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On a systematic approach for cracked rotating shaft study: breathing mechanism, dynamics and instability

We present a systematic approach to deal with the modelling and analysis of the cracked rotating shafts behaviour. We begin by revisiting the problem of modelling the breathing mechanism of the crack.

Here we consider an original approach based on the form we give to the energy of the system and then identify the mechanism parameters using 3D computations with unilateral contact conditions on the crack lips.

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On a systematic approach for cracked rotating shaft study: breathing mechanism, dynamics and instability

We present a systematic approach to deal with the modelling and analysis of the cracked rotating shafts behaviour. We begin by revisiting the problem of modelling the breathing mechanism of the crack. Here we consider an original approach based on the form we give to the energy of the system and then identify the mechanism parameters using 3D computations with unilateral contact conditions on the crack lips. A dimensionless flexibility is identified which makes the application of the approach to similar problems straightforward.

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On a systematic approach for cracked rotating shaft study: breathing mechanism, dynamics and instability

We present a systematic approach to deal with the modelling and analysis of the cracked rotating shafts behaviour. We begin by revisiting

the problem of modelling the breathing mechanism of the crack. Here we consider an original approach based on the form we give to the energy of the system and then identify

the mechanism parameters using 3D computations with unilateral contact conditions on the crack lips. A dimensionless flexibility is identified which makes the application

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Nonlinear dynamics of rotating shaft with a breathing crack - CHINA SCHOLARSHIP COUNCIL PhD for 2017

Because of the increasing need of energy, the plants installed by electricity supply utilities throughout the world are becoming larger and more highly stressed. Thus, the risk of turbogenerator shaft cracking is increasing also. The development and propagation of a crack represents the most common and trivial beginning of integrity losses in engineering structures.

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PhD with CSC scholarship on fault mechanics

In the last two decades, considerable observational and theoretical work has been devoted toall aspects of earthquake prediction research, for solving fundamental questions concerningthe mechanics of fault systems, as well as for answering questions regarding earthquakehazard.The european natural observatory of the Corinth Rift (http://crlab.eu), a very rapidlydeforming area (opening strain rate of ~10-6/yr) where one or more earthquakes withmagnitudes above 6 are expected in the coming decades provides a framework in which themechanics of faults can be studied

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Phase field modeling of damage and fracture in polycrystalline materials, support from the Chinese Scholarship Council

The ability of scientists and engineers to exploit, design and process new materials with improved properties has often been fundamental for the technological advances of societies. In fact, advances in many key domains like aerospace, automotive industry, energy, nanotechnology, rely on our ability to engineer new materials and to exploit their properties.

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Nonlinear dynamics of rotating shaft with a breathing crack - CHINA SCHOLARSHIP COUNCIL PhD for 2017

Because of the increasing need of energy, the plants installed by electricity supply utilities throughout the world are becoming larger and more highly stressed. Thus, the risk of turbogenerator shaft cracking is increasing also. The development and propagation of a crack represents the most common and trivial beginning of integrity losses in engineering structures.

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PhD program supported by China Scholarship Council CSC PhD Research Projects for 2016

In the last two decades, considerable observational and theoretical work has been devoted to all aspects of earthquake prediction research, for solving fundamental questions concerning the mechanics of fault systems, as well as for answering questions regarding earthquake hazard.The european natural observatory of the Corinth Rift (http://crlab.eu), a very rapidly deforming area (opening strain rate of ~10-6/yr) where one or more earthquakes with magnitudes above 6 are expected in the coming decades provides a frame

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PhD Research Projects offered for 2015

ParisTech Doctoral Institute and ParisTech local branch in China have launched a coordinated recruitment procedure in the framework of an agreement with the China Scholarship Council (CSC). This program is open to highly qualified Chinese students interested in carrying on doctoral training at ParisTech with financial support of the CSC.

http://paristech-china.com/content/phd-grant-china-scholarship-council

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Deformation rates and localization of an active fault system

The Corinth Rift in Greece is one of the most active extensional regions in the Mediterranean area (Fig. 1). The Corinth Rift Laboratory project (CRL, http://crlab.eu) is based on the cooperation of various european institutions that merge their efforts to study fault mechanics and related hazards in this natural laboratory where numerous continuous observations are made. The present rift is asymmetric and deformation is very localized.

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MODELING COUPLING EFFECTS IN CORD-RUBBER COMPOSITE STRUCTURES

 An analytical model is developed to study the coupling effects in
cord-rubber composite materials. The analytical model takes into account
the mismatch of stiffness between the cords and the rubber matrix
material, and the twist-extension coupling. The transverse deformation,
i.e., normal to the cords direction is based on the normal modes of a
special system which describes the orthotropic and the coupling
behaviour of cord-rubber composites. The equations of motion for the
cord-composite plates are derived using the principle of virtual work.
Results of deformation and stresses are obtained for some typical
cord-rubber composite plates and are compared to the existing solutions.
The results presented illustrate that the coupling effects are

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Shearing effects on the breathing mechanism of a cracked beam section in bi-axial flexure

 The main purpose of this paper is to complete the works presented by
Andrieux and Varé (2002) and El Arem et al. (2003) by taking into
account the effects of shearing in the constitutive equations of a beam
cracked section in bi-axial flexure. The paper describes the derivation
of a lumped cracked beam model from the three-dimensional formulation of
the general problem of elasticity with unilateral contact conditions on
the crack lips. Properties of the potential energy and convex analysis
are used to reduce the three-dimensional computations needed for the
model identification, and to derive the final form of the elastic energy
that determines the nonlinear constitutive equations of the cracked

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Full-scale dynamic response of an RC building under weak seismic motions using earthquake recordings, ambient vibrations and mod

 In countries with a moderate seismic hazard, the classical methods
developed for strong motion prone countries to estimate the seismic
behaviour and subsequent vulnerability of existing buildings are often
inadequate and not financially realistic. The main goals of this paper
are to show how the modal analysis can contribute to the understanding
of the seismic building response and the good relevancy of a modal model
based on ambient vibrations for estimating the structural deformation
under weak earthquakes. We describe the application of an enhanced modal
analysis technique (frequency domain decomposition) to process ambient
vibration recordings taken at the Grenoble City Hall building (France).

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A new parallel sparse direct solver: numerical experiments in large-scale structural mechanics parallel computing


 The main purpose of this work is to present a new parallel direct solver: Dissection solver. It is based on LU
factorization of the sparse matrix of the linear system and allows to
detect automatically and handle properly the zero-energy modes, which
are important when dealing with DDM. A performance evaluation and
comparisons with other direct solvers (MUMPS, DSCPACK) are also given
for both sequential and parallel computations. Results of numerical
experiments with a two-level parallelization of large-scale structural
analysis problems are also presented: FETI is used for the global
problem parallelization and Dissection for the local

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