Il 9 ottobre 2013 ricorrono cinquanta anni dalla data del disastro del Vajont.

La grande frana che si staccò dal Monte Toc il 9 ottobre 1963 precipitando nel bacino artificiale realizzato dalla SADE e producendo devastazione e morte è stata la prima studiata nel mondo come esempio di fenomeni che possono ripetersi sia per cause naturali sia per l’azione dell’uomo.

Nonostante i numerosi studi realizzati, in particolare nei primi anni dopo l’evento, in Italia, e negli ultimi anni, fuori d’Italia, il processo geomeccanico della grande frana del Vajont è ancora oggi non completamente chiarito.

L’Associazione Italiana di Geologia Applicata e Ambientale (AIGA), ha deciso, di organizzare, in occasione del cinquantenario, un Congresso Internazionale che riunisca a Udine gli studiosi di tutto il mondo che si occupano delle frane gigantesche e della frana del Vajont come paradigma delle frane gigantesche e catastrofiche.

Il programma prevede due giorni di comunicazioni scientifiche a Udine (Lunedì e Martedì 7 e 8 Ottobre 2013), un sopralluogo sulla frana (Mercoledì 9 Ottobre 2013) ed infine un ultimo giorno a Udine (Giovedì 10 Ottobre 2013) per trarre le conclusioni e per stilare un manifesto sulle regole etiche da rispettare nella progettazione delle grandi opere.

Un primo annuncio dell’iniziativa è riportato sul sito dell’AIGA

(http://aiga.geoitalia.org).

All’iniziativa hanno concesso il patrocinio l’Università di Udine e l’OGS e la SGI.

Modellazione dell'onda generata dalla frana da Steven Ward dell'università di Santa Cruz. ward@pmc.ucsc.edu 

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Fifty years on from the catastrophic Vajont slide, a tragic event which hit the Italian territory causing about 2000 victims, the Italian Association of Engineering and Environmental Geology (AIGA) is organising a specific International Congress. The Vajont slide, in fact, was considered by many as the reference event both for a new vision concerning geological risk evaluation as well as for the reinterpretation of rock mechanics applied to slope stability, laying the foundations for the development of modern Engineering Geology.

The Congress would like to be a stimulus to analyse the great strides made by Geological Sciences in an objective manner 50 years on, and in particular by Engineering Geology, in the difficult field of giant landslides.

Albeit giant landslides have been recognised and studied at length in mountain chain environments, like for instance the enormous rockslide at Saidmarreh (north-west Iran) – considered the biggest sub-aerial rockslide in the world (18-20 km³) – or the Flims landslide in Switzerland, (volume: 8-10 km³), or the Köfels (volume of 2-3 km³) and the Fernpass rockslide (volume of 1-1.3 km³), both in Austria, the Mayunmarca landslide in Peru (volume of 1-1.6 km³) or all the large landslides in Karakorum, our engineering-geological knowledge on triggering conditions and propagation processes of giant landslides is still limited.

The Vajont slide (volume of about 0.30-0.35 km³) is not dimensionally the most relevant landslide event in the Alpine region; it is however, an episode for scientific reference on a worldwide scale due to the tragic events and the consequences and for having dramatically highlighted the negative influences of reservoirs on the stability of the banks of Alpine slopes especially those with Deep-Seated Gravitational Slope Deformations.

The main objective of the Congress dedicated to the 50^th Anniversary of the Vajont slide, is to promote updated scientific revision on  a global scale considering all the engineering-geological aspects (lithostratigraphical, geomorphological, geomechanical, hydrogeological features) which determined the mobilisation of the great prehistoric M. Toc rockslide and the effects due to the dam construction in an alpine environment (cyclic filling and drawdown of the reservoir level) which caused the catastrophic collapse on the 9^th October 1963.

The overall rexamination of the Vajont slide creates an excellent scientific opportunity to take stock of the current geological and engineering knowledge relative to giant rock slides. These situations, characterising areas of considerable geological complexity, have to be appropriately recognised, delimited and managed as they are particularly vulnerable from a hydrogeological hazard viewpoint.

The Congress programme foresees two days of scientific discussion in Udine (Monday and Tuesday 7^th and 8^th October 2013) dedicated to the Vajont landslide and the main engineering-geological aspects connected to giant rockslides, a guided tour on the enormous Vajont landslide rock mass, at the large detachment surface and at the crown of the dam (Wednesday 9^th October 2013) and finally, the last day in Udine (Thursday 10^th October 2013) to draw conclusions and draw up a manifesto on the ethical rules which should be respected when designing large works.

International Scientific Committee

Hanno già dato l’adesione:

Bromhead, Edward, UK

Chowdhury, R., Australia

Clague, John J., Canadà

Evans Stephen, Canada

Kilburn Christopher, Inghilterra

Ostermann, Marc André, Germania

Petley, David N., UK

Sanders, Diethard, Austria

Stead, Doug, Canadà

Voight, Barry, USA

Wang, Fa Wu, Giappone