration response can be obtained and can accurately evaluate the rigidity of living room floor system of apartment with different laminated materials.

• Journal of the Korea institute for structural maintenance and inspection
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• v.13 no.3 s.55
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• pp.145-154
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• 2009

Steel-Concrete Composite Deck with I-beam welded is lighter and easier to construct than conventional in situ reinforced concrete slabs due to the I-beam embedded in the corrugated slab. For the calculation of effective flexural rigidity of conventional reinforced concrete structures, methods suggested in Design Standard for Roads and Bridges and ACI have been used. In this paper, the calculation methods were applied to steel-concrete composite deck with I-beam welded and then results of the steel-concrete composite deck were compared with those of reinforced concrete slabs. In addition, applicability of the methods to steel-concrete composite deck with I-beam welded was estimated. In order to compare the effective flexural rigidity, flexural experiments were conducted. Fifteen slabs were built and the variables considered in the experiments were studs, length of the slab, shape of the section and connecting methods.

• Journal of Korean Society of Steel Construction
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• v.10 no.4 s.37
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• pp.759-767
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• 1998

Full-depth precast concrete deck bridge has shear pockets for shear connectors that give composite action with steel girder. Strength and shear stiffness of shear connection that is needed to design shear connectors in case that shear pockets are filled with nonshrink mortar are investigated. In case that simple span full-depth precast concrete deck bridge is designed by allowable stress design, distribution of shear connector is suggested and details of precast panel that is placed on the support are proposed. Appropriate distribution of shear connectors in strength design and fatigue design is investigated through parameter analyses using partial interaction theory. The effects of nonshrink mortar strength is studied using the results of experiments and analyses and adequate strength is proposed.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.1
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• pp.85-93
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• 2019

Structural performance and serviceability of precast deck system are mostly determined by connection details between precast decks. Particularly, since the bridge deck is under repeated loads such as traffic loads, fatigue behavior and performance of joints should be investigated. In this study, a two-girder continuous composite bridge specimen was fabricated using the asymmetric ribbed loop joints, and static and fatigue load tests were conducted to evaluate the structural behavior and the crack pattern of the bridge deck. From the test results, the proposed precast deck system resulted in sufficient fatigue performance and failure strength. Therefore, the proposed precast deck system can be applied to the connection part of precast decks effectively.