Analisi numerica dei processi di instabilità in cave sotterranee a Marsala (Sicilia occidentale)

Research output: Contribution to conferenceOther

Abstract

[automatically translated] The presence of extensive underground caveali systems, used in the last century for the extraction of material of construction in different contexts of the Italian territory, frequently determines situations of danger for the man-made environment, due to the development of processes of instability, that they can propagate upwards, until reaching the surface. Especially in cases where the historical memory of the presence and extent of underground caves has been lost, the urban development of population centers in recent decades may have determined the construction of housing and infrastructure above, or in the immediate vicinity of areas affected by complex cave systems. The territory of Marsala, in western Sicily, is characterized by a number of quarries for the extraction of the local calcareous rock, realized at depths varying from a few meters to about 15 m, on one level or on two levels, following the excavation technique in tunnels and pillars. After the cessation of mining, quarries have been abandoned and has inevitably started a process of decay of the physical and mechanical properties of the rock mass, which often resulted in the occurrence of instability in the underground. These phenomena, documented for the study area since the 1960s, consist essentially of collapse and deformation of the time and of the pillars of the underground rooms. In most situations, they are propagated upwards until reaching the topographic surface, with formation of subsidences which have also involved urbanized areas, producing significant damage. The last event took place in November 2013 and is presented in detail in another contribution of this conference. This paper describes the numerical 2D and 3D finite element analysis, performed on an interesting case study took place in June 2011 in the east of the city of Marsala, it produced instability in an underground quarry, and that caused damage to a school building. The availability of the complete survey of the underground quarry, performed some years before the sinking, in conjunction with specific geological and structural projections within the underground environments, they have allowed the execution of back analysis for the understanding of failure mechanisms and the identification the factors responsible for the genetic mechanisms of subsidence. In particular,
Original languageItalian
Pages39-39
Number of pages1
Publication statusPublished - 2014

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