• Korean Journal of Construction Engineering and Management
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• v.7 no.1 s.29
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• pp.64-72
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• 2006

The participants of steel works should exchange a variety of information with others through documents. However construction steel works in the multistage contract system has a difficulty in exchanging information through the documents promptly. So if the trouble as change orders arise, conducting steel works will take much time, and the participants may not discuss the trouble sufficiently. Consequently this study improved the current business process of steel works. And this developed business support system(XCOS) based on XML so that participants of steel works achieve a successful management of steel works through conducting business rapidly and correctly.

• Steel and Composite Structures
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• v.25 no.4
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• pp.427-442
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• 2017

This paper presents unprecedented damped oscillation behaviours of a precast steel-concrete composite slab panel for track support. The steel-concrete composite slab track is an innovative slab track, a form of ballastless track which is becoming increasingly attractive to asset owners as they seek to reduce lifecycle costs and deal with increasing rail traffic speeds. The slender nature of the slab panel due to its reduced depth of construction makes it susceptible to vibration problems. The aim of the study is driven by the need to address the limited research available to date on the dynamic behaviour of steel-concrete composite slab panels for track support. Free vibration analysis of the track slab has been carried out using ABAQUS. Both undamped and damped eigenfrequencies and eigenmodes have been extracted using the Lancsoz method. The fundamental natural frequencies of the slab panel have been identified together with corresponding mode shapes. To investigate the sensitivity of the natural frequencies and mode shapes, parametric studies have been established, considering concrete strength and mass and steel's modulus of elasticity. This study is the world first to observe crossover phenomena that result in the inversion of the natural orders without interaction. It also reveals that replacement of the steel with aluminium or carbon fibre sheeting can only marginally reduce the natural frequencies of the slab panel.

• International journal of steel structures
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• v.18 no.5
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• pp.1639-1653
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• 2018

Bolted connections are suitable due to high quality prefabrication in the factory and erection in the workplace. Prefabrication and modularization cause high speed of erection and fabrication, high quality and quick return of investment. Their technical hitches transportation can be removed by prefabrication of joints and small fabrication of components. Box-columns are suitable members for bolted structures such as welded steel structures with moment frames in two directions etc., but their continual fabrication in multi-story buildings and performing the internal continuity plate in them will cause some practical dilemmas. The details of the proposal technique introduced here, is to remove such problems from the box columns. Besides, some other advantages include new prefabricated bolted beam-to-column connections referred to BBCC. This connection is a set of plates joined to columns, beams, support, and bolts. For a better understanding of its fabrication and erection techniques, two connection and one structural maquettes are made. The present work aims to study the cyclic behavior of connection numerically. To verify the accuracy of model, a similar tested connection was modelled. Its verification was then made through comparison with test results. The behavior of connection was evaluated for an exterior connection using three different support shapes. The effects of support shapes on rigidity, ductility, rotation capacity, maximum strength, four rad rotation strength were compared to those of the AISC seismic provision requirements. It was found that single beams support has all the AISC seismic provision requirements for special moment frames with and without a continuity plate, and box with continuity plate is the best support in the BBCC connection.

• Journal of the Korean Geotechnical Society
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• v.26 no.6
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• pp.45-56
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• 2010

This paper presents the results of a numerical investigation on the behavior of deep excavation wall system supported by steel pipe struts. A series of three-dimensional finite element analyses were carried out on a braced excavation case which adopted steel pipe struts. The results indicated that the mechanical behavior of the steel pipe supported braced excavation is comparable to that of a conventional H-pile supported excavation, although the steel pipe supported system allows a larger longitudinal spacing than the conventional H-pile strut system. Also shown is that the sectional stresses of the steel pipe support system are within the allowable values. This implies that the steel pipe support system can be effectively used as an alternative to conventional H-pile support system.

• Journal of Industrial Technology
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• v.22 no.B
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• pp.199-209
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• 2002

This research is experimental thesis to prepare the structural safety of the upper bridge for support type on tunnel and the effect of settlement. Unit weight test and uni-axial compression test have been performed to simulate the physical property of foundation on the tunnel. Tunnel model of slip form type for centrifuge model has been developed to performed the tunnel excavation while field stress is activated. And the support type of tunnel such as umbrella arch method and large diameter steel pipe reinforce method has been tested for the centrifuge model. After the analysis of experiment, results show that internal displacement of large diameter steel pipe reinforce method is smaller than that of the umbrella arch method.

