• Journal of the Korea institute for structural maintenance and inspection
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• v.5 no.2
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• pp.103-109
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• 2001

In this paper, the prestressing order of tendons is studied to minimize a bursting force of an anchorage. The bursting forces is a primary factor of anchorage failures. The forces of the anchorage depend on the prestressing order and size of the tendons, if a lot of tendons are introduced to the anchorage. Many studies have been made to analyze the bursting force of the anchorage. However, the studies have been limited to the bursting forces of the anchorage having one or two tendons. PSC box girder bridges usually have a lot of tendons. And the difference of the bursting forces lies in the prestressing order of the tendons. As a result of the lack of studies on the prestressing order for the bridges, the order depends on the designer's intuition and experiences. It may be stated that this study should be useful for determining the reasonable prestressing order of tendons for the PSC box girder bridges.

• The Journal of the Korea Contents Association
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• v.14 no.7
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• pp.511-517
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• 2014

The superstructure type of the railway bridge in our country, is mainly classified into the box girder and the I-type girder. The box girder is widely used in the high speed railway bridge because of the safety due to dynamic behavior. The I-type girder is used in the conventional railway bridge, and is also divided into the general type and the composite type, and the newly modified types have been developed. According to the current railway bridge design code, the girder design by the span length in various railway bridge types are performed in this study. The suitable girder height by the span length are analyzed, and the comparative analysis of the structural efficiency and the economical efficiency is carried out. From this study, the composite type girder is appeared the good result in respect of the structural efficiency. However, in the economical aspect, the general I-type girder is required less cost than the other types.

• Journal of the Korean Society of Safety
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• v.20 no.3 s.71
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• pp.134-142
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• 2005

This study is to find out how organic solvent will be propagated from painting inside the steel box girder of bridge. $2.9m{\times}3.0m$ of inside size of steel box girder is not suitable for painters to do his work comfortably and hygienically. Substance density(ppm)inside the space of the box unsatisfactory hygienical condition. Most of organic solvent(mainly toluene) came down to 0.5m in two minutes and 53sec. But personal protection for painter should be properly kept against flying this heavy organic solvent. longitudinally 27.1m in length is a cell unit of the whole length of bridge. Model XP-3l6A made in Japan is a main instrumentation adjusted to sense organic solvent especially toluene which can be measured up to 10,000ppm. Scenario analysis by computer program, safer release 2.0 has been performed first to estimate how the organic solvent will be propagated. And then actual test was done as a model. This has been measured for approximately five(5) minutes, with 30 sec interval. Actual measurement results showed much higher $10{\sim}20%$ than result analyzed by the computer program, meaning that this painting work can give worse effect to the worker who is painting inside the box girder of the bridge. The first meas urement level over the floor set up at 30cm height from the floor, because organic solvent was estimated to stay at the level. and then, they were measured at 1.0m, 1.5m level respectively, more.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.1040-1045
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• 2004

A study has been performed to investigate on the dynamic behavior of bridges crossed by the KTX(Korea Train eXpress). The investigated bridge is a 2-span continuous concrete box bridge with spans of 40m length named Yeon-Jae bridge. We have performed many field tests on the dynamic behaviors of a real bridge for KTX using various sensors. For this study, various sensors have been installed on the Yeon-Jae bridge located in the experimental section of the KHSR(Korea High-Speed Railway) track and tests have been performed. Through this study, it is known that effects of local modes and sleepers in the box-girder bridge for the KTX on the dynamic responses is remarkable. Therefore, in the investigation on the accelerations of the box-girder bridge, three dimensional model should be adopted in numerical analysis including the effects of sleepers. The effect of temperature on the accelerations of the bridge should be investigated in the further studies to determine the reason of excessive acceleration.

• Journal of the Korea institute for structural maintenance and inspection
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• v.7 no.4
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• pp.109-120
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• 2003

The state-of-art of curved box girder bridge with cross section design has advanced in various area. In these days, several analytical techniques for behaviors of curved box girder bridges cross section are available to engineers. The transfer matrix method is extensively used for the structural analysis because its merit in the theoretical background and applicability. The technique is attractive for implementation on a numerical solution by means of a computer program coded in Fortran language with a few elements. To demonstrate this fact, it gives good results which compare well with finite element method. Therefore, this paper proposed the static analysis method of curved box bridge with cross section by transfer matrix method based on pure-torsional theory and the optimal span ratio/variable cross section ratio of 3 span continuous curved box girder bridge.

