Vibration Analysis and Evaluation of the Indoor Spiral Steel Stair

The spiral steel stair is widespread used as indoor stair for its graceful appearance. For the space structure system of the spiral stair, it is necessary to make vibration analysis and comfort evaluation to the stair. The load model of pedestrian and the analysis condition by walking and running in the process of ascending and descending are presented in this paper. Referring to some design code and research achievement of footbridge and floor, the index of comfort evaluation, which are the natural frequency, the peak vertical acceleration and the weighted root-mean-square (r.m.s) acceleration, are put forward in this paper. Finally, the numerical analysis and the vibration site test of a practical project are made and the results of vibration analysis and comfortability evaluation are presented to demonstrate the suggestion by the authors.

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Field measurement-based pedestrian-induced vibration analysis and comfort evaluation of a steel truss footbridge

JOURNAL OF SHENZHEN UNIVERSITY SCIENCE AND ENGINEERING ◽

10.3724/sp.j.1249.2015.01089 ◽

2015 ◽

Vol 32 (1) ◽

pp. 89

Author(s):

Qiang Li ◽

Meidi Shan ◽

Mingfeng Huang ◽

Ju Chen ◽

He Feng

Keyword(s):

Field Measurement ◽

Vibration Analysis ◽

Comfort Evaluation ◽

Steel Truss

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A Vibration Analysis and Evaluation System Construction Based on On-Line Inspection

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.605-607.1164 ◽

2012 ◽

Vol 605-607 ◽

pp. 1164-1167

Author(s):

Yan Chun Xia

Keyword(s):

Vibration Analysis ◽

Evaluation System ◽

Good Method ◽

Assessment System ◽

System Construction ◽

Total Risk ◽

Assessment Index ◽

Important Method ◽

Analysis And Evaluation ◽

On Line

Vibration analysis(VA) is a very important method in the industry inspection application. Based on ISO10816, the severity level, certainty rating, the total risk rating matrix and the risk assessment index were proposed in the paper. Based on the testing samplings in a certain company and the assessment system established above, the VA analysis can be conducted and it is a good method for applying the predictive maintenance in the plant.

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Vibration Analysis and Evaluation of Piezoelectric Micromachined Ultrasonic Transducers Using Epitaxial Pb(Zr, Ti)O3 Thin Film

Sensors and Materials ◽

10.18494/sam.2015.1040 ◽

2015 ◽

Cited By ~ 1

Keyword(s):

Thin Film ◽

Vibration Analysis ◽

Ultrasonic Transducers ◽

Analysis And Evaluation

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Study on Flow Induced Vibration Analysis and Evaluation for Heat Transfer Tube of Steam Generator

Volume 4: Fluid-Structure Interaction ◽

10.1115/pvp2018-84587 ◽

2018 ◽

Author(s):

Xuan Huang ◽

Huan-Huan Qi ◽

Feng-Chun Cai ◽

Zhi-Peng Feng ◽

Shuai Liu

Keyword(s):

Heat Transfer ◽

Steam Generator ◽

Vibration Analysis ◽

Two Phase Flow ◽

Phase Flow ◽

Flow Induced Vibration ◽

Two Phase ◽

Heat Transfer Tube ◽

Analysis And Evaluation ◽

Transfer Tube

The heat transfer tube of steam generator is an important part of the primary loop boundary, the integrity is crucial to the safe operation of the whole reactor system; the flow induced vibration is one of the main factors leading to the failure of heat transfer tube in steam generator. Both ASME and RG1.20 have made a clear requirement for the analysis and evaluation of the flow induced vibration of steam generator. The flow induced vibration of heat transfer tube in two-phase flow is the difficult and important content in the analysis. In this paper, the finite element model of heat transfer tube is established and the modal analysis is carried out. Then in order to evaluate the influence of two-phase flow in the secondary side and support boundary constraint, the analytical results are compared with the natural frequencies of the heat transfer tube measured in the two-phase flow test. On the basis of accurate simulation of the dynamic characteristics of heat transfer tube in two-phase flow, the paper calculate the turbulent excitation response and the fluidelastic instability ratio aiming at the main mechanism causing the flow induced vibration of heat transfer tube in two-phase flow. Firstly, the modified PSD of turbulent excitation is proposed on the foundation of root mean square displacement amplitude of heat transfer tube measured in two-phase flow test. The calculation result of the amplitude of heat transfer tube with different void fraction can envelope the test result by using the modified PSD as input, and the safety margin is reasonable. Then we also verify whether the analysis conclusion of fluidelastic instability is in agreement with the test. Finally, the analytical technique is applied to the analysis of flow induced vibration of steam generator to verify the design of structure. The paper studies on flow induced vibration analysis and evaluation a heat transfer tube of steam generator in two-phase flow. The analysis program of flow induced vibration on the basis of the test results. The investigation can be used for the risk prediction and evaluation of flow induced vibration of heat transfer tube in two-phase flow, solve the technical difficulties of flow induced vibration analysis in two-phase flow, and provide the technical support for the flow induced vibration analysis of steam generator.

