• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2004.04a
• /
• pp.439-446
• /
• 2004

In this study, the characteristic of the Near Fault Ground Motion which was not considered at the seismic design in our country and how the Near Fault Ground Motion affects the cable-stayed bridge which have long period is analyzed through the dynamic response analysis. So, the object of this study is following that it makes the data which can be utilized as the seismic safety evaluation in case of the cable-stayed bridge taken the near fault in the future.

• Steel and Composite Structures
• /
• v.15 no.1
• /
• pp.15-39
• /
• 2013

The sensitivities of a structural response due to variation of its design parameters are prerequisite in the majority of the algorithms used for fundamental problems in engineering as system uncertainties, identification and probabilistic assessments etc. The paper presents the concept of probabilistic sensitivity of suspension bridges with respect to near-fault ground motion. In near field earthquake ground motions, large amplitude spectral accelerations can occur at long periods where many suspension bridges have significant structural response modes. Two different types of suspension bridges, which are Bosporus and Humber bridges, are selected to investigate the near-fault ground motion effects on suspension bridges random response sensitivity analysis. The modulus of elasticity is selected as random design variable. Strong ground motion records of Kocaeli, Northridge and Erzincan earthquakes are selected for the analyses. The stochastic sensitivity displacements and internal forces are determined by using the stochastic sensitivity finite element method and Monte Carlo simulation method. The stochastic sensitivity displacements and responses obtained from the two different suspension bridges subjected to these near-fault strong-ground motions are compared with each other. It is seen from the results that near-fault ground motions have different impacts stochastic sensitivity responses of suspension bridges. The stochastic sensitivity information provides a deeper insight into the structural design and it can be used as a basis for decision-making.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.28 no.12
• /
• pp.13-17
• /
• 2014

In this paper, the risk of electric shock is analyzed through analysis for characterization of potential distribution analysis and ground fault current analysis near the area where there are occurred a ground fault at electric vehicle wireless charging system using 20kHz. Studies for electric vehicle wireless charging system are in the works for development of efficiency increase, pickup shape design and communication module as a fundamental research step. But the research related to electrical safety and is still scarce state so that more studies are necessary to commercialize. As a result of analysis, it is verified that induced voltage is arisen more up to 45V near the a area of accident during ground fault and fault current has been maintained continuously without clearing fault condition by operating characteristics for circuit breaker and inverter.

• Geomechanics and Engineering
• /
• v.24 no.5
• /
• pp.443-456
• /
• 2021

Structural design of the vertical displacements and shear strains in the earth fill (EF) dams has great importance in the structural engineering problems. Moreover, far fault earthquakes have significant seismic effects on seismic damage performance of EF dams like the near fault earthquakes. For this reason, three dimensional (3D) earthquake damage performance of Oroville dam is assessed considering different far-fault ground motions in this study. Oroville Dam was built in United States of America-California and its height is 234.7 m (770 ft.). 3D model of Oroville dam is modelled using FLAC3D software based on finite difference approach. In order to represent interaction condition between discrete surfaces, special interface elements are used between dam body and foundation. Non-reflecting seismic boundary conditions (free field and quiet) are defined to the main surfaces of the dam for the nonlinear seismic analyses. 6 different far-fault ground motions are taken into account for the full reservoir condition of Oroville dam. According to nonlinear seismic analysis results, the effects of far-fault ground motions on the nonlinear seismic settlement and shear strain behaviour of Oroville EF dam are determined and evaluated in detail. It is clearly seen that far-fault earthquakes have very significant seismic effects on the settlement-shear strain behaviour of EF dams and these earthquakes create vital important seismic damages on the swelling behaviour of dam body surface. Moreover, it is proposed that far-fault ground motions should not be ignored while modelling EF dams.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2007.06a
• /
• pp.39-40
• /
• 2007

The analysis of fault current limiting characteristics according to variation of fault current level in the integrated three-phase flux-lock type superconducting fault current limiter (SFCL), which consisted of three-phase flux-lock reactor wound on an iron core with the same turn's ratio between coil 1 and coil 2 for each single phase, was performed. To analyze the current limiting characteristics of this integrated three-phase flux-lock type SFCL, the short circuit experiments was carried out the various three-phase faults such as the single line-to-ground fault, the double line-to-ground fault, the triple line-to-ground fault. From the experimental results, the fault current limiting characteristic was improved according to increase of fault current level.

