• Steel and Composite Structures
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• v.20 no.6
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• pp.1237-1257
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• 2016

The paper concerns analysis of effects of shrinkage of slab concrete in a steel-concrete composite deck of a through truss bridge span. Attention is paid to the shrinkage alongside the span, i.e., transverse to steel-concrete composite cross-beams. So far this aspect has not been given much attention in spite of the fact that it affects not only steel-concrete decks of bridges but also steel-concrete floors of steel frame building structures. For the problem analysis a two-dimensional model is created. An analytical method is presented in detail. A set of linear equations is built to compute axial forces in members of truss girder flange and transverse shear forces in steel-concrete composite beams. Finally a case study is shown: test loading of twin railway truss bridge spans is described, verified FEM model of the spans is presented and computational results of FEM and the analytical method are compared. Conclusions concerning applicability of the presented analytical method to practical design are drawn. The presented analytical method provides satisfactory accuracy of results in comparison with the verified FEM model.

• Steel and Composite Structures
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• v.18 no.2
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• pp.467-480
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• 2015

The steel-concrete composite decks have high fatigue durability and deformability in comparison with ordinary RC slabs. Withal, the steel-concrete composite deck is mostly heavier than the RC slabs. We have proposed herein a new type of steel-concrete composite deck which is lighter than the typical steel-concrete composite decks. This can be achieved by arranging hollow sectional members as shear connectors, namely, half-pipe or channel shear connectors. The present study aims to experimentally investigate mechanical characteristics of the half-pipe shear connectors under the direct shear force. The shear bond capacity and deformability of the half-pipe shear connectors are strongly affected by the thickness-to-diameter ratio. Additionally, the shear strengths of the hollow shear connectors (i.e. the half-pipe and the channel shear connectors) are compared. Furthermore, shear capacities of the hollow shear connectors equivalent to headed stud connectors are also discussed.

• Journal of Korean Society of Steel Construction
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• v.15 no.4 s.65
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• pp.403-412
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• 2003

The composite metal deck plate system has been widely used for office structures. Recently, however, the flat deck plate has been developed to apply the composite slab system to residential structures. Reduction in construction cost and time can be expected by using expanded metal instead of wire mesh as crack control reinforcements. This study proposed a composite slab system composed of a new-shaped steel deck plate and expanded metal. Twelve specimens were tested to evaluate the structural performance of the new composite slab system. The test results were summarized mainly in terms of maximum load carrying capacity and failure behaviors of each specimen.

• Steel and Composite Structures
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• v.19 no.5
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• pp.1221-1236
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• 2015

Since the coefficients of thermal expansion (CTE) between concrete and GFRP, steel and GFRP are quite different, GFRP laminates with different laminas stacking-sequence present different thermal behavior and currently there is no specification on mechanical properties of GFRP laminates, it is necessary to investigate the thermal influence on composite girder with stay-in-place (SIP) bridge deck at different levels and on different scales. This paper experimentally and theoretically investigated the CTE of GFRP at lamina's and laminate's level on micro-mechanics scales. The theoretical CTE values of laminas and laminates agreed well with test results, indicating that designers could obtain thermal properties of GFRP laminates with different lamina stacking-sequence through micro-mechanics methods. On the basis of the CTE tests and theoretical analysis, the thermal behaviors of composite girder with hybrid GFRP-concrete deck were studied numerically and theoretically on macro-mechanics scales. The theoretical results of concrete and steel components of composite girder agreed well with FE results, but the theoretical results of GFRP profiles were slightly larger than FE and tended to be conservative at a safety level.

• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.5
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• pp.68-77
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• 2012

The joint of existing steel grid composite deck is composed of lap splice of reinforcing bar with end hooks and field-placed concrete. In this study, bending tests of deck joint composed of concrete shear key and high tension bolts are carried out for the design variable, concrete shear key strengthened with steel plate or not, and test results are compared with flexural performance of the existing deck joint. Test results showed that the mechanical deck joint has about 30% ~ 60% more ultimate bending strength than the existing joint. According to analysis results of moment-curvature relationship, the initial bending stiffness of the existing deck joint is some higher than that of mechanical joint. But, after crack failure the structural performance of the existing deck joint is rapidly reduced. Furthermore, the deck joint with the strengthened shear key with steel plate has more bending moment capacity than the deck joint without strengthening. And strengthening of shear key has positive influence on the increase of bending stiffness.