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Measurement and Prediction of the Pedestrian-Induced Vibrations of a Footbridge

Noise & Vibration Worldwide ◽

10.1260/095745609788251581 ◽

2009 ◽

Vol 40 (4) ◽

pp. 10-19

Author(s):

P. Van den Broeck ◽

G. De Roeck ◽

E. Reynders ◽

D. Degrauwe ◽

I. Bojidarova Georgieva ◽

...

Keyword(s):

Prediction Method ◽

Element Model ◽

Vertical Acceleration ◽

Load Model ◽

Acceleration Level ◽

Numerical Predictions ◽

Vibration Serviceability ◽

Increasing Trend ◽

Series Of Experiments ◽

Vertical Accelerations

Vibration serviceability has become an important issue in the design of modern slender footbridges with large spans. This paper presents the measurements and the numerical predictions of the footfall-induced vibrations of a pedestrian bridge. A series of experiments were carried out with different-sized groups crossing the bridge, varying in number from 10 up to 50 participants and recording the vertical and lateral accelerations at different locations on the bridge. Two types of tests were performed: free walking and synchronized walking by means of a metronome signal, recorded on a tape recorder carried by the group of students. The effect of the test type is analyzed and shows a magnitude in difference between the vertical accelerations caused by the free and the synchronized walking. The increasing trend of the acceleration levels with increasing group size is also clearly observed. A numerical prediction method is used to simulate the synchronized walking experiments based on an updated finite element model of the bridge and a single pedestrian load model. It is shown that the predicted acceleration level is sensitive to the assumptions made regarding the level of synchronization between the pedestrians and the magnitude of the dynamic load generated by each pedestrian. Taking into account these specific measurement conditions, a fair agreement is obtained between the predicted and the observed vertical acceleration levels at seven positions along the length of the footbridge.

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Vibration Analysis and Evaluation for the Offshore Structure Using Simplified Model and RSS Method

Volume 2: Structures, Safety and Reliability ◽

10.1115/omae2012-84053 ◽

2012 ◽

Author(s):

Chan Hui Lee ◽

Keun Bok Song ◽

Heui Won Kim

Keyword(s):

Vibration Analysis ◽

Mesh Size ◽

Summation Method ◽

Vibration Characteristics ◽

Simplified Model ◽

Design Stage ◽

Analysis Method ◽

Offshore Structure ◽

Analysis And Evaluation ◽

Forced Vibration Analysis

The evaluation of the vibration characteristics of offshore structure in the design stage is important to ensure the safety of structure, equipment and worker. Conventionally, the vibration analysis of the offshore structure is carried out according to its own analysis procedure including the selection of vibrating equipment, FE modeling, evaluation of excitation forces and criteria. The efficient modeling of the vibration equipment and the consideration of the phase of excitation forces are necessary to reduce the calculation time and to increase the accuracy of analysis. In this paper, the efficient and accurate vibration analysis method is introduced including the simplified model of equipment and the RSS (root squared summation) method. The vibration equipment was modeled as the simplified model of which mesh size is reduced by 90%, however, its vibration characteristics such as natural frequency and vibration modes are not changed. In addition, the RSS method was applied in the forced vibration analysis to consider appropriate phase of excitation forces. As the RSS method is the summation of all the vibration response with respect to each excitation forces, it presents more reasonable and conservative vibration evaluation. The proposed vibration analysis method has been confirmed by conducting various offshore projects and is expected to be more efficient for the design of offshore structure.

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