• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.5
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• pp.3557-3566
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• 2015

In the case of elevated railway station in which railway is connected with superstructure of station, vibration and noise level is relatively higher than those of general structure type station due to structural characteristic which transmits vibration directly. Therefore, characteristic understanding of structural vibration and accompanying structure cause noise and establishment of reduction plan through the results are in need. Test and analysis are performed in this research to consider correlativity between structural vibration and accompanying structure cause noise when external forces are applied on standard slab and floating slab which is able to isolate vibration. By producing and loading on standard and floating slab, vibration and noise response are measured while simulation using numerical analysis, finite element method and SEA method is performed. The results about structural dynamic behavior of slab, correlativity between structural vibration and noise, reduction performance of floating slab is deduced through the analysis of tests.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.37 no.4
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• pp.243-250
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• 2024

Recently, accidents involving structural elements, formwork, and shore have occurred continuously during concrete pouring, especially in multistory-shored RC structure systems with non-typical stories with increased slab thicknesses. In previous studies, an analysis was conducted on the stiffness of concrete and distribution of slab construction loads when some slab thicknesses were increased under the same conditions. This study analyzed the construction load, construction damage parameter, and shoring force by varying the construction conditions, such as the construction period and number of shores, as well as the design conditions, such as the thickness increment and number of thickness increment slabs, in a multistory-shored RC structure system with non-typical stories with increased slab thickness.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2000.11a
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• pp.87-90
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• 2000

In this paper. we present a method for a systematic design of a dielectric slab polarizer in the circular waveguide. This structure is realized using a tapered dielectric slab inside a circular waveguide. Commercial software is used to obtain the equivalent dielectric constant of the circular waveguide partially filled with a dielectric slab. The length of the tapered region is determined so that the reflection from the dielectric slab is sufficiently low. A polarizer operating at 10 GHz band is designed, fabricated and tested.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.2
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• pp.90-98
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• 2014

The shear behavior of reinforced concrete structure is one of difficult problems that are not clearly identified theoretically despite the efforts of researchers for several years. Since bending and shear strength of hollow slab may decrease due to hollow part inside slab, prediction of such structure performance is very important. Presently the formulas of shear designing standard expressions of each country are formulas by experiment for hollow slab. In this study, the shear behavior of one-way hollow slab by reinforcement ratio were analyzed through experiment to conduct studying on estimation of shear strength, and then shear strength formulas of hollow slab were compared and analyzed.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.1659-1663
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• 2011

Precast concrete slab track is a track structure to be installed by transporting and assembling precast concrete slabs manufactured at the factory. This method can improve concrete quality, provide easy maintenance and reduce construction time, compared with in-situ concrete track. However, the concrete slabs being continuously connected in longitudinal direction, due to the temperature change between summer and winter, the openings at slab joints have occurred. Thus, in this study, to identify the cause of this opening of slab joint, the joint opening caused by temperature drop in the longitudinally continuous precast concrete slab track has been predicted using three-dimensional finite element analysis, and compared with field measurements. Based on the proven model, the slab joint opening, and the stress pattern of concrete slab and steel reinforcement according to concrete slab-base friction properties, concrete-reinforcement bond properties, and prestressing were analyzed.

• Journal of Korean Association for Spatial Structures
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• v.12 no.3
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• pp.89-95
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• 2012

Post-tensioned void slab is frequently used for improving the deflection and sound proofing. Two one story 8m spanned structures were built. One structure applied post-tensioned solid slab, but the other did post-tensioned void slab. Dynamic characteristics, which is natural frequency and damping ratio, was compared between that of solid slab and void slab before and after post tension. The natural frequency of void slab was greater than that of solid slab before and after post tension. It was shown that damping ratio of solid slab and void slab was almost same at two stages.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.05a
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• pp.513-517
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• 2004

This study aims to evaluate factors of floor structure influencing to the floor impact sound. For this reasons, we measured the vibration of floor and the floor impact sound in moment flame structure. The main results from this study are that slab area and thickness are critical factors of the floor impact sound and aspect ratio slab is not verified in flor impact sound.

• Journal of the Korean Society of Hazard Mitigation
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• v.7 no.5
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• pp.99-110
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• 2007

A single slab concrete pavement has been modeled and analyzed by ABAQUS program. The stress and displacement of the JCP slab under traffic load with frictionless contact interaction between slab and base calculated by ABAQUS program have been compared with the results obtained by KENSLABS program. The results of the stresses of the two modeling show similar tendency and the difference of the two modeling is very small however the results of the displacement of the two modeling show some dissimilarity. In order to analyze the effects of material and geometric properties on the responses of slab, some varying parameters were chosen as input for the modeling. The changing parameters include the thickness and elastic modulus of the concrete slab, the thickness and elastic modulus of base and the elastic modulus of the subgrade. The contact interaction between the slab and base layer had been also studied and different friction coefficient 0, 2.5, 6.6, 7.5, 8.9 had been used to simulate the different friction interface condition. The results of the analysis showed that the responses of the concrete slab vary with the material and geometric properties of the pavement structure and the slab-base friction condition.

• Steel and Composite Structures
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• v.25 no.5
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• pp.523-534
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• 2017

Cable-supported ribbed beam composite slab structure (CBS) is proposed in this study. As a new cable-supported structure, it has many merits such as long span availability and cost-saving. Inspired by the previous research on cable-supported structures, the fabrication and construction process are developed. Pre-stress design method based on static equilibrium analysis is presented. In the algorithm, the iteration convergence can be accelerated and the calculation result can be kept in an acceptable precision by setting a rational threshold value. The accuracy of this method is also verified by experimental study on a 1:5 scaled model. Further, important parameters affecting the mechanical features of the CBS are discussed. The results indicate that the increases of sag-span ratio, depth of the ribbed beam and cable diameter can improve the mechanical behavior of the CBS by some extent, but the influence of strut sections on mechanical behavior of the CBS is negligible.

• Fire Science and Engineering
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• v.25 no.6
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• pp.64-72
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• 2011

The concrete void slab structure with the existing mushroom slab, is the structure that maximizes the advantages, while minimizing the weakness with removing useless body force of the concrete part, located on the center of the slab cross-section, which does not need to support the structural weight. In this research, a fire test is performed to analyze how the blaze behave according to the thickness of slab cover, with the practical span length of concrete void slab for the slab length 7.5 m. With this heating test, we assumed the uniform-load-model considering fixed loads and live loads, and chose the standard fire test condition. We measured the temperature changes and the deflection character according to the depth from the heat exposure side, and assessed the resisting capability according to the standard KS F 2257-1. The result comes out with the EPS model can secure about 2 hour fire-resisting-capability with 50 mm of cover depth.