• Journal of the Korean Society for Railway
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• v.11 no.5
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• pp.471-476
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• 2008

The superstructure type of the railway bridge in our country, is mainly classified into the box girder and the I-type girder. The box girder is widely used in the high speed railway bridge because of the safety due to dynamic behavior. The I-type girder is used in the conventional railway bridge, and is also divided into the general type and the composite type, and the newly modified types have been developed. According to the current railway bridge design code, the girder design by the span length in various types of railway bridge is performed in is study. The suitable girder height and the construction cost by the span length are analyzed, and the comparative analysis of the structural efficiency and the economical efficiency is carried out. From this study, the composite type girder is appeared the good result in respect of the structural efficiency. However, in the economical aspect, the general I-type girder is required less cost than the other types.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2005.04a
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• pp.249-256
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• 2005

Rigorous FE(Finite Element) analyses of the cable-stayed bridge with steel-box girder, the main construction method of which is FCM (Free Cantilever Method), are presented in this paper. The analysis and the checking of design for a derrick crane under several loading conditions are performed using the software MIDAS/Civil and the beam elements are used to model the main structure. Among all the construction stages, special construction stages are chosen and considered to ensure the safety of segments of box girder The stress analysis for lifting of a segment of box girder is performed using the software SAP2000 and the shell elements of which having 6 DOF(Degrees Of Freedom) per nodes are successfully used to model the segment of box girder for the purpose of capturing the detailed behaviors on the folded-plates in the segment. Finally, concluding remarks are given to improve a design of the derrick crane and the segment based on the results from this study.

• Earthquakes and Structures
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• v.9 no.6
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• pp.1153-1179
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• 2015

This paper focuses on presenting modeling considerations and insight into the performance of typical straight, curved, and skewed box-girder bridges in California which form the bulk of the bridge inventory in the state. Three case study bridges are chosen: Meloland Road Overpass, Northwest Connector of Interstate 10/215 Interchange, and Painter Street Overpass, having straight, curved, and skewed superstructures, respectively. The efficacy of nonlinear dynamic analysis is established by comparing the response from analytical models to the recorded strong motion data. Finally insights are provided on the component behavioral characteristics and shift in vulnerability for each of the bridge types considered.

• Journal of the Korea Concrete Institute
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• v.11 no.3
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• pp.23-34
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• 1999

In designing PSC box girder bridge, the dead load, prestressing force, creep and shrinkage of concrete are the main factors which influence the camber and deflection of segmental concrete structure under construction. Among these factors the creep and shrinkage are the functions of the time-dependent property which, therefore, must considered with time. The prediction model for estimating creep and shrinkage of concrete has been suggested by ACI, CEB/FIP, JSCE and KSCE design code. In this study the creep and shrinkage test were carried out for four curing ages of concrete which was applied to the pretressed concrete box-girder bridge at a construction site, and the results of test were compared to the values of prediction by the design code. Shrinkage test shows that the test results are similar to KSCE-96 and JSCE-96 but very higher than other prediction model and creep test results are generally similar to ACI-209 and DSCE-96 but lower than other prediction models in contrast to shrinkage test.

• Structural Engineering and Mechanics
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• v.46 no.4
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• pp.519-531
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• 2013

To have a better understanding of the torsional mechanism and influencing factors of PC composite box-girder with corrugated steel webs, ultimate torsional strength of four specimens under pure torsion were analyzed with Model Test Method. Monotonic pure torsion acts on specimens by eccentric concentrated loading. The experimental results show that cracks form at an angle of $45^{\circ}$ to the member's longitudinal axis in the top and bottom concrete slabs. Longitudinal reinforcement located in the center of cross section contributes little to torsional capacity of the specimens. Torsional rigidity is proportional to shape parameter ${\eta}$ of corrugation and there is an increase in yielding torque and ultimate torque of specimens as the thickness of corrugated steel webs increases.