Pierre Pegon

Pierre Pegon
European Commission | ec · Joint Research Centre (JRC)

Ingénieur, Docteur Ingénieur, Docteur ès-Science Physique

About

119
Publications
9,998
Reads
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1,439
Citations
Introduction
Current interest is focussed on the improvement of testing method at ELSA: 1) Fatigue testing using limit criteria formulated in displacement, force or both (application to embedded plate testing for ITER) 2) New implementation of the STEP method (Classical PsD method driven by an external software) with increment specified in displacements or force (application to the EQUFIRE project) 3) Improvement of the testing software for visualisation on the client side (test checking, telepresence, etc)
Additional affiliations
January 2013 - present
European Commission
Position
  • Responsible for Reaction Wall and Hoplab Laboratory Activities
Description
  • Lead exp. group, Planning exp. activities, Maintenance, strategic investment and procurement, Quality Insurance implementation, Safety & Security, Advanced testing methods (continuous testing, continuous hybrid testing), Data curation & dissemination
March 2009 - July 2013
European Commission
Position
  • Workpackage Leader and contibutor to SERIE FP7 Project SERIES (Seismic Engineering Research Infrastructures For European Synergies)
Description
  • WP leader and participant to NA “Distributed Database, Data Communication and Access” (19 partners), participant to NA “Qualification of research infrastructures", to JRA “Novel Actuation Systems for Real-Time Control" and to TNA "RETRO" hybrid test
November 1989 - December 2012
European Commission
Position
  • Responsible of Numerical Modelling Activities for Seismic Application
Description
  • Finite Element tools (cast3M), Support to users, Development of 2D &3D mesh generation tools and on-line capability, Models, Studies
Education
May 1984 - April 1988
Grenoble Institute of Technology & University Joseph Fourier - Grenoble
Field of study
  • Advanced Numerical Modelling, ▪ Scientific Software development (Finite Element, Non-Linear Solution Procedures)
September 1981 - November 1983
Grenoble Institute of Technology
Field of study
  • Numerical Modelling, Scientific Software development, Experimental activities
September 1975 - July 1980
Grenoble Institute of Technology
Field of study
  • Engineering Sciences, Fluid & Solid Mechanics, Mathematics, Numerical methods in Engineering

Publications

Publications (119)
Article
This paper presents an overview of the developments performed at the European Laboratory for Structural Assessment (ELSA) of the Joint Research Centre of European Commission concerning the new generation of servo-hydraulic real-time digital controller/acquisition system adopted in large scale experiments. The hardware architecture is based on Ether...
Article
Full-scale testing of a two-storey flat slab structure is reported, undertaken in the SlabSTRESS research project; the construction and testing were planned and carried out at the ELSA laboratory of the European Commission's Joint Research Centre. The dimensions are three bays by two, spans 4.5 and 5 m, slab thickness 0.2 m, interstorey height 3.2...
Conference Paper
Full-text available
The SlabSTRESS project investigated the behaviour of a full-scale Reinforced Concrete flat slab building under both gravity loads and seismic lateral actions. The two-storey structure had 9.0 m × 14.5 m plan dimensions, three bays in the loading direction and two orthogonally. This layout enabled to test simultaneously three types of slab-column co...
Chapter
This work introduces a method for the identification of linear stiffness and viscous damping parameters from a one-degree-of-freedom force-displacement cycle. Using an original approach, the stiffness parameter is derived by a least-square formula from the discrete input force-displacement point coordinates of the loop. The damping ratio is obtaine...
Book
Full-text available
The European Commission‘s Joint Research Centre (JRC) gives leading researchers from across Europe and beyond access to its world-class facilities and laboratories, enabling state-of-the-art experimental research, collaboration and capacity building with a European dimension. It does so through the programme for open access to JRC research infrastr...
Conference Paper
Full-text available
Flat slab buildings for commercial, office and residential use are built in many countries. Yet, their behaviour under seismic and gravity actions is still not very well understood. Many studies have been carried out in North America but European research is lagging behind and currently Eurocode 8 does not cover the design of buildings with flat sl...
