Structural Health Monitoring of Large Civil Engineering Structures (eBook)

Hua-Peng Chen (Autor)

eBook Download: EPUB

2018
587 Seiten
John Wiley & Sons (Verlag)
9781119166634 (ISBN)

Infos

A critical review of key developments and latest advances in Structural Health Monitoring technologies applied to civil engineering structures, covering all aspects required for practical application

Structural Health Monitoring (SHM) provides the facilities for in-service monitoring of structural performance and damage assessment, and is a key element of condition based maintenance and damage prognosis. This comprehensive book brings readers up to date on the most important changes and advancements in the structural health monitoring technologies applied to civil engineering structures. It covers all aspects required for such monitoring in the field, including sensors and networks, data acquisition and processing, damage detection techniques and damage prognostics techniques. The book also includes a number of case studies showing how the techniques can be applied in the development of sustainable and resilient civil infrastructure systems.

Structural Health Monitoring of Large Civil Engineering Structures offers in-depth chapter coverage of: Sensors and Sensing Technology for Structural Monitoring; Data Acquisition, Transmission, and Management; Structural Damage Identification Techniques; Modal Analysis of Civil Engineering Structures; Finite Element Model Updating; Vibration Based Damage Identification Methods; Model Based Damage Assessment Methods; Monitoring Based Reliability Analysis and Damage Prognosis; and Applications of SHM Strategies to Large Civil Structures. 

• Presents state-of-the-art SHM technologies allowing asset managers to evaluate structural performance and make rational decisions
• Covers all aspects required for the practical application of SHM 
• Includes case studies that show how the techniques can be applied in practice

Structural Health Monitoring of Large Civil Engineering Structures is an ideal book for practicing civil engineers, academics and postgraduate students studying civil and structural engineering.

Hua-Peng Chen is Professor of Civil Engineering, Head of Innovative and Smart Structures at the University of Greenwich, UK. He has been working for over 20 years on structural health monitoring, advanced numerical modelling and structural performance assessment. He is a Fellow of the Institution of Civil Engineers (UK) and a Chartered Civil Engineer (UK) with extensive experience in civil engineering practice.

Autor

Hua-Peng Chen is Professor and Director of the Institute for Smart Transportation Infrastructure at East China Jiaotong University, China. He was formerly Professor of Civil Engineering and Head of Innovative and Smart Structures at the University of Greenwich, UK. He received his PhD in Structural Engineering from the University of Glasgow, UK. He has been working for over 20 years on structural health monitoring, advanced numerical modelling and structural performance assessment. He is a Chartered Civil Engineer (UK) and a Fellow of the Institution of Civil Engineers (UK).

Textauszug

1
Introduction to Structural Health Monitoring

Structural Health Monitoring (SHM) is a process of in‐service health assessment for a structure through an automated monitoring system, and it is a key element of cost‐effective strategies for condition‐based maintenance. A SHM strategy consists of many important components including sensing network, data processing and analysis, damage assessment and decision making. SHM technology has the great potential to offer significant economic and life‐safety benefits. However, the application of the SHM technology to actual civil engineering structures is still in its infancy, and it requires advancements in various fields due to its multi‐disciplinary nature. Extensive further works are therefore needed to ensure that infrastructure managers benefit from this emerging technology. This chapter first introduces the development of SHM technology and the framework and strategy of SHM systems. The critical issues and potential benefits of the application of SHM to large civil engineering structures are presented. Finally, the challenges of SHM technologies in civil engineering applications and the required further studies are discussed.

1.1 Advances in Structural Health Monitoring Technology

The structural health monitoring process involves the observation and evaluation of a structure over time using periodically sampled measurements from a sensing system. Structural health monitoring is a popular and growing research field, providing a powerful tool for damage assessment and performance evaluation of engineering structures.

1.1.1 Structural Health in Civil Engineering

Civil infrastructure comprises bridges, buildings, towers, pipelines, tunnels, dams and other types of structures. Their continued safe and economical operation largely depends on proper maintenance and management. In order to evaluate optimal management strategies for existing civil infrastructure, accurate assessment of present and future safety is important and necessary (Ettouney and Alampalli 2012). Maintaining safe and reliable civil infrastructure for daily use is critical to the well‐being of the society. Thus, structural health can be stated as its current capacity for providing intended level of service in a safe and cost‐effective manner against the expected hazards during its service life.

Despite the necessary design methodology initially used, civil engineering structures deteriorate with time. This deterioration is due to various reasons, including failure caused by cyclic traffic loads, effects of environmental factors (e.g. steel corrosion, concrete carbonation) and aging in the construction materials. Also, the deterioration can be caused by infrequent extreme events such as earthquakes, hurricanes and floods. Therefore, structural health will be affected by operational and environmental factors, including normal load conditions, current and future environments and expected hazards during the lifetime. All these factors are variables with uncertainties, so it is difficult to define the structural health in terms of its age and usage and its level of safety to resist severe natural actions. In order to reliably assess structural health and maintain structural safety, continued in‐service monitoring of the structure is essential.