• Proceedings of the Korea Concrete Institute Conference
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• 1995.04a
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• pp.293-298
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• 1995

The strength of shear connectors embedded in lightweight concrete slab with deck plate is influenced by various factors of deck plate, shear conncetor and concrete. Generally, it is reported that the strength of shear connector in lightweight concrete decreases in comparison with that in normal concrete. So this paper is to use compressive strength of lilghtweight concrete, width-height ratio of deck plate, and cross sectional area of shear conncetor as variables, to evaluate the strength of shear conncetors in composite beam of steel and lilghtweight concrete slabs with deck plate, and then to suggest the reasonable strength equation by comparing the push-out test results with establixhed strength formula. As the result of 24 specimens test, in case of lightweight concrete slab with deck plate, it has showed that in the same strength, the strength of shear connector decreased about 10~20% in comparison with that in normal concrete. In spite of lightweight concrete, the test results were closely approached the established strength formula of shear connector using Fisher's reduction coefficient.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05a
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• pp.467-470
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• 2005

This study was performed to evaluate the static strength of long-span PSC deck slabs. In the previous study, the minimum thickness of PSC deck slabs in the composite two-girder bridge was proposed. To examine the structural behavior and safety of the PSC deck slabs designed in accordance with the proposed minimum thickness, 1/3 scaled PSC deck slabs in the composite two-girder bridge were tested under the static loading. The test results were compared with the predicted values proposed by the code and Matsui. Test results showed ultimate static strength of the PSC deck slabs designed in accordance with the proposed minimum thickness have enough margin of safety. The static failure mode of each test specimen was punching shear mode.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.1
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• pp.165-170
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• 2009

In this study, the flexural experiment was conducted to propose the one-way composite slab system composed of concrete and GFRP-Deckplate by comparing with the composite deck slab system with bar-mesh As a result of experiment, the specimens of the proposed GFRP-Deck composite slab were better than the specimens for comparison in the flexural performance. It is effective for the building structures exposed to air pollution or salt.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.493-498
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• 2003

The 3D nonlinear analysis for steel-concrete hybrid deck is carried out by utilizing 2D plane interface element. The effect of the slip occurred between steel and concrete can be modeled by this element. This analysis focuses on not only global behavior of steel-concrete hybrid deck but also local behaviors of members of it such as lower steel plate, I-beam, and concrete which are varied by slip modulus. In this analysis, it was founded that the limit slip modulus could classify the states of steel-concrete hybrid deck into three parts such as full-composite, partial-composite, and non-composite, considering the behavior of lower steel plate, I-beam, and concrete at the mid span and the support as well as the yield load and ultimate load of it.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.19 no.2 s.72
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• pp.203-212
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• 2006

Although composite construction has many mechanical advantages over noncomposite construction, the design of noncomposite construction for skew bridges with large skew angels has been often checked because composite construction caused large stresses in the bridge deck. But there is somewhat difficulty to apply noncomposite construction in the field because of the structural problem such as the slip at the interface between the concrete deck and steel girders. In this study, the validity of the application of the composite construction to skew angles with large skew angles is investigated by analyzing effects of two interactions such as composite and noncomposite actions between the concrete deck and steel girders on the behavior of skew bridges. A series of parametric studies for the total 27 simply supported skew bridges was conducted with respect to parameters such as girder spacing, skew angle, and deck aspect ratio. The improvement of the behavior of composite skew bridges was examined by using the concept of the stiffness adjustment of bearings which I suggested in previous research. Results of analyses show that a more desirable behavior of skew bridges can be obtained from composite construction instead of noncomposite construction and the method of the stiffness adjustment of bearings results in a more rational and economical design of composite skew bridges and substructures.