Course outline

Monitoring and auscultation

From sensors to useful signals for concrete evaluation and monitoring

Before getting any observable from a measurement, signals have to be recorded after a wave or field has been interacting with concrete. The participants will get an overview of signal sampling and acquisition main features together with an insight of signal processing in the time and frequency domains. Notions about interferometry will be provided in relation to ultrasonic and fibre optic measurements.
Lecturer: Dr Odile Abraham (Ifsttar)

From signals to useful parameters: combination and data fusion

NDT parameters are not necessarily directly related to material or structural parameters. They have to be translated. An overview on calibration, combination of methods/data fusion to improve the results will be given.
Lecturer: Dr Ernst Niederleithinger (BAM)

Probability of Detection (PoD), Receiver Operating Characteristic (ROC)

How to connect parameters from NDT and monitoring to reliability and probability assessment? Studies on structural reliability or asset management are based more and more on risk assessment. To include NDT and monitoring data into this framework, their reliability must be known. The basic tools to do so, probability of detection and receiver operating characteristic curves will be explained.
Lecturer: Dr Ernst Niederleithinger (BAM)

Demonstrations and exercises on monitoring and auscultation

Group on Acoustic Emission: How to locate and detect cracking?

The Acoustic Emission method (AE) records real time acoustic signal from crack initiation and propagation. Specific signal processing tools can be used to identify and characterise these signal and to locate the origin. The measurement equipment is demonstrated. The participants will be able to work with AE software to identify and localize an artificial event.

Group on Fibre Optics: How to size a crack ?

The advantages of fibre optics to monitor temperature and deformation as well as crack opening will be illustrated through various on-site and laboratory experiments. Knowledge and understanding of the transfer function required to recover quantitative information about crack opening will be provided. A lab demonstration will be carried out.

Group on ToF: How to monitor and get relevant information about fatigue with ultrasonic conventional measurements ?

Ultrasonic body waves are classically used in NDT to either detect localized damages or hidden geometries or to identify material mechanical properties. The links between ultrasonic wave velocities and material properties will be given. Up-to-date information about existing equipments will be provided and their relevance to fatigue monitoring addressed. The participants will process experimental signals recorded during a fatigue experiment.

Group on CWI: Coda wave interferometry a new very sensitive monitoring tool for concrete.

The scattering and reverberation of ultrasonic waves in concrete structure, often viewed as noise in conventional NDT/SHM, is shown here to be of great value to get information on early age damages invisible otherwise. The participants will get to know the basic of CWI signal processing as well as a description about the present state of the art of experimental set-ups with embedded or external sensors. Environmental bias will be highlighted and ways to remove them addressed. The participants will process of the data from a controlled experiment on a beam under loading test.

Structural and action models

Fatigue verification of structural elements based on data from monitoring

Collected data from several long-term monitoring campaigns including three bridges and one wind turbine tower are analysed and fatigue relevant data are extracted. This fatigue action effect is used to perform the fatigue verification of structural elements using conventional code-based verification formats. Finally, the benefits of explicit use of data from monitoring is highlighted.
Lecturer: Prof. Eugen Brühwiler (EPFL)

Fatigue of R-UHPFRC structural elements

The main research findings from experimental campaigns are synthesized first in terms of evolution of fatigue stresses in UHPFRC and steel rebars over the fatigue duration. Then, rules are deduced for the fatigue design of bridge elements. Finally, these design provisions are applied for the design of a short-span railway bridge.
Lecturer: Prof. Eugen Brühwiler (EPFL)

Assessment of extreme values of effects in structures

The assessment of extreme values of effects in structures will be based on extreme value theory and use of temporal series (coming either from monitoring or calculations). A short overview of statistics of standards will be made (review periods and return values), explanation of extreme value theory and some examples of application. The exercices will be made with R project, based on monitoring data.
Lecturer: Dr Franziska Schmidt (Ifsttar)

Updating of structural models

Updating of structural models will be based on monitoring data and a simple structural models. A short overview of existing methods will be given, with some simple example. Here again, the main part will be exercises, still to be defined with the monitoring data that will be used all over the training week.
Lecturer: Dr Franziska Schmidt (Ifsttar)

Reliability, risk and decision analyses

Uncertainty and structural reliability assessment

The lecture of uncertainty and structural reliability assessment contains the fundamentals of uncertainty modelling in civil engineering and the methods of structural reliability and structural system reliability analysis. The uncertainty modelling provides the types of uncertainties and the approaches to model these in a structural reliability analysis. Methods for structural reliability analyses like Monte Carlo Simulation and FORM are introduced and their application in a structural system reliability analysis is demonstrated.
Lecturer: Prof. John Dalsgaard Sørensen (AAU)

Decision and structural information analyses

The lecture on decision and structural information analyses provides a summary on decision scenario development, decision modelling and analysis methods encompassing prior, pre-posterior, posterior decision and value of information analysis in the context of structural health information for civil engineering structures. Building upon the structural reliability methods and uncertainty modelling methods, the lecture provides models for structural health information and actions such as non-destructive testing results, monitoring, load testing, load control and repair.
Lecturer: Assoc. Prof. Sebastian Thöns (DTU)

Special lectures (complementary skills)

Artificial Intelligence and Intellectual Property Opportunities

There is no alternative to Artificial Intelligence. The fourth industrial revolution is based on professional, private or retail robots which imit and increase human intelligence. In 2025, the market will be valued at 52 trillion US dollars. In this context, the current review examines how the Artificial Intelligence is giving opportunities to Intellectual Property era to-day and the next future.
Lecturer: Alice Pezard

Economical analysis and societal issues: transport in economy, women in transport, greenhouse gas

The session will investigate to what extent mobility is at the core economic and social inclusion. At the horizon H2020, inclusive mobility raises two related issues: do mobility plans take into account the different individual mobility patterns, especially those of women? And what are the conditions to promote a low carbon mobility? Relating the 2 issues we may ask if the women could be the key actors of a low carbon mobility?
Lecturer: Dr Ariane Dupont-Kieffer