• Title/Summary/Keyword: serviceability

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A Study on Vibration Serviceability Evaluation of Continuous Slab Bridges (연속슬래브교의 진동사용성 평가에 관한 연구)

  • Kim, Kee-Dae
    • Journal of the Korean Society of Industry Convergence
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    • v.9 no.3
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    • pp.199-206
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    • 2006
  • Extraordinary displacement and vibration by heavy vehicle causes passengers to feel mental uncomfortableness and bridge to be damaged. To increase serviceability, the research on the human influence for vibration to happen at the bridge has been performed for a long time in oversea but it does not draw concern relatively in the domestic. The purpose of this research is to develop an evaluation method for vibration serviceability of continuous slab bridge. This research is focused on establishing theoretical method to assess vibration serviceability of bridge considering natural frequency, displacement, and acceleration since the criteria for the human responses to vibration is generally based on frequency band. By examining the characteristics of vibration serviceability which has been assessed with human response curve through field experiments as well as analytical study, the evaluation method of vibration serviceability for continuous slab bridges is proposed. Based on applications to the example of continuous slab bridge, the simple evaluation of vibration serviceability in the paper may be used in the initial step of design practice.

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Evaluation of Serviceability due to Vibration of Slab (건축구조물의 슬래브 진동에 의한 사용성 평가 연구)

  • 우운택
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2000.10a
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    • pp.245-250
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    • 2000
  • Recent building structures are superior in its ability but they are light and fiexible, and so have problems of vibration. In general, the serviceability of RC slabs was known to be good against vibration because of its hardness. However recent high-rise apartment slabs are mostly light and long, the serviceability about vibration problems of RC slabs was performed. Basic information and its influence on vibrations of RC slabs were revealed. Also, its serviceability against vibration was examined. Many tests were conducted on existing building located in Chung-Nam area. As a results, damping ratio, natural frequency, acceleration amplitude and displacement amplitude which were used to examine serviceability of the RC slabs were obtained. These results on the test building proved that its serviceability conditions were satified to meet the code against vibration.

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Evaluation of Serviceability due to Vibration of Slab (건축구조물의 슬래브 진동에 의한 사용성 평가 연구)

  • Woo, Woon-Taek;Park, Tae-Won;Chung, Lan
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.4 no.4
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    • pp.225-230
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    • 2000
  • Recent building structures are superior in its ability but they are light and flexible, and so have problems of vibration. In general, the serviceability of RC slabs was known to be good against vibration because of its hardness. However, recent high-rise apartment slabs are mostly light and long, the serviceability of RC slabs due to vibration could be a problem. In this paper, a basic investigation about vibration problems of RC slabs was performed. Basic information and its influence on vibrations of RC slabs were revealed. Also, its serviceability against vibration was examined. Many tests were conducted on existing building located in Chung-Nam area. As a results, damping ratio, natural frequency, acceleration amplitude and displacement amplitude which were used to examine serviceability of the RC slabs were obtained. These results on the test building proved that its serviceability conditions were satisfied to meet the code against vibration.

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Estimation of Stiffness Limit for Railway Bridge Vibration Serviceability (진동사용성을 고려한 철도교량구조물의 강성한계 분석)

  • Park, Kyung-Rock;Jeon, Bub-Gyu;Kim, Nam-Sik;Kim, Sung-Il
    • Proceedings of the KSR Conference
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    • 2008.06a
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    • pp.80-85
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    • 2008
  • In general, deflection limit criteria of bridge design specifications have been considered based on static serviceability and structural stability. Dynamic serviceability induced from bridge vibration actually has not been included in the criteria. Thus, it is necessary for comfort limit to be considered in order to check dynamic serviceability on bridge vibration. In this study, the comfort limit of bridge structures based on the RMQ and VDV considering the signal fluctuation effectively and the time duration exposed has been constructed. The comfort limit developed in time domain was verified by using vibration signals directly measured from the existing bridges. Comparing the developed comfort limit with the conventional ones defined in frequency domain, it is shown that the comfort limit developed in time domain would be more feasible for evaluating quantitatively the serviceability due to bridge vibration. Using the Bridge-train interaction analysis program, dynamic response of the bridge by the stiffness change were obtained for several railway bridges. And, a stiffness limit satisfying the bridge vibration serviceability was estimated by compared with comport limit. From the results, a new deflection limit on bridge structures satisfying the vibration serviceability could be proposed by comparing with the conventional deflection limit criteria.

