Rock Falls

Математическое моделирование и оценка рисков камнепадов в программном комплексе RocFall для разработки мероприятий по инженерной защите Ф о м е н к о И. К. , Го р о б ц о в Д. Н. , Н о в г о р о д о в а М. А. , С и р о т к и н а О. Н. Р Г Г Р У и м е н и С е р г о О р д ж о н и к и д з е (М Г Р И) М Г У и м е н и М. В. Л о м о н о с о в а ООО « С о в р е м е н н ы е и з ы с к а т е л ь с к и е т е х н о л о г и и » М о с к в а 2 0 2 2 г .

Procesos de remoción en masa inducidos por el terremoto del 27F de 2010 en la franja costera de la Región del Biobío, RESUMEN Se estudian procesos de remoción en masa (PRM) detonados por el megaterremoto 8.8Mw del 27F 2010, en el litoral de Concepción, Región del Biobío, Chile. Se analiza la morfometría y se explican los factores de peligrosidad de 22 eventos. Los tipos de PRM identifi cados fueron: desprendimiento de roca y suelo, deslizamiento de roca, deslizamiento de suelo, extensión lateral de suelos y remoción en masa mixto. Se revela el fuerte peso de los factores locales como condicionantes de los PRM: pendientes topográfi cas, manejo de taludes, grado de saturación del suelo, características litológicas y tectónicas. Se concluye que la densidad de los PRM se incrementa hacia el epicentro, pero el número y tamaño de estos no es comparable con la magnitud del sismo; este aspecto estaría relacionado con las características del relieve y con la baja humedad del suelo, dado que el sismo ocurrió en verano (estación seca del clima mediterráneo).

In recent years, rock fall phenomena in Italy have received considerable attention for risk mitigation through in situ observations and experimental data. This paper reports the study conducted at Camaldoli Hill, in the urban area of Naples, and at Monte Pellegrino, Palermo, Italy. The rocks involved are volcanic Neapolitan yellow tuff (NYT) in the former area and dolomitic limestone in the latter. Both rocks, even though with different strength characteristics, have shown a significant tendency towards rock fragmentation during run out. This behavior was first investigated by comparing the volumes of removable blocks on the cliff faces (V 0 ) and fallen blocks on the slopes (V f ). It was assumed that the ratio V f /V 0 decreases with the distance (x f ) from the detachment area by an empirical law, which depends on a coefficient a, correlated with the geotechnical properties of the materials involved in the rock fall. Finally, this law was validated by observation of welldocumented natural rock falls (Palermo) and by in situ full-scale tests (Naples). From the engineering perspective, consideration of fragmentation processes in rock fall modeling provides a means for designing low-cost mitigation measures.

Indonesia's sustainable development system should be disaster-based mitigation. This research aims to analyze spatial geomorphology aspects, that identifies the potential and vulnerability of disaster that can be caused in Leato area (North Leato and southern Leato) at District Dumbo Raya of Gorontalo. Geomorphologically studied aspects using Geographic Information System (GIS) Global Mapper v12 and ArcGIS v10.3. Geomorphological analysis at the location of the research found that the area has coastal morphography up to the steep hills with an average height of 200-500 mdpl and morphometry of 8o to > 55o. Active morphostructure of tectonic activity which lasted relatively continuously since the Eocene - Early Miocene to Quarter, thus making it prone to high earthquake disaster that could become the trigger factor of a landslide. These influences resulted in the formation of geological structures including lithology breakthrough units Diorite Bone (Tmb) and Volcanic rocks Pinogu (TQpv) with a sturdy system that makes the weathering process run intensively on the body of the rock. Rock weathering conditions is a passive morphostructure of a landscape that can affect the cohesiveness of rocks so that some of them become rock fall type material avalanches. In terms of the morphology of the research area, the closure and use of land such as dryland and shrub farming to land and residential land transportation routes make the area not only vulnerable to landslides but also becomes vulnerable to a particularly adverse disaster on sustainable development in Gorontalo.

Keyword: geomorphology, gis, sustainable development, leato, rock fall landslides

Se estudian procesos de remoción en masa (PRM) detonados por el megaterremoto 8.8Mw del 27F 2010, en el litoral de Concepción, Región del Biobío, Chile. Se analiza la morfometría y se explican los factores de peligrosidad de 22 eventos. Los tipos de PRM identifi cados fueron: desprendimiento de roca y suelo, deslizamiento de roca, deslizamiento de suelo, extensión lateral de suelos y remoción en masa mixto. Se revela el fuerte peso de los factores locales como condicionantes de los PRM: pendientes topográfi cas, manejo de taludes, grado de saturación del suelo, características litológicas y tectónicas. Se concluye que la densidad de los PRM se incrementa hacia el epicentro, pero el número y tamaño de estos no es comparable con la magnitud del sismo; este aspecto estaría relacionado con las características del relieve y con la baja humedad del suelo, dado que el sismo ocurrió en verano (estación seca del clima mediterráneo).

Sovana, in the southern part of ancient Etruria (Tuscany, Central Italy) represents a centre of high historical and artistic values. Its Etruscan necropolis is particularly important, even compared to other centres of ancient Etruria, in view of the fact that all the major kinds of funerary architecture of the Tyrrhenian region are present: one of the best examples of Etruscan funerary work from the Hellenic period is represented by the "Tomba della Sirena", a tomb dating from the III century B.C. The Tomb is a large niche type monument shaped like an arch hewn from a single rock mass, and on its façade there is a carving of a double tailed mermaid, symbolizing the Sea Goddess and the Otherworld. A block of about 2 m 3 detached from the tomb façade in May 1999; the event determined a great emphasis on the problems of its restoring and its conservation. In order to examine the whole geological framework of the failure, a series of analyses, tests and studies have been carried out. First of all, the rock has been petrographically and geochemically characterised: based on the field and laboratory observations, the pyroclastic rock forming the "Tomba della Sirena" can be considered as belonging to the "Sovana Formation" in the Vulsinian complex (Roman Comagmatic Province). Afterwards, geomechanical investigations (inventory of the rock discontinuities, sampling and laboratory testing and back analysis) have been undertaken in order to understand the failure mechanisms and the preparatory and triggering factors. The pre-existing joint network and the intense weathering and loosening of the tuffs have been detected as the main causes of the failure. The multidisciplinary approach proved to be useful: in fact, besides giving a summary of the causes of the event, it helps to formulate convenient measures aimed to the restoration of the monument.

The global warming observed in recent decades and its future increase may affect permafrost distribution on highmountain faces with consequences for their stability. In this paper, we show that rock falls from high-alpine rock walls can be computed with a decimetre-resolution using lidar measurements. A laser scanner was used to create point clouds and triangulated irregular network models on the east face of the Tour Ronde at 3792 m asl (Mont Blanc massif). Comparison of the models realised from measurements of July 2005 and July 2006 enabled quantification of rock falls with reduced uncertainty. The volume of rock fall reached a total of 536 m 3 in the scanned area, which matches an erosion rate of 8.4 mm yr À1. This rate slightly higher to the ones reported in former studies enable to assume that this rock fall may be the consequence of the permafrost degradation in this rock face.