Frammenti di mosaico riportati su calcestruzzo:le interazioni con il supporto e il progetto di conservazione

COMPARISON OF CRIMSON FOUNTAINGRASS AND DISS FIBRES AS AGGREGATES FOR CEMENT MORTARS

The use of natural fibres in cement composites is an expanding research field as their use can improve the mechanical and thermal behavior of cement mortars and reduce their carbon footprint. In this paper two different wild grasses, i.e. Pennisetum Setaceum, also known as crimson fountaingrass, and Ampelodesmos Mauritanicus, also called diss, are used as source of natural fibres for cement mortars. The principal aim is to evaluate the possibility of using the more invasive crimson fountaingrass in place of diss inside cement based vegetable concrete. The two plants’ fibres have been characterized by means of electron microscopy, helium picnometry; moreover, the thermal conductivity of fibr…

The open metastable structure of a collapsible sand: fabric and bonding

This paper deals with the compositional and textural characteristics determining open metastable structures in the pleistocenic sand outcropping in the Agrigento district (Sicily). The aim of the study was to individuate the bonding types occurring between grains that could generate matric suction phenomena. The composition and microfabric were characterised by means of granulometry, porosimetry, permeability, optical and ESEM-EDS microscopy, thermogravimetry and XR diffractometry, electric conductivity, and ionic chromatography. The data thus acquired show that the skeleton of the sand is constituted mostly by bioclasts and microfossils, calcite and quartz monocrystalline grains. Moreover,…

I materiali lapidei naturali ed artificiali della Fontana Pretoria di Palermo

Progetto di recupero e conservazione della Villa Romana del Casale di Piazza Armerina. Indagini chimico fisiche sulle malte di allettamento e di finitura

Floor and wall mortars of archaeological site of Selinunte , Sicily

Il Teatro Greco -Romano di Taormina

The "Fossa della Garofala" in Palermo: a geological site rich in cultural heritage

The Fossa della Garofala is a short, narrow valley, enclosed by sub-vertical banks, which was carved out by the Kemonia creek on the calcarenitic table that makes up the bedrock of the Plain of Palermo. It forms the outermost hem of the Conca d’Oro landscape where, set in an urban area, geologic and geomorphologic features of value join historical cultural values dating from the Punic period to the XIX century. This combination places the entire area in one of the most significant, albeit little known, pages of history: the history of traditional suburban landscape. This rare synthesis of natural and anthropic landscapes offers the opportunity to create theme itineraries of great cultural a…

GIACOMA SERPOTTA AND STUCCOERS OF PALERMO: ASPECTS OF MATERIALS USED IN REFINED DECORATIVE ACTIVITY. THE PROCESSES OF DETERIORATION

Meccanismi di collasso nelle Latomie di Siracusa

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.

Petrography and decay of a marly limestone in the cloister of a medieval cathedral in Sicily

This paper deals with a significant process of decohesion of a marly limestone, taking place in the cloister of the medieval Cathedral of Cefalu, a pleasant town on the northern coast of Sicily. After desalination with deionised water and consolidation with ethyl silicate, the decay of the stone became faster. The aim of our study is to characterise the stony material and investigate the observed decay phenomena. The stone, that is a poor building material indeed, is characterised by means of petrographical, chemical and physical analyses on samples taken from the monument. Furthermore, experimental tests are performed in the laboratory in order to highlight the causes of incompatibility be…

Terreni collassabili e processi di instabilità nella Valle dei Templi

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. …

Valutazione dei parametri della resistenza al taglio delle discontinuità con l’ausilio del laser scanner

Effectiveness of some protective and self-cleaning treatments: a challenge for the conservation of temple G stone in Selinunte

Abstract The Temple G of the Archaeological Park of Selinunte (Italy), the largest in Europe, is one of the most impressive temples in the Magna Grecia. Today, it is completely destroyed due to a strong earthquake occurred in the Middle Ages. The used stone is a calcarenite coming from the ancient and renowned quarries of Cusa near the acropolis. This work comes from the today’s proposal of Temple G anastylosis. The goal of the work is to provide the results relating the protective effectiveness of three polymer formulations, appropriately selected, on stone samples taken from the “Capitello” quarry, part of “Cusa quarries”. The formulations functionality was deployed by adding TiO2 nanopar…