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Serviceability-oriented analytical design of isolated liquid damper for the wind-induced vibration control of high-rise buildings

  • Zhipeng Zhao;Xiuyan Hu;Cong Liao;Na Hong;Yuanchen Tang
    • Smart Structures and Systems
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    • v.33 no.1
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    • pp.27-39
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    • 2024
  • The effectiveness of conventional tuned liquid dampers (TLDs) in controlling the wind-induced response of tall flexible structures has been indicated. However, the impaired control effect in the detuning condition or a considerably high mass cost of liquid may be incurred in ensuring the high-level serviceability. To provide an efficient TLD-based solution for wind-induced vibration control, this study proposes a serviceability-oriented optimal design method for isolated TLDs (ILDs) and derives analytical design formulae. The ILD is implemented by mounting the TLD on the linear isolators. Stochastic response analysis is performed for the ILD-equipped structure subjected to stochastic wind and white noise, and the results are considered to derive the closed-form responses. Correspondingly, an extensive parametric analysis is conducted to clarify a serviceability-oriented optimal design framework by incorporating the comfort demand. The obtained results show that the high-level serviceability demand can be satisfied by the ILD based on the proposed optimal design framework. Analytical design formulae can be preliminarily adopted to ensure the target serviceability demand while enhancing the structural displacement performance to increase the safety level. Compared with conventional TLD systems, the ILD exhibits higher effectiveness and a larger frequency bandwidth for wind-induced vibration control at a small mass ratio.

Design of Reinforced Concrete Members for Serviceability Based on Utility Theory

  • Lee, Young Hak;Kim, Sang Bum
    • Architectural research
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    • v.7 no.2
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    • pp.61-68
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    • 2005
  • A methodology for design of reinforced concrete members for serviceability in general and deflection control in particular is presented based on application of utility theory. The approach is based on minimizing total cost including both initial construction and cost of failure considering variability in structural behavior and various forms of serviceability loss function. The method is demonstrated for the case of a simply supported slab for example.

Evaluation of Comfort Limit on Bridge Vibration (교량구조물의 진동 사용성 분석)

  • Kim, Nam-Sik;Jeon, Bub-Gyu
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2007.05a
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    • pp.161-170
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    • 2007
  • In general, deflection limit criteria of bridge design specifications would have been considered based on the static serviceability and structural stability. Dynamic serviceability induced from bridge vibration, as a comfort limit, actually has not been included in the criteria. Thus, it is necessary for dynamic serviceability to be considered in bridge vibration problems and for comfort limit on vibration to be needed for evaluating dynamic serviceability of bridges. In this paper, comfort limits of bridge structures considering the time duration exposed by vibration were examined with frequency and time dependent comfort limits, and they were evaluated by using the vibration signals measured from the existing bridges. Therefore, it is resulted that the time-dependent comfort limit considering the duration of vibration is an efficient estimate for evaluating dynamic serviceability of bridges.

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Evaluation of Comfort Limit on Bridge Vibration (교량구조물의 진동 사용성 분석)

  • Jeon, Bub-Gyu;Kim, Nam-Sik
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.17 no.10
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    • pp.923-935
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    • 2007
  • In general, deflection limit criteria of bridge design specifications would have been considered based on the static serviceability and structural stability. Dynamic serviceability induced from bridge vibration, as a comfort limit, actually has not been included in the criteria. Thus, it is necessary for dynamic serviceability to be considered in bridge vibration problems and for comfort limit on vibration to be needed for evaluating dynamic serviceability of bridges. In this paper, comfort limits of bridge structures considering the time duration exposed by vibration were examined with frequency and time dependent comfort limits, and they were evaluated by using the vibration signals measured from the existing bridges. Therefore, it is resulted that the time-dependent comfort limit considering the duration of vibration is an efficient estimate for evaluating dynamic serviceability of bridges.

Serviceability Evaluation of Sky Bridge With Isolation Device (면진장치 장착 스카이 브릿지의 사용성 평가)

  • Kim, Gee-Cheol;Kim, Hyun-Su;Kim, Su-Geun
    • Journal of Korean Association for Spatial Structures
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    • v.17 no.2
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    • pp.71-77
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    • 2017
  • In this study, the boundary non-linear analysis of the sky bridge subjected to walking load and running load is performed. The sky bridge is installed in the mid-story between two buildings and the walking load and running load induced by pedestrians are measured by load cell. LRB is modeled as a non-linear hysteresis model to accurately represent the behavior of LRB. For the serviceability evaluation of sky bridge, the acceleration responses of sky bridge are analyzed based on ISO 2631-2 and the velocity response are analyzed based on standards Bachmann &Amann. In serviceability evaluation of this sky bridge, the pedestrian can not perceive the vibration except for resonance running loads consequently. Therefore, it is concluded that this sky bridge haven't problem in the serviceability.

Probability of exceeding the serviceability limit of antenna masts

  • Kammel, Christian
    • Wind and Structures
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    • v.4 no.4
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    • pp.353-366
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    • 2001
  • With respect to serviceability, antenna masts should be designed so that wind-induced motion will not cause unacceptable lack of transmission for broadcasting users and wireless communication. For such antenna masts with directional radio transmission the serviceability limit state is predominantly governed by the tolerable change of the broadcasting angle of the mounted antenna assembly and therefore by the tip distortion of the mast. In this paper it will be shown that refinements of the present state of design of antenna masts are possible by using the statistics of extremes applied to extreme wind situations and by consideration of the statistical and reliability requirements given by the operator such as frequency and return period of passing the serviceability limit.