Niu, Yan: Online force reconstruction for Structural Health Monitoring. 2018
Inhalt
- Titelblatt
- Acknowledgements
- Contents
- Nomenclature
- Abstract
- Kurzfassung
- 1 Introduction
- 1.1 Introduction to Structural Health Monitoring (SHM)
- 1.2 Motivation
- 1.3 Basic idea of online force reconstruction
- 1.4 State of the art
- 1.5 Original contributions
- 1.6 Organization of the thesis
- 2 Theoretical foundations
- 2.1 Structural model construction
- 2.1.1 Second-order structural model
- 2.1.2 Continuous-time state-space structural model
- 2.1.3 Discrete-time state-space structural model
- 2.1.4 Experimental Modal Analysis (EMA)
- 2.1.5 Operational Modal Analysis (OMA)
- 2.1.6 Model updating
- 2.2 Observer
- 2.3 Unknown Input Observer (UIO)
- 2.4 Kalman filter
- 2.5 Kalman-Bucy filter
- 2.6 Real-time executable state and input estimation algorithms
- 2.6.1 Proportional-Integral observer (PI observer)
- 2.6.2 Simultaneous State and Input Estimator (SS&IE)
- 2.6.3 Kalman Filter and a Recursive Least-Squares Estimator (KF+RLSE)
- 2.6.4 Recursive Three-Step Filter (RTSF)
- 2.6.5 Kalman Filter with Unknown Inputs (KF-UI)
- 2.6.6 Augmented Kalman Filter (AKF)
- 2.6.7 Steady-State Kalman Filter and a Least-Squares Estimator
- 2.7 Correlation of the process noise and the measurement noise
- 3 Problem formulation and methodology
- 3.1 Force reconstruction is a kind of inverse problem
- 3.2 Ill-posed nature in force reconstruction
- 3.3 From ill-posedness to well-posedness in online force reconstruction
- 3.4 Methodology for online force reconstruction with structural modal parameters identified by experimental modal analysis
- 3.5 Methodology for online force reconstruction with structural modal parameters identified by operational modal analysis
- 3.6 Methodology for the reconstruction of a distributed force with unknown spatial distribution
- 4 Proposed algorithm modifications
- 4.1 Simultaneous State and Input Estimator for Linear systems (SS&IE_L)
- 4.2 Steady-state of KF+RLSE
- 4.3 Generalized Kalman filter with unknown inputs (G-KF-UI)
- 4.3.1 Difference and relationship between the KF-UI and the RTSF
- 4.3.2 Proposed modifications to the KF-UI
- 4.3.3 Generalized form of the KF-UI
- 4.3.4 Steady-state of G-KF-UI
- 4.4 Modified Steady-State Kalman Filter and a Least-Squares Estimator
- 5 Study on application-oriented algorithm selection
- 5.1 From mathematics to practical requirements
- 5.1.1 Assumption on inputs
- 5.1.2 Assumption on initial state estimate
- 5.1.3 Assumption on direct feed-through
- 5.1.4 Mathematical conditions on system matrices
- 5.2 Benchmark study
- 5.2.1 Introduction to the benchmark structure
- 5.2.2 Structural model construction for the benchmark structure
- 5.2.3 Considered forces
- 5.2.4 Test using PI observer
- 5.2.5 Test using KF+RLSE
- 5.2.6 Test using SSIE_L
- 5.2.7 Test using AKF
- 5.2.8 Test using KF-UI and G-KF-UI
- 5.2.9 Test using SSKF+LSE and MSSKF+LSE
- 5.2.10 Summary
- 5.3 Proposed guidance for algorithm selection
- 6 Practical application to the Canton Tower
- 6.1 Introduction
- 6.1.1 Canton Tower
- 6.1.2 SHM system for the Canton Tower
- 6.1.3 SHM benchmark study for the Canton Tower
- 6.1.4 Organization of this chapter
- 6.2 Methodology for wind load reconstruction for the Canton Tower
- 6.3 Operational modal analysis for the Canton Tower
- 6.3.1 Sensor deployment and field measurements
- 6.3.2 Stationarity test
- 6.3.3 OMA results
- 6.3.4 Discussion
- 6.4 Model updating for the Canton Tower
- 6.4.1 Modified reduced-order FE model of the Canton Tower
- 6.4.2 Model updating method
- 6.4.3 Model updating results
- 6.5 Algorithm selection
- 6.6 Wind load reconstruction for the Canton Tower
- 6.7 Summary
- 7 Summary and outlook
- Bibliography
- A Derivation of the SS&IE_L
- B Proof of the equivalence of filter equations of the KF-UI and the RTSF