• Steel and Composite Structures
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• v.4 no.1
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• pp.49-75
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• 2004

The paper derives, validates and illustrates the application of GBT-based formulae to estimate distortional critical lengths and bifurcation stress resultants in cold-formed steel rack-section columns, beams and beam-columns with arbitrarily inclined mid-stiffeners and four support conditions. After a brief review of the Generalised Beam Theory (GBT) basics, the main concepts and procedures employed to obtain the formulae are addressed. Then, the GBT-based estimates are compared with exact results and, when possible, also with values yielded by formulae due to Lau and Hancock, Hancock and Teng et al. A few remarks on novel aspects of the rack-section beam-column distortional buckling behaviour, unveiled by the GBT-based approach, are also included.

• Steel and Composite Structures
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• v.27 no.5
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• pp.647-659
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• 2018

Through extensive research, there exist a new type of connection between railway bridge girders and steel-concrete composite panels. In addition to conventional shear connectors, newly developed blind bolts have been recently adopted for retrofitting. However, the body of knowledge on their influence and application to railway structures has not been thoroughly investigated. This study has thus placed a particular emphasis on the application of blind bolts on the Sydney Harbour Bridge as a feasible alternative constituent of railway track upgrading. Finite element modeling has been used to simulate the behaviours of the precast steel-concrete panels with common types of bolt connection using commercially available package, ABAQUS. The steel-concrete composite track slabs have been designed in accordance with Australian Standards AS5100. These precast steel-concrete panels are then numerically retrofitted by three types of most practical bold connections: head studded shear connector, Ajax blind bolt and Lindapter hollow bolt. The influences of bolt connections on load and stress transfers and structural behaviour of the composite track slabs are highlighted in this paper. The numerical results exhibit that all three bolts can distribute stresses effectively and can be installed on the bridge girder. However, it is also found that Lindapter hollow bolts are superior in minimising structural responses of the composite track slabs to train loading.

• Geomechanics and Engineering
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• v.19 no.1
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• pp.61-70
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• 2019

Yieldable steel ribs have been widely applied in tunnels excavated in rheological rocks. For further understanding the influence of yieldable steel ribs on supporting effect, mechanical behavior of tunnels supported by them in rheological rocks is investigated in this paper. Taking into account the deformation characteristic of yieldable steel ribs, their deformation is divided into three stages. In order to modify the stiffness of yieldable steel ribs in different deformation stages, two stiffness correction factors are introduced in the latter two stages. Viscoelastic analytical solutions for the displacement and pressure in the rock-support interface in each deformation stage are obtained. The reliability of the theoretical analysis is verified by use of numerical simulation. It could be concluded that yieldable steel ribs are able to reduce pressure acting on them without becoming damaged through accommodating the rock deformation. The influence of stiffness correction factor in yielding deformation stage on pressure and displacement could be neglected with it remaining at a low level. Furthermore, there is a linearly descending relationship of pressure with yielding displacement in linear viscoelastic rocks.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.2
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• pp.66-73
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• 2021

In the existing study of steel beams with openings, openings are located at a location where the distance to the support point is equal to or greater than the section height. Considering the facilities using the openings in the steel beam, the distance from the opening to the support point may be closer than the height of the beam section. Therefore, research on this is needed. This study is an experimental study to understand the structural performance of beams with openings close to the ends subjected to Cyclic Loading. In addition, in this study, we want to understand the structural performance through experiments on beams with openings reinforced with vertical or horizontal steel plates.

• Journal of Energy Engineering
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• v.23 no.2
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• pp.35-41
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• 2014

The present study has been carried out to reduce the heat loss from a refrigerator by numerical heat transfer analysis and temperature measurement experiment for the verification of heat transfer analysis result. To perform this purpose, two dimensional heat transfer analysis and measurement of temperature on the surface of freezer for the horizontal cross sectional plane of a refrigerator has been accomplished. From the present study, it could be seen that the steel support in the mullion near gasket region has a heat transfer characteristics which transfer outside heat well from the high temperature hotline and outside air to the inner refrigerator. The effect of removing steel support on the reducing heat loss of a refrigerator was 24.8% and removing steel support might introduce significant improvement of refrigerator heat loss.