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Prof. Michele CIAVARELLA

 

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Curriculum Vitae (italiano)

SNato a Bari nel 1970, si laurea nel 1994 al Politecnico di Bari in Ingegneria Meccanica con lode e consegue il Dottorato di Ricerca nel 1997 con la tesi Contact Problems with friction and application to the study of Fretting Fatigue (Tutori Prof. G. Monno e Prof. D.A. Hills, Univ. Oxford, UK). Ha svolto diversi periodi di studio o lavoro in università estere, specie inglesi e americane (più recentemente, francesi e tedesche): in particolare, come Research Fellow presso UMich nel 1997, lavorando con il Prof. J.R. Barber sulle instabilità termoelastiche, e con diverse Short-term Fellowships CNR presso U. Oxford, U. Harvard, U. C. Berkeley. Inoltre, da Ott.1998 a Feb.1999 presta servizio come Senior Research Fellow c/o U. Southampton, U.K.. Nel Feb.1999 vince il concorso come Primo Ricercatore CNR-IRIS (per l'iniziativa COMES, COmputational MEchanics of Solids), ora ITC. Negli anni accademici 1999-2001 è professore a contratto di Costruzione di Macchine presso l’università della Basilicata. Nel febbraio del 2000 è invitato da USAF per un ciclo di conferenze su Fretting Fatigue presso MIT, Purdue U., WPAF Res Lab U. C. Berkeley. È stato componente dei comitati scientifico di importanti conferenze internazionale e delle riviste International Journal of Solids & Structures, dal 2005 al 2008 e Fatigue Fract Eng Mat & Structures, dal 2007. È stato relatore di varie tesi di laurea e di dottorato. Ha ricevuto numerosi finanziamenti di ricerca nazionali ed internazionali. È stato invitato a tenere corsi, seminari, lezioni ad invito presso numerose Università e Centri di ricerca internazionali. Ha collaborazioni internazionali pluriennali e in genere ancora attive con Michigan U. (Jim Barber), Oxford U. (David Hills), Harvard U. (Jim Rice, Joost Vlassak, Zhigang Suo), Brown U. (Huajian Gao), Politecnico di Torino (Dino Chiaia, Nicola Pugno, Alberto Carpinteri), Leicester U. (Alan Ponter), Università di Padova (Paolo Lazzarin), Università di Modena (Antonio Strozzi), etc. È autore di oltre 80 lavori su rivista internazionale ed ha un H Index di 17 (Scopus). Parla un ottimo inglese, un buon francese e discretamente tedesco e russo. Dal 2002, in quanto professore associato nel SSD ING-IND/14 presso la II Facoltà dei Ingegneria del Politecnico di Bari, ha tenuto corsi di Meccanica dei materiali e costruzione di macchine e Progettazione meccanica I (L3) e di Progettazione Assistita al Calcolatore e, nel 2006, anche di Meccanica Sperimentale I (LS).

Per maggiori dettagli, si veda il CV in inglese.

Curriculum Vitae (English)

Presently, Associate Professor at Politecnico di BARI (It) from Nov. 2002

Previous employment

From Oct.10 to Oct. 12, Humboldt Senior Research Fellow, Technical Univ. Hamburg Harburg (G), working on squeak on hip prosthesis

From Dec.07 to Sept 08 “Maitre de conférence” at Lab Mécanique des Solides Ecole Polytechnique Palaiseau(Fr) (sabbatical leave)

From Jan. 2000 to Sept. 2006, Senior Research Fellow (part time), University of Southampton, UK

Feb 1999 - Ott 2002, Senior Researcher, Consiglio Nazionale delle Ricerche (Italian National Research Centre), Bari , It

From Oct. 1998 to Feb.1999 Senior Research Fellow (full time), University of Southampton, UK

From Feb. 1998 to Aug.1998, Post-doc with Prof. D. A. Hills, University of Oxford, UK