Conference Paper
Full-text available
The EQUFIRE project aims to study the post-earthquake fire performance of steel frame structures and is part of the Transnational Access activities of the SERA project (www.sera-eu.org) at the ELSA Reaction Wall of the European Commission-Joint Research Centre. As it has happened in many historical occasions, after an earthquake, earthquake-induced...
Technical Report
Full-text available
This work introduces a method for the identification of linear stiffness and viscous damping parameters from a one-degree-of-freedom force-displacement cycle. Using an original approach, the stiffness parameter is derived by a least-square formula from the discrete input force-displacement point coordinates of the loop. The damping ratio is obtaine...
Article
This article presents a novel approach to model validation and to the calibration of complex structural systems, through the adoption of heterogeneous (numerical/physical) simulation based on dynamic substructuring (HDS). HDS isolates the physical sub-system (PS) that contains the key region of nonlinear behavior of interest and is tested experimen...
Article
Data are one of the main assets of earthquake engineering. Laboratory experiments can be extremely expensive and time consuming to replicate and, therefore, long-term preservation of experimental data and sharing the data with users has become one of the disciplinary priorities. There is a growing demand for international partnerships, which create...
Conference Paper
An upgraded hybrid cyber-physical technique was introduced to assess the seismic response of a reinforced concrete motorway bridge and the effectiveness of the friction-pendulum seismic isolation. The two independent roadway bridge was built in the 1960s in Italy and it spans over twelve couples of portal frame piers. Two of the piers (scale 1:2.5)...
Article
Modern seismic codes allow for inelastic deformation in dissipative zones during design earthquakes, accepting damage to the relevant structural parts to a certain extent. Experience has shown that repair work is needed after moderate to strong earthquakes. The use of structural systems that are easily repairable is therefore beneficial in seismic...
Article
Full-text available
The response of 13 reinforced concrete shear walls submitted to successive seismic tests has been postprocessed to produce time histories of secant stiffness and displacement oscillation amplitude. For every wall an envelope curve of displacement amplitude versus stiffness is identified which is fairly modelled by a straight line in double logarith...
Article
Full-text available
The SAFE experimental programme consists of a series of 10 specimens of shear walls, with different reinforcement ratios, tested until their ultimate capacity under seismic input motion by the pseudo dynamic method. A unique input signal is used, calibrated for controlling the seismic demand. Its input central frequency is selected so that for some...
Article
The unpredictable consequences of earthquakes have proven the necessity to study the shear mechanism of low-rise reinforced concrete walls further. Experimental testing remains the preferred approach to gather insight into the workings of the material and structural elements as the complex behavior of reinforced concrete does not lend itself to wid...
Conference Paper
Full-text available
In the last two decades, the increasing complexity of engineering systems boosted the development of very efficient simulation methods based on partitioning. In view of coupling dynamic parts of hybrid systems, the finite element tearing and interconnecting approach emerged as the most promising technique. Nonetheless, there is still a lack of a co...
Conference Paper
Full-text available
In the last two decades, the increasing complexity of engineering systems boosted the development of very efficient simulation methods based on partitioning. In view of coupling dynamic parts of hybrid systems, the finite element tearing and interconnecting approach emerged as the most promising technique. Nonetheless, there is still a lack of a co...
Article
Full-text available
The European scientific community is currently highly fragmented, with each laboratory holding experimental data, stored in some cases in a non-structured way. As a consequence, dissemination and use of experimental results outside the laboratory where they are produced can be problematic. This leads to wasteful duplication of tests and ultimately...
Article
This paper deals with the assessment of the seismic response of an old reinforced concrete (RC) viaduct and the effectiveness of friction-based retrofitting systems. Emphasis has been paid to an old bridge not properly designed for seismic action consisting of twelve portal piers which support a thirteen-span bay deck for each independent roadway....
