0000000000012265
AUTHOR
Alessandra Nocilla
showing 7 related works from this author
Role of particle characteristics in the compression behaviour of gap-graded sands
2019
Abstract The compression in gap-graded mixtures of sands with combined mineralogy has been investigated in recent research, focusing on the key factors that might imply the occurrence of convergent or non-convergent paths in compression (i.e., transitional or non-transitional behaviour). From previous work, the mineralogy of a matrix composed of larger grains seems to determine the possibility of the occurrence of transitional behaviour. Hence, if there is a strong and stiff matrix made of quartz sand particles, which are either larger than or at least of similar size to the other component, then non-convergent compression paths (i.e., transitional behaviour) are likely to occur. As a furth…
The Effects of Structure on the One Dimensional Compression Behaviour of a Porous Calcarenite
2019
Human settlements built on weak rock deposits are often characterized by instabilities or collapse that may involve the underground cavities and consequently the above buildings. Underground calcarenite quarries in Marsala have been involved in a number of collapses that have seriously damaged numerous buildings. Unfortunately proper engineering solutions have not yet been identified according to the different and special cases and to the properties of this structured material. In order to investigate structure effects on the behaviour of the porous calcarenite of Marsala, this paper presents a comparison between the one dimensional compression behaviour of the intact rock and of the same w…
Evaluation of cliff recession in the Valle dei Templi in Agrigento (Sicily)
2015
Abstract The sacral complex of the Valle dei Templi in Agrigento, added in the UNESCO Heritage Site List, stands over the crest of a rigid calcarenite cuesta, which overlies a layer of partially saturated (S = 6–12%) carbonate sand. In turn, the sand stratum lies on a thick stratum of clays. The environment is highly prone to landslides as highlighted by several previous studies that identify the undermining of slopes and the discontinuity pattern, occurred in the late Neotectonic phase, as causes of cliff failure. For wider and less exposed areas, where the undermining local instabilities can be present because of the specific morphology of the site, a recent research has proposed a new in…
Rock decay phenomena and collapse processes in the “Latomiae del Paradiso” in Syracuse (Sicily)
2014
The Latomiae (origin: Greek latomia, from laas, las stone plus –tomia tomy ) del Paradiso in Syracuse are Magna Graecia rock quarries, located in the coastal areas of Southern Italy and internationally renowned for their impressive environment. The few historical technical records do not help clarify the events that led to their current configuration since a series of instability phenomena occurred due to decay processes over time. Through a geotechnical back-analysis, this work highlights the failure phenomena, which may have led to the current configuration of the easterly side of the Latomiae del Paradiso. The back-analysis process was carried out by means of numerical modelling, support…
Measure of a limestone weathering degree using Laser Scanner.
2013
The weathering degree of the building materials and natural stones is generally quantified as the decrement of some mechanical features that can be measured experimentally by means of compressive tests or point load tests in the laboratory or Schmidt hammer tests carried out in situ. Such destructive or damaging tests are unacceptable in case of cultural heritage since even small amounts of damage must be avoided. This work shows a correlation between Schmidt hammer rebound values and the reflectivity that is detected by means of terrestrial scanner laser; therefore it allows assessing the weathering degree of buildings or stones in situ. The results demonstrate that such an investigation c…
Meccanismi di collasso nelle Latomie di Siracusa
2015
The aim of this work is to support, through geomechanical methods, the historical hypothesis proposed by the archaeologists according to which the Latomiae of Syracuse, ancient Greek quarries, were originally mainly developed underground. In order to reach this objective, the finite elements numerical modelling was applied. The input data were inferred from the geologic history, from different archaeological reports and from the geomechanical characterization both of the intact rock and of the rock mass. The study highlighted the geotechnical events which modified the shape and the safety conditions of these amazing ancient quarries over the centuries.
Terreni collassabili e processi di instabilità nella Valle dei Templi
2015
The sacral complex of the Valle dei Templi in Agrigento, included in the UNESCO Heritage Site List, stands over the crest of a rigid calcarenite cuesta, which overlies a layer of partially saturated carbonate sand. The environment is highly prone to landslides and the calcarenite stratum is often in limit equilibrium conditions. Toppling phenomena threaten some of the more relevant archaeological structures such as the Giunone's Temple, the Vulcano's Temple, the Santuario rupestre and the palaeochristian Necropolis. As highlighted by several previous studies, the instabilities and the recession of slopes have been caused by the undermining of slopes combined with the discontinuity pattern. …