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The effects of deterioration models on the value of damage detection information

This paper addresses the effects of the deterioration on the value of damage detection information. The quantification of the value of damage detection information for deteriorated structures is based on Bayesian pre-posterior decision analysis, comprising structural system performance models, consequence, benefit and costs models and damage detection information models throughout the service life

Structural integrity management with unmanned aerial vehicles : State-of-the-art review and outlook

Over the last decade, Unmanned Aerial Vehicles (UAVs) have been used for monitoring construction and operation of civil infrastructure, as well as industrial facilities and power plants. Their operational simplicity along with time-and-cost-related benefits have already rendered them attractive for structural surveying. Nevertheless, the field of UAV research currently lacks a targeted employment

Assessment of terrorism risk mitigation measures for iconic bridges

This paper describes the assessment of the cost efficiency of risk mitigation measures for terrorist attacks with Improvised Explosive Devices (IEDs) for an iconic bridge structure. The assessment is performed with a decision theoretical framework building upon very recent advances in the framework of the COST Action TU1402 on Quantifying the Value of Structural Heath Monitoring. The decision scen

The effects of SHM system parameters on the value of damage detection information

This paper addresses how the value of damage detection information depends on key parameters of the Structural Health Monitoring (SHM) system including number of sensors and sensor locations. The Damage Detection System (DDS) provides the information by comparing ambient vibration measurements of a (healthy) reference state with measurements of the current structural system. The performance of DDS

On damage detection system information for structural systems

Damage detection systems (DDSs) provide information on the integrity of structural systems in contrast to local information from inspections or non-destructive testing (NDT) techniques. In this paper, an approach is developed that utilizes DDS information to update structural system reliability and integrate this information into risk and decision analyses. The approach includes a novel performanc

Reliability assessment of a bridge structure subjected to chloride attack

Prediction of the service lifetime of concrete structures with respect to chloride ingress involves a number of parameters that are associated with large uncertainties. Hence, full-scale measurements are strongly in demand. This paper begins by summarizing statistical distributions based on measurements taken from the Gimsøystraumen Bridge in Norway. A large number of chloride profiles are availab

Environmental sustainable decision making : The need and obstacles for integration of LCA into decision analysis

Decision analysis is often used to help decision makers choose among alternatives, based on the expected utility associated to each alternative as function of its consequences and potential impacts. Environmental impacts are not always among the prioritized concerns of traditional decision making. This has fostered the development of several environmental problems and is nowadays a reason of conce

On the Value of Monitoring Information for the Structural Integrity and Risk Management

This article introduces an approach and framework for the quantification of the value of structural health monitoring (SHM) in the context of the structural risk and integrity management for systems. The quantification of the value of SHM builds upon the Bayesian decision and utility theory, which facilitates the assessment of the value of information associated with SHM. The principal approach fo

System reliability of concrete structures subjected to chloride ingress

The parameters relevant for prediction of service lifetime with respect to chloride ingress are associated with large uncertainties. Full-scale measurements are in demand for conditions which are as homogeneous as possible. The present paper first summarizes statistical distributions which are obtained based on measurements from the Gimsøystraumen bridge in Norway. These probability distributions

Progress of the COST action TU1402 on the quantification of the value of structural health monitoring

This paper summarizes the development of Value of Structural Health Monitoring (SHM) Information analyses and introduces the development, objectives and approaches of the COST Action TU1402 on this topic. SHM research and engineering has been focused on the extraction of loading, degradation and structural features for damage detection and condition assessment, system identification and model upda

Damage detection and deteriorating structural systems

This paper addresses the quantification of the value of damage detection system and algorithm information on the basis of Value of Information (VoI) analysis to enhance the benefit of damage detection information by providing the basis for its optimization before it is performed and implemented. The approach of the quantification the value of damage detection information builds upon the Bayesian d

Value of information-based inspection planning for offshore structures

Asset integrity and management is an important part of the oil and gas industry especially for existing offshore structures. With declining oil price, the production rate is an important factor to be maintained that makes integrity of the structures one of the main concerns. Reliability based and risk- based inspection (RRBI) constitutes an efficient method to optimize inspection planning. Basing

Multi-hazard response analysis of a 5MW offshore wind turbine

Wind energy has already dominant role on the scene of the clean energy production. Well-promising markets, like China, India, Korea and Latin America are the fields of expansion for new wind turbines mainly installed in offshore environment, where wind, wave and earthquake loads threat the structural integrity and reliability of these energy infrastructures. Along these lines, a multi-hazard envir

On the Probabilistic Characterization of Robustness and Resilience

Over the last decade significant research efforts have been devoted to the probabilistic modeling and analysis of system characteristics. Especially performance characteristics of systems subjected to random disturbances, such as robustness and resilience have been in the focus of these efforts and significant insights have been gained. However, as much of the undertaken research and developments

Fatigue model for the structural integrity evaluation applied to a wind turbine concrete shaft, considering corrosion and freeze and thaw degradation

Fatigue is one of the principal damage mechanisms in a slender concrete structure under cyclic loads. And needs to be calculated locally through all the structure, considering the lading conditions and the particularities of concrete. The model presented here is capable to account for the fatigue damage in a probabilistic way, relating the annual loading conditions for each point and the degradati

Reliability analysis and updating of deteriorating systems with subset simulation

An efficient approach to reliability analysis of deteriorating structural systems is presented, which considers stochastic dependence among element deterioration. Information on a deteriorating structure obtained through inspection or monitoring is included in the reliability assessment through Bayesian updating of the system deterioration model. The updated system reliability is then obtained thr

The influence of brittle daniels system characteristics on the value of load monitoring information

This paper addresses the influence of deteriorating brittle Daniels system characteristics on the value of structural health monitoring (SHM). The value of SHM is quantified as the difference between the life cycle benefits with and without SHM. A value of SHM analysis is performed within the framework of the Bayesian preposterior decision theory and requires (1) structural performance modelling a

Efficient structural system reliability updating with subspace-based damage detection information

Damage detection systems and algorithms (DDS and DDA) provide information of the structural system integrity in contrast to e.g. local information by inspections or nondestructive testing techniques. However, the potential of utilizing DDS information for the structural integrity assessment and prognosis is hardly exploited nor treated in scientific literature up to now. In order to utilize the in

Wind turbines and seismic hazard : A state-of-the-art review

Wind energy is a rapidly growing field of renewable energy, and as such, intensive scientific and societal interest has been already attracted. Research on wind turbine structures has been mostly focused on the structural analysis, design and/or assessment of wind turbines mainly against normal (environmental) exposures while, so far, only marginal attention has been spent on considering extreme n