Chapter
Full-text available
The assessment of the seismic performances of an old concrete bridge was conceived within the RETRO Transnational Activity funded by the SERIES research project. The installation of a couple of isolation devices -one per column- for each pier portal frame interposed between the cap beam and the deck was proposed as seismic retrofit, which fully com...
Conference Paper
Full-text available
Hybrid Simulation with Dynamic Substructuring (HSDS) defines a class of hybrid numerical-experimental techniques capable of simulating the nonlinear response of a dynamic system. As far as complexity of emulated structures grows, the role of integration algorithms becomes more and more crucial. In fact, today control systems run at sampling times o...
Conference Paper
Conventional seismic design philosophy is based on dissipative structural response, which implicitly accepts damage of the structure under the design earthquake and leads to significant economic losses. Repair of the structure is often impeded by the permanent (residual) drifts of the structure. The repair costs and downtime of a structure hit by a...
Article
In common with many scientific disciplines, earthquake engineering research is increasingly focusing on large international collaborations to address complex problems. Data integration is a key requirement to facilitate joint research efforts and improve experimental outcomes. Development and implementation of a novel virtual database is presented,...
Article
Full-text available
This paper addresses the strength and deformation capacity of stiff squat shear wall subjected to monotonic and pseudo-static cyclic loading using experiments and analysis. Reinforced concrete squat shear walls offer great potential for lateral load resistance and the failure mode of these shear walls is brittle shear mode. Shear strength of these...
Data
Full-text available
The RETRO project aims at studying the seismic behaviour of existing reinforced concrete bridges (RC) and the effectiveness of innovative retrofitting systems. Emphasis has been paid on old bridges generally not properly designed for seismic action. On the basis of a previous experimental campaign consisting of cyclically imposed displacements on 1...
Conference Paper
Full-text available
Within the frame of the European project IRIS, five reinforced concrete walls have been tested in shear at the ELSA. The thickness of the wall was exceptionally large (40cm) for this kind of test. The testing setup was able to apply quasistatically a shear force of up to 12 MN by means of four horizontal actuators and the vertical load and rotation...
Conference Paper
Full-text available
The “Retro” project funded by the European commission within the Series-project aims at studying numerically and experimentally the seismic behaviour of an old existing reinforced concrete bridge with portal frame piers and the effectiveness of different isolation systems. An experimental test campaign is performed at ELSA Laboratory of JRC (Ispra,...
Conference Paper
At the beginning of the project, the access and exchange of data within the European scientific community was highly fragmented and the diffusion of information among laboratories was not sufficient. The outcome of an inquiry performed among partner laboratories at the beginning of SERIES showed that data storage in an unstructured way was the comm...
Conference Paper
The European Laboratory for Structural Assessment performs tests of full-size specimens of civil engineering structures and contributes to the scientific knowledge on the behaviour of different structural typologies. Many of the testing campaigns are oriented to the improvement of design standards such as the Eurocode8, which is the European standa...
Conference Paper
Full-text available
Experimental methods such as hybrid or pseudo-dynamic tests are always subjected to experimental errors which effect on the obtained response is important to assess. An analytical linear model formulated on state-space equations has been developed for a multi DoF hybrid testing system including the components of the control and the specimen. For an...
Conference Paper
The European Laboratory for Structural Assessment (ELSA) is involved in the development of advanced control strategy for improving the performances of the servo-control systems used for pseudo-dynamic testing on large civil structures or on subcomponents using substructuring method. Two research lines are pursued: advancing of control algorithm and...
Conference Paper
The present paper focuses on the research activities, namely networking activities and pseudo-dynamic test projects, being carried out at the European Laboratory for Structural Assessment (ELSA) of the Joint Research Centre of the European Commission (EC), as part of the Seismic Engineering Research Infrastructures for European Synergies (SERIES) p...
Conference Paper
Full-text available
In the IRIS project (European 7 th framework program) we have designed an original experimental setting for assessing the structural fragility of thick shear-walls. The main motivation is to improve the understanding of the non-linear behaviour under seismic loads of structures typical for the existing NPPs. In this context it is not only important...
