• Journal of the Korea institute for structural maintenance and inspection
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• v.13 no.2 s.54
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• pp.129-136
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• 2009

The paper presents an algorithm of selecting optimal locations for measuring displacements(OLD) to adjust cable tension forces during the construction of cable-stayed bridges. The rank for optimal locations can be determined from the effective independence distribution vectors(EIDV) that are computed from the Fisher Information Matrices(FIM) formulated with the displacement sensitivities. To examine the efficiency and reliability of the proposed algorithm for determining OLD, a simulation study on a cable-stayed bridge has been carried out. The results using FIM formulated with displacements are compared with those using FIM with displacement sensitivities through the simulation study. The effects of measurement noise and error in cable length on the adjustment of cable tension forces are evaluated statistically by applying the Monte Carlo scheme.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.2A
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• pp.137-148
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• 2010

This study proposes the optimal ratio of vertical load-carrying capacity (${\beta}$) by investigating structural performances and economic efficiency in the extradosed bridges. Without design standards for the extradosed bridge, Japanese design standards have been used domestically. For the design live load, DL24 is found to be more adequate than DB24. Using the DL24 load, parameter studies are carried out. The parameters are 'main tower height', 'main girder stiffness', and 'cable arrangement'. As a result, it is found that one side cable-stayed extradosed bridges are more economical than double side cable-stayed extradosed bridges. This study also shows that when the ratio of vertical load-carrying capacity(${\beta}$) is 30~50% in the extradosed bridge with the ratio of tower height to main span length 1/6, the extradosed bridge is most economical because of the cable stress less than the allowable stress.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.105-106
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• 2010

FBG temperature sensor and strain sensor has been used to monitoring shrinkage and temperature of concrete cable-stayed girder bridge site in its casting early age, The monitoring method using this study is expected to used a practical method.

• International conference on construction engineering and project management
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• 2011.02a
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• pp.157-161
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• 2011

BIM having started from architecture is being used in civil structure, but there are very few examples despite its effectiveness. In this paper, based on BIM technology, it is presented the method and result of developing web-based 5D system connecting cost, schedule and 3D model from the cable-stayed bridge. Through the system, the user can understand easily schedule on specific time and during some period and extract cost directly. This system also can manage various data types such as drawings, 3D models, documents and photos, for enhanced communication between stakeholders.

• Magazine of the Korea Concrete Institute
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• v.19 no.5
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• pp.58-61
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• 2007

• Magazine of the Korea Concrete Institute
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• v.23 no.4
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• pp.58-63
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• 2011

• Journal of Korean Society of Steel Construction
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• v.25 no.4
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• pp.335-346
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• 2013

AASHTO LRFD and Korean Bridge Design Code (Limit State Design) specify to consider Truck and Lane load simultaneously determined from reliability-based live load model, and impact shall be applied to the truck load while it shall not be applied to the lane load. In this paper, vehicle-bridge interaction analysis under moving truck and lane loads were performed to estimate impact factor of the cables and girders for the selected multi-cable-stayed composite bridges with 230m, 400m and 540m main span. A 6-d.o.f. vehicle was used for truck load and a series of single-axle vehicles was applied to simulate equivalent lane load. The effect of damping ratio on the impact factor was estimated and then the essential parameters to impact factor, i.e., road surface roughness and vehicle speed were considered. The road surface roughness was randomly generated based on ISO 8608 and it was applied to the truck load only in the vehicle-bridge interaction analysis. The impact factors evaluated from dynamic interaction analysis were also compared with those by the influence line method that is currently used in design practice to estimate impact factor in cable-stayed bridge.

• Wind and Structures
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• v.3 no.4
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• pp.267-277
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• 2000

This paper aims to describe the aerodynamic vibrations of various structural elements of bridges, which are particular issues at present. The aerodynamic countermeasures for those vibrations are also discussed considering the generation mechanisms of the aerodynamic instabilities. In this paper, an example of vortex-induced oscillation of bridge deck and its lesson are discussed. Next, the wind-induced cable vibration and its aerodynamic countermeasures are reviewed. Then, the aerodynamic characteristics on two edge girders and their feasibility for application to long span cable-stayed bridges are considered. Furthermore, the bridge decks for future long span bridges are proposed and their aerodynamic characteristics are also discussed.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1994.10a
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• pp.95-102
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• 1994

This paper presents a Cable Stayed Bridge Construction Management System, which consists of Structural System Identification Method (SSIM), Error Sensitivity Analysis and Optimum Error Adjustment & Prediction System. The 1st System Identification Method builds an error influence matrix using the linear superposition of each error modes. The 2nd SSIM also considers the second error mode term, which shows good error factor estimation. The optimal cable adjustment can be accomplished within the allowable range of both cable tension and camber. The Post processor, constituted with Motif and GL library on SGI platform, is useful for monitoring construction stage management by displaying construction data, adjustment and prediction results at each construction step.

• Smart Structures and Systems
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• v.14 no.6
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• pp.1173-1196
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• 2014

Real-time dynamic substructuring tests have been conducted on a cable-deck system. The cable is representative of a full scale cable for a cable-stayed bridge and it interacts with a deck, numerically modelled as a single-degree-of-freedom system. The purpose of exciting the inclined cable at the bottom is to identify its nonlinear dynamics and to mark the stability boundary of the semi-trivial solution. The latter physically corresponds to the point at which the cable starts to have an out-of-plane response when both input and previous response were in-plane. The numerical and the physical parts of the system interact through a transfer system, which is an actuator, and the input signal generated by the numerical model is assumed to interact instantaneously with the system. However, only an ideal system manifests a perfect correspondence between the desired signal and the applied signal. In fact, the transfer system introduces into the desired input signal a delay, which considerably affects the feedback force that, in turn, is processed to generate a new input. The effectiveness of the control algorithm is measured by using the synchronization technique, while the online adaptive forward prediction algorithm is used to compensate for the delay error, which is present in the performed tests. The response of the cable interacting with the deck has been experimentally observed, both in the presence of delay and when delay is compensated for, and it has been compared with the analytical model. The effects of the interface delay in real-time dynamic substructuring tests conducted on the cable-deck system are extensively discussed.