From Jul. 1997 to Aug.1997, Research Fellow with Prof. JR Barber, University of Michigan, Ann Arbor USA

Education and training

1994-1998. PhD (“dottorato”) in Mech Eng, Politecnico di BARI. From March ‘96 to Aug.’97 at University of Oxford under Prof. DA Hills

1989-1994. “Laurea” in Mechanical Engineering (5 years course) – Magna cum Laude, Politecnico di BARI (It)

Conference organization

* Co-organizer of the world conference ICEM12 (Int Conf on Experimental Mechanics, www.icem12.poliba.it) in Bari, Italy, 29 Aug.-2 Sept. 2004.

* Co-organizer of the world conference Icf11 (International Congress on Fracture, www.icf11.com) in Torino, March 2005

* Co-organizer of the Italian conference on Fracture, in Bari, June 2000

Journal board memberships

Associate Editor, MilleChili Journal, in collaboration with Ferrari spa, and Modena University, from Feb.2010

Member of Editorial Board of International Journal of Solids & Structures, from Sept. 05 to May 08.

Member of Editorial Board of Fat Fract Eng Mat & Struct, from Feb. 07-.

Member of Editorial Board of Acta Tribologica from Dec. 08-.

Research interests

Tribology: friction, wear, contact fatigue

Thermoelastic, Squeal, squeak, and other friction instabilities

Contact mechanics in general at macro, micro, nano scales

Biomechanics of hip and knee prostheses

Coulomb friction and plasticity theorems (Melan, Koiter)

Fatigue and fracture from notched and cracked components

Multiscale modelling particularly of roughness

Indentation testing

Published papers on international journals (total 88)

See list attached.

Selection of special awards & invited lectures

* Invited visiting “maitre de conference” at Ecole Politechnique, Paris Palaiseau, Dec 07/Oct 2008

* Invited at NSF workshop on Friction modelling in Washington 14-15 Oct 2006

* Invited lecture at Thermo-mechanical modelling of solids – Ecole Politechnique, Paris Palaiseau 9-12 July 2007

* Invited by the US Air Force (WOS Windows On Science program) to a cycle of conferences on Fretting Fatigue at MIT (Prof. Subra Suresh), Purdue University (Prof. T. Farris), Wright Patterson AF Research Lab (Dr. Ted Nicholas), UC Berkeley (Prof. Robert Ritchie), February, 2000. For presenting the work on Fretting to the Universities and the labs connected to the MU(Multi University Research Initiative) of the USAF

* Invited by the Inst. of Physics (UK) to give a lecture at the workshop “Tribological Failure Mechanisms in Repeated Rolling Contacts” – Robinson College, Cambridge - 22 July 2003

* Invited by the Inst. of Physics (UK) to give a lecture at the workshop “Contact Mechanics”, Bristol, march 2004

* 1998 Capocaccia National Prize of the Italian Stress Analysis Association (AIAS), for outstanding contribution to the study of frictional contact.

* CNR final price after the grant spent in Feb. 1998 – August 1998 at University of Oxford, UK

*CNR “short term” fellowship travel grants: in July-August 1997, to University of Michigan, visiting Prof. JR Barber, in July-August 1999, to University of Oxford, visiting Prof. DA Hills, in July-August 2000, to University of Harvard, visiting Prof. JR Rice, in July-August 2001, to University of Oxford, visiting Dr. D. Nowell

Selection of grants

*Research project of national interest (PRIN2004), 2005-2006, on “Residual and multiaxial stress states in rolling contact fatigue problems”, PI, funded locally with 30.4kEu

*Vigoni project, 2006-2007 as PI with University of Hamburg and Stuttgard. Funded by DAAD and CRUI, with 5 kEu.

*Galileo project 2004/2005 Egide/ CRUI Conferenza dei Rettori, 2002, with Dr. Robert Wood & Dr. Singellakis (Univ. Southampton):- Optimisation and testing of surface protection coatings for hot components of turbines. Travel Grant. Funded for US$ 5k.

