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Full-Text Articles in Engineering
Hybrid Structural Health Monitoring Using Data-Driven Modal Analysis And Model-Based Bayesian Inference., Jice Zeng
Electronic Theses and Dissertations
Civil infrastructures that are valuable assets for the public and owners must be adequately and periodically maintained to guarantee safety, continuous service, and avoid economic losses. Vibration-based structural health monitoring (VBSHM) has been a significant tool to assess the structural performance of civil infrastructures over the last decades. Challenges in VBSHM exist in two aspects: operational modal analysis (OMA) and Finite element model updating (FEMU). The former aims to extract natural frequency, damping ratio, and mode shapes using vibrational data under normal operation; the latter focuses on minimizing the discrepancies between measurements and model prediction. The main impediments to real-world …
Damage Detection Methodologies For Structural Health Monitoring Of Thin-Walled Pressure Vessels, Arturo Modesto
Damage Detection Methodologies For Structural Health Monitoring Of Thin-Walled Pressure Vessels, Arturo Modesto
Electronic Theses and Dissertations
There is a need in exploring structural health monitoring technologies for the composite structures particularly aged Composite Overwrapped Pressure Vessels (COPVs) for the current and future implementation of COPVs for space missions. In this study, the research was conducted in collaboration with NASA Kennedy Space Center and also NASA Marshall Space and Flight Center engineers. COPVs have been used to store inert gases like helium (for propulsion) and nitrogen (for life support) under varying degrees of pressure onboard the orbiter since the beginning of the Space Shuttle Program. After the Columbia accident, the COPVs were re-examined and different studies (e.g. …
Structural Health Monitoring Using Novel Sensing Technologies And Data Analysis Methods, Seyedmasoud Malekzadeh
Structural Health Monitoring Using Novel Sensing Technologies And Data Analysis Methods, Seyedmasoud Malekzadeh
Electronic Theses and Dissertations
The main objective of this research is to explore, investigate and develop the new data analysis techniques along with novel sensing technologies for structural health monitoring applications. The study has three main parts. First, a systematic comparative evaluation of some of the most common and promising methods is carried out along with a combined method proposed in this study for mitigating drawbacks of some of the techniques. Secondly, nonparametric methods are evaluated on a real life movable bridge. Finally, a hybrid approach for non-parametric and parametric method is proposed and demonstrated for more in depth understanding of the structural performance. …
Analytical And Experimental Study Of Monitoring For Chain-Like Nonlinear Dynamic Systems, Bryan Paul
Analytical And Experimental Study Of Monitoring For Chain-Like Nonlinear Dynamic Systems, Bryan Paul
Electronic Theses and Dissertations
Inverse analysis of nonlinear dynamic systems is an important area of research in the eld of structural health monitoring for civil engineering structures. Structural damage usually involves localized nonlinear behaviors of dynamic systems that evolve into different classes of nonlinearity as well as change system parameter values. Numerous parametric modal analysis techniques (e.g., eigensystem realization algorithm and subspace identification method) have been developed for system identification of multi-degree-of-freedom dynamic systems. However, those methods are usually limited to linear systems and known for poor sensitivity to localized damage. On the other hand, non-parametric identification methods (e.g., artificial neural networks) are advantageous …
Structural Identification Through Monitoring, Modeling And Predictive Analysis Under Uncertainty, Hasan Burak Gökçe
Structural Identification Through Monitoring, Modeling And Predictive Analysis Under Uncertainty, Hasan Burak Gökçe
Electronic Theses and Dissertations
Bridges are critical components of highway networks, which provide mobility and economical vitality to a nation. Ensuring the safety and regular operation as well as accurate structural assessment of bridges is essential. Structural Identification (St-Id) can be utilized for better assessment of structures by integrating experimental and analytical technologies in support of decision-making. St-Id is defined as creating parametric or nonparametric models to characterize structural behavior based on structural health monitoring (SHM) data. In a recent study by the ASCE St-Id Committee, St-Id framework is given in six steps, including modeling, experimentation and ultimately decision making for estimating the performance …
Structural Health Monitoring For Damage Detection Using Wired And Wireless Sensor Clusters, Thomas Terrell
Structural Health Monitoring For Damage Detection Using Wired And Wireless Sensor Clusters, Thomas Terrell
Electronic Theses and Dissertations
Sensing and analysis of a structure for the purpose of detecting, tracking, and evaluating damage and deterioration, during both regular operation and extreme events, is referred to as Structural Health Monitoring (SHM). SHM is a multi-disciplinary field, with a complete system incorporating sensing technology, hardware, signal processing, networking, data analysis, and management for interpretation and decision making. However, many of these processes and subsequent integration into a practical SHM framework are in need of development. In this study, various components of an SHM system will be investigated. A particular focus is paid to the investigation of a previously developed damage …
Structural Condition Assessment Of Prestressed Concrete Transit Guideways, Robert Zachary Shmerling
Structural Condition Assessment Of Prestressed Concrete Transit Guideways, Robert Zachary Shmerling
Electronic Theses and Dissertations
Objective condition assessment is essential to make better decisions for safety and serviceability of existing civil infrastructure systems. This study explores the condition of an existing transit guideway system that has been in service for thirty-five years. The structural system is composed of six-span continuous prestressed concrete bridge segments. The overall transit system incorporates a number of continuous bridges which share common design details, geometries, and loading conditions. The original analysis is based on certain simplifying assumptions such as rigid behavior over supports and simplified tendon/concrete/steel plate interaction. The current objective is to conduct a representative study for a more …