Article
By comparison of dynamic and pseudo-dynamic tests, it is shown that conventional construction materials exhibit pure hysteretic damping and consequently, when quasistatic restoring forces are measured directly, the addition of viscous damping in the equation of motion must be avoided unless it is intended to reflect missing physical elements. Equal...
Conference Paper
Full-text available
The classic step-by-step Pseudo-dynamic (PsD) method is relatively easy to implement, including the case of substructuring, but obliges to a very low execution speed of the test. A big improvement is introduced by the continuous PsD method that allows for a faster execution and improves the quality of the results by making a more effective use of t...
Conference Paper
The classic step-by-step Pseudo-dynamic (PsD) method is relatively easy to implement, including the case of substructuring, but obliges to a very low execution speed of the test. A big improvement is introduced by the continuous PsD method that allows for a faster execution and improves the quality of the results by making a more effective use of t...
Article
A novel partitioned algorithm able to solve ODEs arising from transient structural dynamics is presented. The spatial domain is partitioned into a set of disconnected subdomains owing to computational or physical considerations, and continuity conditions of velocity at the interface are modelled using a dual Schur formulation, where Lagrange multip...
Article
Full-text available
A general approach to the definition and assessment of response errors in dynamic and pseudo-dynamic tests is presented. By use of complete measurements during the test, the characteristics of the experimental and the prototype system can be estimated by means of a linear ideal representation. This allows comparing quantitatively in terms of eigenf...
Article
Full-text available
The deleterious effect of control errors in the obtained response for shaking-table, pseudo- dynamic and hybrid tests can be quantified in a standard way by assessing the frequency and damping distortion in the obtained response as identified from equivalent linear models. The identified linear models are based only on the measurements done during...
Conference Paper
Real-time testing with dynamic substructuring (RTDS) is a novel form of hybrid numerical-experimental testing technique used to simulate structures subjected to seismic loadings. By imposing compatibility and equilibrium conditions at the interface between the numerical substructure and the physical substructure, respectively, the substructures are...
Article
In order to predict the dynamic response of a complex system decomposed by computational or physical considerations, partitioned procedures of coupled dynamical systems are needed. This paper presents the convergence analysis of a novel parallel interfield procedure for time-integrating heterogeneous (numerical/physical) subsystems typical of hardw...
Article
This work presents the development and implementation of a domain decomposition approach for solving dynamics problems involving continuous testing with analytical substructuring in the non-linear range. This approach implements an inter-field parallel time integration procedure suitable to work with an explicit experimental synchronous process usi...
Chapter
The ELSA laboratory is equipped with a large reaction-wall facility and has acquired its best expertise on the development and implementation of innovative experimental techniques mainly related to testing large-scale specimens by means of the pseudo-dynamic method. Relevant achievements within the testing techniques, such as the continuous pseudo-...
Conference Paper
Real-Time Hardware-in-the-loop (RTHIL) is a novel form of heterogeneous numerical-experimental testing capable of assessing the behaviour of structures subjected to dynamic loadings. The technique involves splitting the emulated structure being tested into two parts: the Physical Substructure (PS), which contains a key region of interest and is exp...
Conference Paper
During the last decade, the European Laboratory for Structural Assessment (ELSA) has played a major role in Europe in the execution of seismic tests on large structural models. Most of the tests performed at ELSA have been developed in collaboration with many research centres and have produced results of great value for the validation of several ch...
Conference Paper
In order to meet the objectives of earthquake risk mitigation worldwide and progress towards performance based seismic design and assessment, there is also a need for experimental facilities capable of handling complex structures and systems, to understand real effects of phenomena like soil-structure interaction and to combine physical and numeric...
Conference Paper
The ELSA laboratory is provided with a large reaction-wall facility and has acquired its best expertise on the development and implementation of innovative experimental techniques mainly related to testing of large-scale specimens by the pseudodynamic method. Important examples are represented by the bidirectional tests performed on multi-storey bu...