*PROMOMAT project on multiscale computational mechanics for hi/tech composite materials and coatings, involving a large number of companies and academic partners in Italy. 2002-2006 as local-PI with 100 kEu.

*Centre of Excellence in Computational Mechanics (CEMeC), 2001, as co-PI and member of Managing Board. Also, Director of research line on “Thermoelastic and Fatigue contact problems”, at Politecnico di Bari. Funded by Italian Minister for Research and Education with 750 kEu.

*AUTOCON - Brite Euram European Network Framework V Project on "Intermittency in Electrical Connectors", 2002-2006, local PI, Coordinator: Dr. John McBride (Univ. Southampton). Funded locally with 100 kEu.

*Network on COmputational MEchanics of Solids (COMES), CNR, PI, 1999-2001, ITL 40 ml. (20kEu). Funded.

*“Progetto Finalizzato Materiali Speciali per Tecnologie Avanzate II - PFMSTA II” co/PI with DPPI-Politecnico di Ba(Proff. Monno e Demelio), CNR, 1999-2000, ITL.29 ml. (15kEu).

Students

More than 30 Master thesis, and about 5 Phd (Paolo Decuzzi, Vito Tagarielli, Luciano Afferrante, Sonia di Bello (withdrawn), Cosmo Murolo, and collaboration with various phd tesi at U Michigan (Yun Bo Yi, Yong Hoon Jang) and U Oxford (P Blomerus, D Dini).

Teaching activities

* Since 1999 course on Machine Design and Mechanics of Materials (University of Potenza, Politecnico di Bari). Presently teaching 4 undergrad courses per year “Mechanics of Materials and Machine Design”, and “Mechanical Design I”, “Computer Aided Design in Mechanics”, “Experimental Mechanics”. Two courses at Phd level per year “Contact mechanics” and “Tribology”.

Key collaborations

Papers have been written in collaboration with collegues from Michigan U (Jim Barber), Oxford U (David Hills), Harvard U (Jim Rice, Joost Vlassak), Ecole Polytechnique (H.Maitournam), Politecnico di Torino (Dino Chiaia, Nicola Pugno, Marco Paggi, and Alberto Carpinteri), Leicester U in UK (Alan Ponter), Università di Padova (Paolo Lazzarin), Università di Modena (Antonio Strozzi), Univ Hamburg (N. Hoffmann).

Key research results

Few comments follow with cross-reference to publication list.

1) General contact mechanics:

In papers [2,3,9] the procedure devised independently by Cattaneo & Mindlin for Hertzian contact problem with sequential normal and tangential loading has been extended for a general geometry (in 2D and, with some restrictions, also in 3D), permitting the solution of a number of fretting contact problems, and paper [5] introducing the flat and rounded geometry has given rise to a number of recent models for fretting fatigue (notch, crack and more general asymptotic “analogies”). The indentation modulus has been computed for arbitrarily anisotropic materials, indented by tips of any shape [40]. An invited review paper has been written [18] on contact mechanics. More recently, extensions of the celebrated Dundurs’ theorems for “receding” contact have been obtained for “regressive” and “progressive” contact [69], showing in particular a normalising loading parameter useful in summarizing the mechanical response of “almost conforming” contacts of any shape, with potential application in design of many components, ranging from multiple fasteners to artificial joints. In particular, application to compliant layered artificial hip joints and in metal-on-metal hip replacements are presented and assessed versus several literature results in [77].

2) Fretting Fatigue and frictional shakedown

Various classical methodologies have been reviewed, see paper [31], and extensions to crack and notch analogues have been proposed [34, 37, 44] resulting more recently on a general “crack-like notch analogue” model [42] which is an improvement of Subra Suresh’s MIT group “crack analogue” model. Recently [76], some theorems have been derived to show that, despite non-associative, Coulomb’s law can still lead to Melan’s statical theorem on shakedown, provided the structure has uncoupled normal and tangential DOFs. In general, however, coupling gives rise to a richer behavior. Potential applications could be for example in the design of joints, from bolted to turbine blade attachments, or shakedown of frictional geomaterials in pavement design.

