Publications de Jeannot Frieden

Low energy impact damage monitoring of composites using dynamic strain signals from FBG sensors - Part I: Impact detection and localization

John Botsis, Thomas Gmür, Joël Cugnoni, Jeannot Frieden

Fiber reinforced composite materials risk to suffer from subsurface, barely visible, damage induced by transverse relatively low energy impacts. This two-paper series presents a method for the localization of an impact and identification of an eventual dam ...

2012

Low energy impact damage monitoring of composites using dynamic strain signals from FBG sensors - Part II: Damage identification

John Botsis, Thomas Gmür, Joël Cugnoni, Jeannot Frieden

In part I of this two-paper series, a method for the localization of an impact using dynamic strain signals from fiber Bragg grating (FBG) sensors is presented. In this paper, an inverse numerical-experimental method allowing to identify the damage based o ...

2012

Modal numerical-experimental identification method for characterising the elastic and damping properties in sandwich structures with a relatively stiff core

Thomas Gmür, Jeannot Frieden, Michaël Schwaar

In this paper, a mixed numerical-experimental identification procedure for characterising the storage and loss properties in sandwich structures with a relatively stiff core is developed. At the computational level, the proposed method is based upon an ori ...

2012

Characterization of impact damage in fibre reinforced composite plates using embedded FBG sensors

John Botsis, Thomas Gmür, Joël Cugnoni, Jeannot Frieden

EPFL2011

Characterisation of Low Impact Energy Induced Damage in Composite Plates with Embedded Optical Sensors

Jeannot Frieden

Fibre reinforced materials are increasingly employed in aerospace, naval and civil structures because of their low weight and high specific strength and stiffness. A major concern is the inherent susceptibility of composite laminates to barely visible dama ...

EPFL2011

Low-velocity impact damage identification in CFRP plates using inverse numerical-experimental optimization

John Botsis, Thomas Gmür, Joël Cugnoni, Jeannot Frieden

FEUP2011

Vibration-based characterization of impact induced delamination in composite plates using embedded FBG sensors and numerical modelling

John Botsis, Joël Cugnoni, Jeannot Frieden

Dynamic strain signals from embedded fiber Bragg grating sensors are used for experimental modal analysis in carbon fiber reinforced polymer plates. Throughout a series of impact tests, the change of eigen-frequencies due to damage is evaluated for differe ...

2011

High-speed internal strain measurements in composite structures under dynamic load using embedded FBG sensors

John Botsis, Thomas Gmür, Joël Cugnoni, Dragan Coric, Jeannot Frieden

Internal strain measurements in cross-ply carbon-epoxy composite plates under dynamic loads are carried out using embedded FBG sensors. The principle of the FBG interrogation is based on intensity demodulation achieved via a Fabry-Perot filter. To account ...

2010

Damage assessment in CFRP plates based on dynamic measurements with FBG sensors

John Botsis, Thomas Gmür, Joël Cugnoni, Jeannot Frieden

Civil-Comp Press2010

Internal strain measurements in CFRP plates subjected to impact load using FBG sensors

John Botsis, Thomas Gmür, Joël Cugnoni, Jeannot Frieden, Dragan Coric

The British Composites Society2009