• Magazine of RCR
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• v.14 no.3
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• pp.33-38
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• 2019

• Steel and Composite Structures
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• v.2 no.6
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• pp.441-460
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• 2002

In the design of bridges, it is important to consider the thermal stresses induced by the non-linear temperature distribution as well as the variation of effective temperature in the bridge deck. To cope with this, design temperature profiles are provided by design codes, which are normally based on extensive research work. This paper presents the results of a comprehensive investigation on the thermal behaviour of bridges in Hong Kong with special emphasis on composite bridges. The temperature distribution in bridges depends primarily on the solar radiation, ambient air temperature and wind speed in the vicinity. Apart from data of the meteorological factors, good estimates of the thermal properties of material and the film coefficients are necessary for the prediction of temperature distribution. The design temperature profiles for various types of composite bridge deck with bituminous surfacing and concrete slab of different thicknesses are proposed. The factors affecting the design effective temperature are also reviewed and suitable values for Hong Kong are proposed. Results are compared with recommendations of the current local code. The method facilitates the development of site-specific temperature profiles for code documents, and it can also be applied to create zoning maps for temperature loading for large countries where there are great climatic differences.

• Journal of the Earthquake Engineering Society of Korea
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• v.10 no.4 s.50
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• pp.85-94
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• 2006

In the design of bridge piers in seismic area, the ductility requirement is the most important factor. In order to enhance the seismic performance of RC columns, it is necessary to make the ductility of columns larger by covering RC columns with steel tubes or confining RC columns by arranging transverse reinforcements such as hoop ties closely. Using core steel composite columns is useful as one of the reinforcing RC columns. In this paper, quasi-static tests on concrete encased composite columns with single core steel or multiple steel elements were performed to investigate the seismic performance of the composite columns. Eight concrete-encased composite specimens were fabricated. The cross-sections of these specimens are composed of concrete-encased H-shaped structural steel columns and a concrete-encased circular tube with partial in-filled concrete. Test parameters were the amount of the transverse reinforcements, type and number of encased steel member. Through the tests, it was evaluated the ductility of SRC composite specimens. It has become clear from the test results that encased steel elements makes the deformation capacity of the columns to be larger. The displacement ductility and lateral strength of specimen with concrete-encased circular tube were indicated the biggest value.

• Steel and Composite Structures
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• v.22 no.3
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• pp.537-565
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• 2016

Australian railway networks possess a large amount of aging timber components and need to replace them in excess of 280 thousands $m^3$ per year. The relatively high turnover of timber sleepers (crossties in a plain track), bearers (skeleton ties in a turnout), and transoms (bridge cross beams) is responsible for producing greenhouse gas emissions 6 times greater than an equivalent reinforced concrete counterparts. This paper presents an innovative solution for the replacement of aging timber transoms installed on existing railway bridges along with the incorporation of a continuous walkway platform, which is proven to provide environmental, safety and financial benefits. Recent developments for alternative composite materials to replace timber components in railway infrastructure construction and maintenance demonstrate some compatibility issues with track stiffness as well as structural and geometrical track systems. Structural concrete are generally used for new railway bridges where the comparatively thicker and heavier fixed slab track systems can be accommodated. This study firstly demonstrates a novel and resilient alterative by incorporating steel-concrete composite slab theory and combines the capabilities of being precast and modulated, in order to reduce the depth, weight and required installation time relative to conventional concrete direct-fixation track slab systems. Clear benefits of the new steel-concrete composites are the maintainability and constructability, especially for existing railway bridges (or brown fields). Critical considerations in the design and finite element modelling for performance benchmarking of composite structures and their failure modes are highlighted in this paper, altogether with risks, compatibilities and compliances.

• Journal of the Korean Society of Industry Convergence
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• v.9 no.3
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• pp.215-220
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• 2006

Recently, steel-concrete composite slab decks have been widely used as highway bridge decks. In the construction of the composite slab decks, it is necessary to join two adjacent blocked bottom plates to form one unite in the longitudinal direction. In this paper, several types of longitudinal direction joints for Robinson type composite slab decks ared proposed herein and static bending test are carried out by using slab specimens. And the stress and deformation of the tensile grip connection with high strength bolts are discussed by using three-dimensional elastic-plastic FEM.