3) Rolling Contact Fatigue

This has involved the completion of shakedown maps for a general sliding elliptical contact [41], but also seen the limitations of the plasticity approach in studying what is essentially a fatigue problem, with a re-examination of classical ratchetting experiments by Merwin and K.L. Johnson [49], and those of Su and Clayton [50].

4) Thermo-Elastic Instabilities (TEI)

Various results have been obtained for the thermo-elastic contact of sliding systems namely critical speed and transient behaviour of multidisk clutches and brakes [27, 35, 36], complete assessment of simple rod models [46, 48] or half-plane geometries [52, 53], general existence and uniqueness theorems [51]. More recently, a coupling mechanism between TEI and natural elastodynamics modes (i.e. Dynamic Instabilities) has been found, and denominated TEDI [66, 74, 75].

5) Fatigue and fracture from notches and cracks

Classical and more recent methodologies for estimating the effect of notches in fatigue have been compared [43], the general elasto-plastic asymptotic solution for a sharp notch has been derived [39]. Recently, a generalized Paris law has been proposed [72] using an “asymptotic matching” procedure to use material properties taken from Wohler’s curve of the material to correct the SIF of small cracks. A different but analogous procedure has been proposed in [65] to generalize the use of Kitagawa-Takahashi diagram and of the El Haddad equation for finite life of a specimen.

6) Effect of roughness in mechanical and electrical contacts

The long-disputed problem of scale-dependence of roughness parameters and their role into contact mechanics has been approached with a rigorous investigation using a Weierstrass series profile [19], showing that the contact area predicted within the limits of elasticity theory is a fractal itself, with lower dimension, the higher is the fractal dimension of the profile. This paradoxical result was shown to be true also for the original Archard profile [54], but other macroscopic quantities such as the elastic contact stiffness and the contact resistance where shown to be bounded and dependent on few largest scales rather than the finest one as other [55]. Recently, we have found that classical models can be re-interpreted to fit most results [63,73].

7) Corrugations in railways as a wear-induced instability.

In [81], we have considered the so-called short pitch corrugation “enigma”, which consists in unexplained corrugations of 20-80mm in length in railways particularly strong in BR’s Weast Coast Main Line in England after its electrification in the 1970’s. We showed that classical simple models of used by Prof Johnson and his co-workers in the 1980’s studying corrugations were making a strong and unjustified assumption about constant creepage. The results of a simple model like [81] may not explain all possible short-pitch corrugation evidence, but are not incompatible with the possibility of corrugation existence. Further in [84] we have developed more refined models to study the transient dynamical effect in the contact area, and in [86] we have considered the “enigma” more at large introducing also lateral creepage, and the different receptances corresponding to the change of sleepers after the electrification of the West Main Coast Line in UK, showing some quantitative aspects of short-pitch corrugation are still very difficult to include in the models. Indeed, one of the most tricky aspects is parametric resonance, for which a much simplified model was considered in [85] in collaboration with Hamburg University.

H-index

H/index Google Scholar = 13 (total number of papers 78)

H/index Web of Science (ISI) = 11 (total number of papers 81).


Ultime 15 pubblicazioni

15 most recent journal articles

  1. L. Afferrante and M. Ciavarella A note on thermoelastodynamic instability (TEDI) for a 1D elastic layer: Force control International Journal of Solids and Structures, Volume 44, Issue 5, 1 March 2007, Pages 1380-1390. ISSN: 0020-7683

  2. L. Afferante, M.Ciavarella and J.R.Barber, Sliding thermoelastodynamic instability, Proc.Roy.Soc. (London), Vol.A462 (2006), pp.2161—2176. Print: ISSN 01364-5021 Online: ISSN 1471-2946

  3. A. Klarbring, M.Ciavarella and J.R.Barber, Shakedown in elastic contact problems with Coulomb friction, International Journal of Solids and Structures. 44 (25-26), 8355-8365, 2007. ISSN: 0020-7683.