Article
Pseudo-dynamic tests on a large-scale model of an existing six-pier bridge were performed at the ELSA laboratory using the substructuring technique. Two physical pier models were constructed and tested in the laboratory, while the deck, the abutments and the remaining four piers were numerically modeled on-line. These tests on a large-scale model o...
Chapter
Full-text available
Structure sous seismes: expérimentation en laboratoire
Conference Paper
Full-text available
This paper describes the principles of continuous pseudodynamic testing as it is currently implemented at the ELSA laboratory as a seismic testing technique for large-size specimens. Then, by means of a linear model, the effect of the control error on the test response is characterised mainly as a decrease on the apparent damping of the structure....
Article
Full-text available
Within the VAB research program, pseudodynamic tests on a large-scale model of an existing bridge were carried out in the reaction wall of the ELSA laboratory of the Joint Research Centre, applying the substructuring method. Asynchronous input motion, generated for the bridge site, was considered at the base of the piers and abutments. Non-linear s...
Article
Full-text available
Palavras Chave: Ensaios Sísmicos, Ensaios Pseudo-dinâmicos, Avaliação, Reforço RESUMO O Laboratório ELSA (Laboratório Europeu de Avaliação Estrutural), do Centro Comum de Investigação (CCI) da Comissão Europeia, em Ispra, Itália, desenvolve desde 1992 uma intensa actividade de investigação de carácter experimental e numérico no domínio do comportam...
Article
Full-text available
A representative model of built cultural heritage structure was designed using 2D and 3D numerical modelling in order to test at the laboratory and its behavior was also characterized. Large blocks assembled with mortar and masonary were used to make the structures. The results revealed that the deformation and damage patterns can be predicted accu...
Article
Full-text available
This work presents an alternative definition of the numerical angular frequency and numerical damping ratio, within the framework of direct time integration of second-order differential equations. The classical approach, based on the amplification matrix concept, deals with the ability of the numerical schemes to deliver an accurate response in tim...
Article
Full-text available
The paper describes the distinctive features of the pseudo-dynamic test method as implemented at the ELSA reaction-wall facility. Both hardware and software aspects are considered. Particular attention is devoted to the digital control system and to a coupled numerical–experimental substructuring technique allowing realistic earthquake testing of v...
Article
Full-text available
77 Abstract The ELSA laboratory is provided with a large reaction-wall facility and has acquired its best expertise on the development and implementation of innovative experimental techniques mainly related to testing of large-scale specimens by the pseudo-dynamic method. Important examples are represented by the bidirectional tests performed on mu...
Article
Full-text available
: The results of the seismic tests on several reinforced-concrete shear walls and a four-storey frame are analysed in this paper. Each specimen was submitted to the action of a horizontal accelerogram, with successive growing amplitudes, using the pseudodynamic method. An analysis of the results allows knowing the evolution of the eigen frequency a...
Article
The seismic performance of civil engineering structures may be estimated by using two levels of modelling. At the local level, each constituent has its own constitutive law and geometric finite element support. The main phenomena such as the cracking and the crushing of concrete and masonry could be reproduced by using the continuous damage or plas...
Technical Report
Full-text available
This document presents the implementation of a fully automatic algorithm for the meshing of structures made of blocks connected together by joint interfaces. Starting from the definition of the corner nodes of the blocks, the algorithm is able to produce the mesh of each block in such a way the faces that are in contact are topologically identical....
Conference Paper
Full-text available
In this paper, two different time-domain methods are proposed. Both have been successful in the identification of the natural frequencies, damping ratios and mode shapes of large structures seismically tested by using the pseudodynamic method. The first method is formulated as a spatial model in which the stiffness and damping matrices are directly...
Article
Full-text available
In this paper, we discuss procedures for computing the mesh movement in staggered FSI-simulations. The mesh movement is divided into a global and a local level. The global level is based on the solution of an incremental linear-elastic solid model using the structure movement as Dirichlet boundary conditions, and error estimates to guide the node r...