• Steel and Composite Structures
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• v.2 no.1
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• pp.51-66
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• 2002

Perforated shear connectors currently used in composite steel and concrete structures are described and evaluated. Modifications of the perforated connector suitable for common use injavascript:confirm_mark('abe', '1'); civil and bridge engineering are proposed. The connectors were tested in laboratories of CTU Prague for shear load capacity. Push tests of connectors with 32 mm openings and with 60 mm openings, both in normal and lightweight concrete of different strength characteristics and with different transverse reinforcement, were carried out. The experimental study also dealt with the connector height and parallel arrangement of two connectors and their influence on shear resistance. While extensive tests with static loading were carried out, fatigue tests under repeated loading are still in progress. After statistical evaluation of the experimental results and comparisons with other available data the authors developed reasonable shear resistance formulas for all proposed arrangements.

• Journal of Korean Society of Steel Construction
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• v.12 no.2 s.45
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• pp.123-131
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• 2000

In this study, both experimental and analytical study for behavior of the existing composite steel box girder bridges, constructed along with the procedure of continuous placing slab, are conducted to establish the validity of the proposed model. The layer approach is adopted to determine the equilibrium condition in a section to consider the different material properties and concrete cracking across the sectional depth, and the beam element stiffness is constructed on the basis of the assumed displacement field formulation and the 3-points Gaussian Integration. In addition, the effects of creep and shrinkage of concrete for time-dependent behavior of the bridge are taken into consideration. Finally, both analytical and experimental results are compared.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.2
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• pp.634-643
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• 2010

In this study, both an experimental test and a time history analysis with 3D modeling were performed to verify the structural analysis model in a 2-span two girder bridge of high speed railway, which was under constructed according to the ballast load of track structure. In the basis of the structural analysis model, the analysis of construction step was carried out to investigate the reduction effect of moment in middle support of the bridge which has initial prestressing force according to camber control. The initial prestressing force of proper level was calculated, and then the reduction of moment for economical bridge section was studied. Finally, a bridge analysis method was presented for an economical and efficient design in steel composite bridge.

• Journal of the Korean Society of Safety
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• v.23 no.2
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• pp.87-97
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• 2008

The Ilsun Bridge is the world's longest box girder bridge(801m) with corrugated steel webs and has the widest width($21.2{\sim}30.9m$: tri-cellular cross section) among these kinds of composite girder bridges. It has fourteen spans(50m, 10 at 60m, 50m, 2 at 50.5m) where twelve spans are erected by the incremental launching method and two spans by full staging method. Special topics related to the structural safety of prestressed concrete box girder bridge with corrugated steel web in construction stage and service were reviewed. Investigations focus on the span-to-depth ratio, shear stress of corrugated steel webs and optimization of tile length of steel launching nose. The span-to-depth ratio of Ilsun bridge has been found to be well-planned while the corrugated steel web has been designed highly conservative and it has been observed that the conventional nose-deck interaction equation do not fit well with corrugated steel web bridges. As a result, detailed construction stage analysis was performed to check the stress levels and the safety of preceding design conditions. Finally, from the design review of Ilsun bridge, this study suggests optimal design issues which should be of interest in designing a prestressed concrete box girder bridge with corrugated steel webs.

• Steel and Composite Structures
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• v.21 no.1
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• pp.109-122
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• 2016

Concrete creep, while significantly changing the static behaviors of concrete filled steel tube (CFST) structures, do alter the structures' dynamic behaviors as well, which is studied quite limitedly. The attempt to investigate the influence of concrete creep on the dynamic property and response of CFST arch bridges was made in this paper. The mechanism through which creep exerts its influence was analyzed first; then a predicative formula was proposed for the concrete elastic modulus after creep based on available test data; finally a numerical analysis for the effect of creep on the dynamic behaviors of a long-span half-through CFST arch bridge was conducted. It is demonstrated that the presence of concrete creep increases the elastic modulus of concrete, and further magnifies the seismic responses of the displacement and internal force in some sections of the bridge. This influence is related closely to the excitation and the structure, and should be analyzed case-by-case.