  4. Ciavarella, M., Strozzi, A., Baldini, A., Giacopini, M., Normalization of load and clearance effects in ball in socket-like replacements, Proc Inst. Mech Eng H Journal of Engineering in Medicine, Volume 221, Number 6, 2007 , pp. 601-611(11). Publisher: Professional Engineering Publishing ISSN 0954-4119.

  5. J.R.Barber, A. Klarbring, M.Ciavarella Shakedown in elastic contact problems for the continuum, Comptes Rendue Mechanique. (8 Janvier 2008) "Duality, Inverse Problems and Non linear Problems" ed J.B.Leblond et X. Markenscoff, Comptes Rendus Mécanique, Volume 336, Issues 1-2, January-February 2008, Pages 34-41, ISSN: 1631-0721.

  6. M.Ciavarella, M.Paggi, J. A. Greenwood, Inclusion of “interaction” in the Greenwood & Williamson contact theory, Wear. Volume 265, Issues 5-6, 25 August 2008, Pages 729-734, ISSN: 0043-1648

  7. Y.Gao, M. Ciavarella, H. Gao, Adhesion maps corrected for strength limit, J Colloids Interf Sci. Volume 315, Issue 2, 15 November 2007, Pages 786-790, ISSN 0021-9797 Publisher: Academic Press

  8. Barber JR Ciavarella, M. On the influence of longitudinal creepage and wheel inertia on short pitch corrugation — a resonance-free mechanism to explain the roaring rail phenomenon, Proceedings of the Institution of Mechanical Engineers, Part J, Journal of Engineering Tribology, Vol. 222 Number 3 / 2008 LEEDS–LYON SYMPOSIUM SPECIAL ISSUE: (2008), pp. 1-11.

  9. Ciavarella, M. , Strozzi, A., Baldini, A., Giacopini, M., Rivasi S. and Rosi, R. On the Applicability of the Loading Parameter F in Pinned Connections with Relevant Initial Clearance, Applied Mechanics and Materials ISSN: 1660-9336 Vols. 5-6 (2006) pp. 155-164.

  10. L. Afferrante, M. Ciavarella, Thermo-Elastic Dynamic Instability (TEDI) in frictional sliding of two elastic half-spaces, Journal of the Mechanics and Physics of Solids Volume: 55, 2007, pp. 744-764. ISSN: 0022-5096

  11. J.R. Barber, M. Ciavarella, L. Afferrante, A. Sackfield, Effect of small harmonic oscillations during the steady rolling of a cylinder on a plane, International Journal of Mechanical Sciences, Volume 50, Issue 9, September 2008, Pages 1344-1353.

  12. N.P. Hoffmann, M. Ciavarella, U. Stolz, C. Weiß, The effect of long-wavelength stiffness variation on wear pattern generation, Journal of Sound and Vibration, Volume 322, Issues 4-5, 22 May 2009, Pages 785-797

  13. L. Afferrante, M. Ciavarella , Short-pitch rail corrugation: A possible resonance-free regime as a step forward to explain the “enigma”?, Wear, Volume 266, Issues 9-10, 24 April 2009, Pages 934-944

  14. L. Afferrante, M. Ciavarella, Thermo-Elastic Dynamic Instability (TEDI) - a review a recent results, Journal of Engineering Mathematics, Vol.61 (2-4), pp. 285-300, 2008.

  15. M. Ciavarella, L. Afferrante, On corrugation models and the "roaring rails" enigma: a simple analytical contact mechanics model based on a perturbation of Carter's solution, Journal of Mechanics of Materials and Structures, Vol. 4 (2), pp. 191-209, 2009.