Ambient vibration monitoring [[electronic resource] /] / Helmut Wenzel, Dieter Pichler

• Record Nr.: UNINA9910830936203321
• Autore: Wenzel Helmut
• Pubbl/distr/stampa: Chichester, England, : John Wiley, 2005
• ISBN: 1-280-28756-X; 9786610287567; 0-470-02457-7; 0-470-02431-3
• Descrizione fisica: 1 online resource (309 p.)
• Altri autori (Persone): PichlerDieter
• Disciplina: 620.3; 624.2/52; 624.252
• Soggetti: Bridges - Vibration
• Lingua di pubblicazione: Inglese
• Formato: Materiale a stampa
• Livello bibliografico: Monografia
• Note generali: Description based upon print version of record.
• Nota di bibliografia: Includes bibliographical references and index.
• Nota di contenuto: AMBIENT VIBRATION MONITORING; Contents; PREFACE; ACKNOWLEDGEMENTS; SUMMARY; 1 INTRODUCTION; 1.1 Scope of Applications; 1.2 Laws and Regulations; 1.3 Theories on the Development of the AVM; 2 OBJECTIVES OF APPLICATIONS; 2.1 System Identification; 2.1.1 Eigenfrequencies and Mode Shapes; 2.1.2 Damping; 2.1.3 Deformations and Displacements; 2.1.4 Vibration Intensity; 2.1.5 Trend Cards; 2.2 Stress Test; 2.2.1 Determination of Static and Dynamic Stresses; 2.2.2 Determination of the Vibration Elements; 2.2.3 Stress of Individual Structural Members; 2.2.4 Determination of Forces in Tendons and Cables; 2.3 Assessment of Stresses2.3.1 Structural Safety; 2.3.2 Structural Member Safety; 2.3.3 Maintenance Requirements and Intervals; 2.3.4 Remaining Operational Lifetime; 2.4 Load Observation (Determination of External Influences); 2.4.1 Load Collective; 2.4.2 Stress Characteristic; 2.4.3 Verification of Load Models; 2.4.4 Determination of Environmental Influences; 2.4.5 Determination of Specific Measures; 2.4.6 Check on the Success of Rehabilitation Measures; 2.4.7 Dynamic Effects on Cables and Tendons; 2.4.8 Parametric Excitation; 2.5 ; Monitoring of the Condition of Structures; 2.5.1 Assessment of Individual Objects2.5.2 Periodic Monitoring; 2.5.3 BRIMOS® Recorder; 2.5.4 Permanent Monitoring; 2.5.5 Subsequent Measures; 2.6 Application of Ambient Vibration Testing to Structures for Railways; 2.6.1 Sleepers; 2.6.2 Noise and Vibration Problems; 2.7 Limitations; 2.7.1 Limits of Measuring Technology; 2.7.2 Limits of Application; 2.7.3 Limits of Analysis; 2.7.4 Perspectives; References; 3 FEEDBACK FROM MONITORING TO BRIDGE DESIGN; 3.1 Economic Background; 3.2 Lessons Learned; 3.2.1 Conservative Design; 3.2.2 External versus Internal Pre-stressing; 3.2.3 Influence of Temperature3.2.4 Displacement; 3.2.5 Large Bridges versus Small Bridges; 3.2.6 Vibration Intensities; 3.2.7 Damping Values of New Composite Bridges; 3.2.8 Value of Patterns; 3.2.9 Understanding of Behaviour; 3.2.10 Dynamic Factors; References; 4 PRACTICAL MEASURING METHODS; 4.1 Execution of Measuring; 4.1.1 Test Planning; 4.1.2 Levelling of the Sensors; 4.1.3 Measuring the Structure; 4.2 Dynamic Analysis; 4.2.1 Calculation Models; 4.2.2 State of the Art; 4.3 Measuring System; 4.3.1 BRIMOS®; 4.3.2 Sensors; 4.3.3 Data-Logger; 4.3.4 Additional Measuring Devices and Methods; 4.4 Environmental Influence4.5 Calibration and Reliability; 4.6 Remaining Operational Lifetime; 4.6.1 Rainflow Algorithm; 4.6.2 Calculation of Stresses by FEM; 4.6.3 S-N Approach and Damage Accumulation; 4.6.4 Remaining Service Lifetime by Means of Existing Traffic Data and Additional Forward and Backward Extrapolation; 4.6.5 Conclusions and Future Work; References; 5 PRACTICAL EVALUATION METHODS; 5.1 Plausibility of Raw Data; 5.2 AVM Analysis; 5.2.1 Recording; 5.2.2 Data Reduction; 5.2.3 Data Selection; 5.2.4 Frequency Analysis, ANPSD (Averaged Normalized Power Spectral Density); 5.2.5 Mode Shapes
• Sommario/riassunto: In-operation vibration monitoring for complex mechanical structures and rotating machines is of key importance in many industrial areas such as aeronautics (wings and other structures subject to strength), automobile (gearbox mounting with a sports car body), rail transportation, power engineering (rotating machines, core and pipes of nuclear power plants), and civil engineering (large buildings subject to hurricanes or earthquakes, bridges, dams, offshore structures). Tools for the detection and the diagnosis of small changes in vibratory characteristics are particularly useful to set up a pr