• Journal of Electrical Engineering and Technology
• /
• v.2 no.4
• /
• pp.434-440
• /
• 2007

This paper proposes a fault location algorithm for double-circuit transmission lines in the case of single line-to-ground fault. The proposed algorithm requires the voltage and current from the sending end of the transmission line. The fault distance is simply determined by solving a second order polynomial equation which is achieved directly by the analysis of the circuit. In order to testify the performance of the proposed algorithm, several other conventional approaches have been taken out to compare with it. The test results corroborate its superior effectiveness.

• Journal of the Earthquake Engineering Society of Korea
• /
• v.27 no.2
• /
• pp.83-90
• /
• 2023

The recent increase in earthquake activities has highlighted the importance of seismic performance evaluation for civil infrastructures. In particular, the container crane essential to maintaining the national logistics system with port operation requires an exact evaluation of its seismic response. Thus, this study aims to assess the seismic vulnerability of container cranes considering their seismic characteristics. The seismic response of the container crane should account for the structural members' yielding and buckling, as well as the crane wheel's uplifting derailment in operation. The crane's yielding and buckling limit states were defined using the stress of crane members based on the load and displacement curve obtained from nonlinear static analysis. The derailment limit state was based on the height of the rail, and nonlinear dynamic analysis was performed to obtain the seismic fragility curves considering defined limit states and seismic characteristics. The yield and derailment probabilities of the crane in the near-fault ground motion were approximately 1.5 to 4.7 and 2.8 to 6.8 times higher, respectively, than those in the far-fault ground motion.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.60 no.2
• /
• pp.459-463
• /
• 2011

In this paper we reported the characteristics of 1 line, 2 lines and 3 lines-to-ground fault of matrix-type SFCLs (MFCLs) and the electromagnetic field distribution of reactors for MFCLs under the same cases of ground faults. To do this, we fabricated MFCLs with 6 reactors for 3 phases. Each reactor had the length of 270 mm and diameter of 80 mm. 6 reactors were made by Bakelite. We reported experimental results, including fault currents, fault voltages and magnetic field distribution according to phase differences between each phase. We confirmed that experimental results will be useful in next future plan for real power grid.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2008.06a
• /
• pp.289-289
• /
• 2008

We investigated the operational characteristics of the separated three-phase flux-lock type superconducting fault current limiter (SFCL). The single-phase lock type SFCL consist of two coils, which are wound in parallel through an iron core. The high-$T_c$ superconducting(HSTC) thin film connected in series with secondary coil. The separated three-phase flux-lock type SFCL consist of three single-phase flux-lock type SFCL. In a normal condition, the SFCL is not operate. When a fault occurs, the current of a HSTC thin film exceeds its critical current by fault current, the resistance of the HSTC thin film generated. Therefore fault current was limited by SFCL. The separated three-phase flux-lock type SFCL are operated in fault condition such as the the single line-to-ground fault, the double line-to-ground fault and the triple line-to-ground fault. The experimental results, the SFCL operational characteristics was dependent on fault condition.

• Proceedings of the KIEE Conference
• /
• 2007.07a
• /
• pp.736-737
• /
• 2007

The single point bonding in underground transmission system can induce high voltage on the sheath when ground fault, lightning serge and switching serge occurs, at that time underground cable systems cannot offer a return path of fault current. Accordingly if fault current, which cannot return to ground, flows at the single point bonding, high voltage can be induced in SVL and that voltage can cause aging and breakdown of SVL. Therefore this paper study on the effect of parallel ground conductor at the single point bonding when ground fault and lightning serge occurs by using ATPDraw.