• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.659-662
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• 2003

Recently, the floor thickness in residence may not be satisfied with the floor vibration criteria although the thickness is evaluated by the serviceability requirements in current design provisions. Thus it is necessary to develop the procedure to determine slab thickness satisfied with the floor vibration criteria. In this study, We proposed the methods to determine the slab thickness satisfied with the vertical floor vibration criteria for several concrete compressive strength of flat plate floor systems. For this purpose Monte Carlo simulation procedure was adopted and both randomness inherent in young modulus of concrete and heel drop intensity were accounted.

• Steel and Composite Structures
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• v.46 no.4
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• pp.577-589
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• 2023

In this study, on-site testing was carried out to investigate the vibration performance of a cold-formed thin-walled steel floor system. Ambient vibration, walking excitation (single and double persons), and impulsive excitation (heel-drop and jumping) were considered to capture the primary vibration parameters (natural frequencies, damping ratios, and mode shapes) and vertical acceleration response. Meanwhile, to discuss the influence of cement fiberboard on structural vibration, the primary vibration parameters were compared between the systems with and without the installation of cement fiberboard. Based on the experimental analysis, the cold-formed thin-walled steel floor possesses high frequency (> 10 Hz) and damping (> 2%); the installed cement fiberboard mainly increases the mass of floor system without effectively increasing the floor stiffness and may reduce the effects of primary vibration parameters on acceleration response; and the human-structure interaction should be considered when analyzing the vibration serviceability. The comparison of the experimental results with those in the AISC Design Guide indicates that the cold-formed thin-walled steel floor exhibits acceptable vibration serviceability. A crest factor 𝛽_rp (ratio of peak to root-mean-square accelerations) is proposed to determine the root-mean-square acceleration for convenience.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.305-309
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• 2006

In this paper vibration reduction characteristics of floating floors used in railway vehicles are studied. Vibration reduction characteristics are compared through a series of tests for elastically-coupled floor and rigidly-coupled floor. It was found that elastically-coupled floor has larger vibration reduction amount than rigidly-coupled floor. Around the fundamental natural frequency, however, elastic floor has poor vibration reduction effect than rigid floor. Measures to reduce structure-borne noise are also discussed based on the test results. Structure-borne noise for running railway vehicles cannot be reduced by an effort to deviate resonance between natural frequency of floors and major exciting forces. Instead, reducing vibration level of top floor and using covers which have low sound radiation coefficient will be effective for reducing structure-borne noise.

• Proceeding of KASS Symposium
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• 2006.05a
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• pp.246-255
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• 2006

In these days the floor vibration is beginning to make its appearance of the environmental dispute in apartment building. Standard floor system are suggested for the settlement of this issue by government. The sound of floor impact sound is needed to secure comfortable quality in housing. Also, it is required an accurate analysis and a proper evaluation for floor vibration. Refine model is necessary for the floor system of housing to analyze accurately the floor vibration. But this refine model is not efficient because it is required so much running time for vibration analysis and it is difficult of modeling of standard floor slab. In this paper, new modeling methods of standard floor slab are proposed for the accurate rigidity evaluation. By using the new modeling method, the accurate vibration response can be obtained and can accurately evaluate the rigidity of standard floor system with resilient materials. Therefore the proposed modeling method is of practical use for vibration analysis of floor system of apartment building.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.1459-1462
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• 2007

In this study, vibration characteristics of concrete slab were investigated through FEM analysis. Four different floor plans with the floor area of $100{\sim}130m^2$ were chosen to be analyzed. Boundary conditions of two dimensional finite element models were determined based on the modal test results. Results showed that mode shapes were formed somewhat different according to the floor plan and the contribution of 1st mode on the floor vibration is generally the highest. Through the transient analysis, it was also found that floor plan, expecially connection of the living room with the kitchen, affected the vibration acceleration levels.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.16 no.6 s.111
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• pp.574-581
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• 2006

Flat plate slab systems are more economical rather than reinforced concrete frame systems because flat plate slab system reduces story height. Furthermore flat plate systems are more popularly needed in construction practice due to flexibility of plan. Korean Concrete Provisions 2003 provide the minimum thickness of the slab that satisfies serviceability requirement to the static displacement. However, floor thickness in residence buildings may not satisfy the floor vibration criteria although the thickness satisfies the serviceability requirements in current design provisions. This study estimates the dynamic properties of floor vibration for existing flat plate slabs, and proposes the slab thickness satisfying the floor vibration criteria. The dynamic response analysis using finite element method and reliability analysis are carried out for this Purpose.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1999.04a
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• pp.127-134
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• 1999

Vibration problem occurring at the metal deck floor system not only reduces the serviceability of a building but also reduces the usability of a floor system. Most problem occurring at the metal deck floor results from the human movement such as walking and running. However the vibration induced by running does not occur continuously except the special case. therefore the floor vibration due to walking was only considered on this paper,. Vibration occurring due to human walking was measured and the corresponding load function was derived through the Fast Fourier Transform(FFT)

• Journal of the Computational Structural Engineering Institute of Korea
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• v.18 no.1
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• pp.61-69
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• 2005

As long-span and light-weight deck floor slab are flexible and have low inherent damping, the significant floor vibration could be induced by residents' activities. These floor vibrations affect to safety and serviceability of building structures. So the vibration criteria are applied to the quality assessment of building structure. Therefore, the accurate vibration analysis should be performed for the correct assessment of deck floor slab. In this paper, practical analysis method with considering orthotropic rigidity of deck floor is proposed tot the accurate vibration analysis of dock floor slabs with form deck plates.

• Steel and Composite Structures
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• v.30 no.6
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• pp.577-589
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• 2019

In this study, on-site testing was carried out to investigate the vibration performance of a composite steel-bar truss slab with steel girder system. Ambient vibration was performed to capture the primary vibration parameters (natural frequencies, damping ratios, and mode shapes). The composite floor possesses low frequency (< 10 Hz) and damping (< 2%). Based on experimental, theoretical, and numerical analyses on natural frequencies and mode shapes, the boundary condition of SCSC (i.e., two opposite edges simply-supported and the other two edges clamped) is deemed more reasonable for the composite floor. Walking excitations by one person (single excitation), two persons (dual excitation), and three persons (triple excitation) were considered to evaluate the vibration serviceability of the composite floor. The measured acceleration results show a satisfactory vibration perceptibility. For design convenience and safety, a crest factor ${\beta}_{rp}$ describing the ratio of peak acceleration to root-mean-square acceleration induced from the walking excitations is proposed. The comparisons of the modal parameters determined by ambient vibration and walking tests reveal the interaction effect between the human excitation and the composite floor.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.10a
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• pp.225-226
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• 2014

In multi-story buildings, heavy-weight floor impact noise propagates through multiple layers. In order to evaluate the influence of structural vibration and propagation, the actual twelve-story building was excited by an impact ball. Sound and vibration responses of each floor was measured using accelerometers and a microphone. Vibration characteristics and its transfer paths were different depending on the excitation floor locations due to differences in the structural characteristics. From the measurement result, transfer characteristics were quantified by statistical energy analysis. It was confirmed that the heavy-weight floor impact noise influence not only adjacent floor. The impact noise transferred and affected multiple layers.