Catastrophic structural failures, such as sudden collapse of the I‐35 highway bridge (NTSB 2008), have highlighted problems associated with aging critical civil infrastructure. Severe natural disasters such as earthquakes and typhoons result in demands for quick condition assessment of civil structures (Brownjohn et al. 2011). Currently, the condition assessment of existing civil infrastructure such as bridges largely depends on visual inspection. This subjective and inaccurate condition assessment methodology has been identified as the most critical technical barrier to effective infrastructure management. For example, condition of bridges is typically expressed in terms of subjective indices on the basis of visual inspection alone. Thus, it is difficult to accurately evaluate structural condition from the inaccurate visual inspection data, even when this may be conducted by experts (Aktan et al. 1998). These issues have driven the research and development on the continuous observation and interpretation of full‐scale performance of civil engineering structures during their service life.

Health monitoring applications based on advanced sensors and real‐time monitoring for civil infrastructure offer great potential for informed and effective infrastructure management. Health monitoring is necessary for civil engineering structures since they may exhibit premature deterioration, structural damage and performance problems, or they may even have aged beyond their expected design life. Health monitoring can be utilised for tracking the responses of a structure along with inputs, if possible, over a sufficient duration to determine anomalies, to detect deterioration and to assess damage for decision making. Damage assessment methods using measured vibration modal data, such as natural frequencies and mode shapes, show promise for the health evaluation of engineering structures (Bicanic and Chen 1997, Chen 1998). Health monitoring can assess the performance of civil structures in a proactive manner using measured data and data interpretation algorithms, in order to correctly evaluate the current condition and to predict the remaining service life.

1.1.2 Aims of Structural Health Monitoring

Structural health monitoring is defined as the process of implementing a damage identification and health evaluation strategy for engineering structures. SHM uses sensing systems and associated hardware and software facilities to monitor the structural performance and operational environments of engineering structures. SHM involves the observation of a structure over time, using periodically sampled structural response and operational environment measurements from an array of sensors and then the evaluation of the current state and future performance of the structure. For long‐term SHM, the output of this process is periodically updated information regarding the capability of the structure to perform its intended function, by considering the inevitable aging and degradation resulting from operational environments (Farrar et al. 2003). Furthermore, SHM is adopted for rapid condition assessment to provide prompt and reliable information regarding the integrity of the structure after extreme events, such as an earthquake or blast loading.

SHM aims to identify structural damage and evaluate the health of the structure using monitored data. Damage is defined here as changes to the material and/or geometric properties of a structure, which affects the current state and future performance of the structure. The objectives of an SHM strategy can be outlined as the following five levels (Farrar et al. 2009).

• Level I: Damage detection, giving a qualitative indication that damage might be present in the structure
• Level II: Damage localisation, giving information about the probable position of damage
• Level III: Damage classification, giving information about the type of damage
• Level IV: Damage assessment, giving an estimate of the extent of damage
• Level V: Damage prognosis, giving information about the safety of the structure, e.g. estimate of remaining useful life

The level in the order given above represents increasing knowledge of the damage state. A higher level usually requires information available about all lower levels. The first two levels, damage detection and localisation, can be generally achieved using vibration based damage detection methods from structural dynamic response measurements. To identify the type of damage, data from structures with the specific types of damage must be available for correlation with the measured data. Analytical models are usually needed to achieve the fourth and fifth levels, damage assessment and prognosis. In general, these two levels may not be achieved without first identifying the type of damage present. Estimates of the future loading, together with predictive deterioration models, are necessary to accomplish the final level for damage prognosis.

SHM strategies offer useful information for optimising maintenance planning of engineering structures in service. To ensure a reliable operation and to schedule maintenance and repair work in a cost‐effective manner, it is necessary to continuously monitor and assess the structural performance and to have an accurate estimation of the remaining useful life. Thus, the SHM strategy integrated with lifecycle management is necessary to calibrate structural assessment and predictions, to enable optimal operation and maintenance of engineering structures and, eventually, to operate the structures beyond their original design life.

1.1.3 Development of SHM Methods

Structural damage identification based on changes in the dynamic response of the structure has been practised in a qualitative manner for a long time. The beginnings of this damage detection method as an area of interest to engineers can be traced back as far as the time when tap‐testing (e.g. on train wheels) for fault detection became common. This field, however, did not really become established in research communities until the 1980s, when much interest was generated in the structural condition of offshore platforms, and later in the health of aerospace structures. Recently, the development of quantifiable SHM methods has been closely linked with the evolution...

Produkt-Details

• Erscheint lt. Verlag: 29.1.2018
• Sprache: englisch
• Themenwelt: Technik ► Bauwesen
• Schlagworte: Bauingenieur- u. Bauwesen • Building Engineering • Civil Engineering • Civil Engineering & Construction • Engineering • guide to structural health monitoring • Hochbau • infrastructure monitoring • in-service damage detection of structures • monitoring based performance assessment • monitoring of civil engineering structures • performance assessment of civil infrastructure • predictive deterioration modeling • smart infrastructure • Structural & Building Engineering • structural damage identification • Structural Damage Identification Techniques • Structural engineering • structural health monitoring and reliability analysis • Structural Health Monitoring of Large Civil Engineering Structures • structural health monitoring (SHM) • Structures • sustainable and resilient civil infrastructure systems • Tief- u. Hochbau / Massivbau • Tragwerk • Tragwerke
• ISBN-13: 9781119166634 / 9781119166634