The 1963 Vajont Landslide: 50th Anniversary

Barla, Giovanni Battista; Paronuzzi, Paolo

doi:10.1007/s00603-013-0483-7

Cited by 63 publications

(29 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The catastrophic Mt. Toc failure of 9 October 1963 (volume of about 300 million m 3 ) remobilized a large prehistoric rockslide (Semenza, 1965;Hendron and Patton, 1985;Semenza, 2001;Paronuzzi and Bolla, 2012;Barla and Paronuzzi, 2013) that had already been subjected to considerable rock mass damage caused by the ancient slope instability. As a consequence, the 1963 en masse remobilization determined a further increase in folding, fracturing, faulting, and rock disintegration within the failed rock mass.…”

Section: Introductionmentioning

confidence: 99%

Gravity-induced rock mass damage related to large en masse rockslides: Evidence from Vajont

Paronuzzi

Bolla

2015

Geomorphology

Self Cite

View full text Add to dashboard Cite

Section: Introductionmentioning

confidence: 99%

Gravity-induced rock mass damage related to large en masse rockslides: Evidence from Vajont

Paronuzzi

Bolla

2015

Geomorphology

Self Cite

View full text Add to dashboard Cite

“…The geological evidence proving the existence of an ancient failed mass forming the northern toe of the Mt. Toc slope is well documented (Semenza 1965(Semenza , 2001Hendron and Patton 1985;Paronuzzi and Bolla 2012) and today widely accepted (Barla and Paronuzzi 2013). Nevertheless, a progressive failure phenomenon actually occurred and played an important role in determining the progressive instability of the Mt.…”

Section: Discussionmentioning

confidence: 95%

“…2) is an excellent example, on a world scale, showing the complexity of some large rock slope instabilities that include the change from an initial prevailingly ductile behavior to a final very rapid en bloc collapse (Barla and Paronuzzi 2013). This unexpected transition from ductile to brittle behavior, with its disastrous consequences, was considered ''a radical and inconceivable change'' (Müller 1964) and this remains a phenomenon that is hard to explain, despite considerable progress in rock mechanics since 1963.…”

Section: Introductionmentioning

confidence: 99%

Brittle and Ductile Behavior in Deep-Seated Landslides: Learning from the Vajont Experience

2015

Self Cite

View full text Add to dashboard Cite

This paper analyzes the mechanical behavior of the unstable Mt. Toc slope before the 1963 catastrophic collapse, considering both the measured data (surface displacements and microseismicity) and the updated geological model of the prehistoric rockslide. From February 1960 up to 9 October 1963, the unstable mass behaved as a brittle-ductile 'mechanical system,' characterized by remarkable microseismicity as well as by considerable surface displacements (up to 4-5 m). Recorded microshocks were the result of progressive rock fracturing of distinct resisting stiff parts made up of intact rock (indentations, undulations, and rock bridges). The main resisting stiff part was a large rock indentation located at the NE extremity of the unstable mass that acted as a mechanical constraint during the whole 1960-1963 period, inducing a progressive rototranslation toward the NE. This large constraint failed in autumn 1960, when an overall slope failure took place, as emphasized by the occurrence of the large perimetrical crack in the upper slope. In this circumstance, the collapse was inhibited by a reblocking phenomenon of the unstable mass that had been previously destabilized by the first reservoir filling. Progressive failure of localized intact rock parts progressively propagated westwards as a consequence of the two further fillingdrawdown cycles of the reservoir (1962 and 1963). The characteristic brittle-ductile behavior of the Vajont landslide was made possible by the presence of a very thick (40-50 m) and highly deformable shear zone underlying the upper rigid rock mass (100-120 m thick).

show abstract

“…It should be noted that the slope reaching such velocities requires a sudden acceleration of the rock mass. Such cases have been observed in the well-known cases of Vajont, Italy in 1963 (Barla and Paronuzzi 2013), Loen in 1905and 1936and Tafjord in 1934(Lacasse and Nadim 2007, among others; with some Canadian examples in the Frank Slide in Alberta, Canada 1903 (Cruden and Martin 2007), and the Hope Slide, British Columbia, Canada 1963 (Bruce and Cruden 1977). Hermanns et al (2013b) and Oppikofer et al (2015) present a qualitative hazard and risk classification for large unstable rock slopes in Norway.…”

Section: Slope Instrumentation and Deformation Patternsmentioning

confidence: 91%

Development and application of a quantitative risk assessment to a very slow moving rock slope and potential sudden acceleration

et al. 2015

View full text Add to dashboard Cite

Development and application of a quantitative risk assessment to a very slow moving rock slope and potential sudden acceleration Abstract The benefits of quantitative risk assessments for landslide management have been discussed and illustrated in several publications. However, there still are some challenges in its application for low-probability, high-magnitude events. These challenges are associated with the difficulties in populating our models for risk calculations, which largely require the input of expert opinion. This paper presents a quantitative risk assessment to a very slow moving rock slope within a dam reservoir in the Province of British Columbia, Canada. The assessment is focused on the risk to the population in the vicinity of the dam and the populated areas downstream. Expert opinions quantified the slope failure probabilities in the order of 10 −3 to 10 −1 per year for the smallest failure scenario considered and less than 10 −6 for a failure of the entire slope. However, these estimations are associated with high levels of uncertainty. Our approach starts with the calculation and assessment of the magnitude and probability of the potential slope failure consequences, minimizing the uncertainties associated with estimated slope failure probabilities. Then, these consequences and failure probabilities are combined to obtain a measure of risk. The uncertainty associated with the slope failure probabilities is managed by the estimation of plausible ranges for these. The calculated risk levels are then presented as ranges of values and assessed against adopted evaluation criteria. The consequence and risk assessment of the rock slope suggest that the risk to the population exposed in the vicinity of the dam and populated areas downstream is under adequate control. The probability of large consequence scenarios is extremely low, in the order of 10 −7 chance of an event causing more than 100 fatalities. We propose an observational technique to assess changes in risk levels and decide when to update the risk management approach or deploy emergency measures. The technique is focused on the detection of changes in the slope deformation patterns that would indicate an increase in the potential failure volumes or an imminent failure. It can be considered an extension to the current early warning system in place, easy to implement and enhanced with the strength of the comprehensive analysis required for a quantitative risk assessment.Keywords Risk assessment . Landslide hazard . Rock slope . Consequence analysis Checkerboard Creek rock slope The Revelstoke Dam, part of a hydroelectric generation project on the Columbia River, has an installed capacity of 2,480 MW. A future expansion is being planned that would increase the capacity by another 500 MW (BC Hydro 2014). The dam, 5 km upstream of Revelstoke, British Columbia, comprises a 1,160-m-long earthfill dam that wraps around a 183-m-long concrete gravity dam and the concrete gravity spillway structure (Taylor and Lou 1983;Salmon 1988). Figure 2 shows the...

show abstract

The 1963 Vajont Landslide: 50th Anniversary

Cited by 63 publications

References 5 publications

Gravity-induced rock mass damage related to large en masse rockslides: Evidence from Vajont

Gravity-induced rock mass damage related to large en masse rockslides: Evidence from Vajont

Brittle and Ductile Behavior in Deep-Seated Landslides: Learning from the Vajont Experience

Development and application of a quantitative risk assessment to a very slow moving rock slope and potential sudden acceleration

Contact Info

Product

Resources

About