Ambient Vibration Monitoring

by Wenzel, Helmut; Pichler, Dieter

• ISBN13: 9780470024300
• ISBN10: 0470024305
• Edition: 1st
• Format: Hardcover
• Copyright: 2005-05-27
• Publisher: WILEY

Summary

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 preventive maintenance policy based on the actual evolution of the state of the monitored machine or structure, as opposed to systematic a priori planning. Ambient Vibration Monitoring is the backbone of such structural assessment monitoring and control. It provides the possibility to gain useful data under ambient conditions for the assessment of structures and components. Written by a widely respected authority in this area, Ambient Vibration Monitoring describes the current practice of ambient vibration methodologies illustrated by a number of practical examples. Designed to aid the practical engineer with their understanding of the topic, it is the culmination of many years of practical research and includes numerous 'real world' examples. It also provides information on applicable solutions. This book will enable not only practitioners (in civil, mechanical and aerospace engineering), but also researchers and students, to learn more about the theory and practical applications of this subject.

Author Biography

Dr Helmut Wenzel, Managing Director

Dieter Pichler, both of VCE Holding GmbH, Vienna, Austria

Table of Contents

Summary.

1.         Introduction.

1.1         Scopes of Application.

1.2         Laws and Regulations.

1.3         Theories on the Development of AVM.

2.          Objectives of Applications.

2.1         System Identification.

2.2         Stress Test.

2.3         Assessment of Stresses.

2.5         Monitoring of the Condition of Structures.

2.6         Application of Ambient Vibration Testing to Structures for Railways.

2.7         Limitations.

References.

3          Feedback from Monitoring to Bridge Design.

3.1         Economic Background.

3.2         Lessons Learned.

References.

4          Practical Measuring Methods.

4.1         Execution of Measuring.

4.2         Dynamic Analysis.

4.3         Measuring System.

4.4         Environmental Influence.

4.5         Calibration and Reliability.

4.6         Remaining Operational Lifetime.

References.

5          Practical Evaluation Methods.

5.1         Plausibility of Raw Data.

5.2         AVM Analysis.

5.3         Stochastic Subspace Identification Method.

5.4         Use of Modal Data in Structural Health Monitoring.

5.5         External Tendons and Stay Cables.

5.6         Damage Identification and Localization.

5.7         Damage Prognosis.

5.8         Animation and Modal Assurance Criterion (MAC).

5.9         Ambient Vibration Derivatives (AVD (r)).

References.

6.          Theoretical Bases.

6.1         General Survey on Dynamic Calculation Method.

6.2         Short Description of Analytical Modal Analysis.

6.3         Equation of Motion of Linear Structures.

6.4         Dynamic Calculation Method for AVM.

6.5         Practical Evaluation of Measurements.

6.6         Theory on Cable Force Determination.

6.7         Transfer Functions Analysis.

6.8         Stochastic Subspace Identification.

References.

7.          Outlook.

7.1         Decision Support Systems.

7.2         Sensor Technology and Sensor Networks.

7.3         Research Gaps and Opportunities.

7.4         International Collaboration.

8.          Examples for Application.

8.1         Post tensional T beam (1956).

8.2         Cable Stayed Bridge in Steel (1996).

8.3         Continuous Box Girder (1979).

8.4         Continuous Steel box Girder (1961).

8.5         Composite Bridge (1979).

8.6         Cable Stayed Bridge (2000).

8.7         Concrete Bridge (1936).

8.8         Bridge Rehabilitation (1998).

8.9         Permanent Monitoring .

8.10       Bridge Rehabilitation.

8.11       Concrete Cable Stayed Bridge (1995).

8.12       Steel Cable Stayed Bridge (1966).