Assesment of the Conservation State of Stone Materials in Relation to the Level Environmental Pollution in the Conservation Place

The patina represents a superficial natural alteration of the constituting matter of the work of art. It emerges from the natural and usual stabilization process that the materials of the surface undergo because of the interaction with outdoor agents characterizing the surrounding environment. Besides, it is not linked to an obvious phenomenon of degradation that can be noticed through the change in the original colour of the matter. This is what we intend when we talk about biological patina usually generated by macro and/or micro-organic colonization (fungi, bacteria, alga) which contributes to surface bio-deterioration and thus lead to the formation of orange, red or even brown and dark …

Un approccio integrato allo studio dei terreni di fondazione e al restauro delle Carceri dei Penitenziati del complesso di Palazzo Steri a Palermo

Collapsible intact soil stabilisation using non-aqueous polymeric vehicle

Abstract This paper presents the results of an experimental study that had the goal of understanding the effects of treatment with polyethylene glycol (PEG)/nanolime mixtures on collapsible soil behaviour. In a previous study, the use of pure PEG offered a good improvement in the stability of collapsible soil, but the stabilisation effect only lasted for a limited time. To investigate the stabilisation potential of PEG/nanolime systems for collapsible sand, different mixtures were prepared at increasing nanolime weight ratios. The suitability of the stabilised soil was examined on the basis of collapsibility, oedometer, shear, and water vapour permeability tests, and through optical microsc…

The Effects of Structure on the One Dimensional Compression Behaviour of a Porous Calcarenite

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…

Mortars and Plasters under the Mosaics and the Wall Paintings of the Roman Villa at Piazza Armerina, Sicily

The Roman Villa at Piazza Armerina in Sicily, built in many successive steps over the 2nd and 3rd centuries A.D., is renowned all over the world for both the wealth and the refinement of its mosaic floors. In February 2007 the Regional Government of Sicily started a restoration project of the whole archaeological site. The systematic survey and study of all decorative elements highlighted the value of wall paintings, which until then were almost unknown except for casual approaches to specific problems of conservation, carried on without any relation to the far and away famous mosaics. This paper shows the results of a physical chemical investigation of the mortars used for both floors and …

Evaluation of cliff recession in the Valle dei Templi in Agrigento (Sicily)

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…

Studio dei dipinti murali nella chiesa del Monastero di Bodjani consacrata alla presentazione della Madonna al Tempio

Problems of soil and groundwater pollution in the disposal of “marble” slurries in NW Sicily

This work deals with disposal of slurries generated during the cutting and polishing processes of slabs of decorative sedimentary carbonate rocks in the north western Sicily. At present, they are used as fillers of dismantled quarries near the sawmills and, as a final step of reclamation, are covered with earth layers. In spite of such inexpensive solution, there is lack of knowledge about the composition of the waste. In order to assess if there is any threat for the environment and to suggest indications for alternative solutions, such as recycling or inactivation processes, the slurries were analysed by XR diffraction, simultaneous thermal analysis, ICP/MS, ionic chromatography, FTIR, UV…

Rock decay phenomena and collapse processes in the “Latomiae del Paradiso” in Syracuse (Sicily)

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…

Note preliminari sulla caratterizzazione di alcuni materiali

Osservazioni sulla successione stratigrafica degli stucchi della scuola di Giacomo Serpotta a Palermo

Characterization of hydraulic mortars from roman aqueducts of thermae (Sicily)

LA FONTANA PRETORIA IN PALERMO. Hic fons, cui similis nullus in orbe patet. Indagini chimico-petrografiche sui materiali lapidei e sul loro degrado

Problemi di conservazione delle camere ipogee in calcarenite nella Fossa della Garofala (Palermo)

La Fossa della Garofala è una stretta valle chiusa da pareti subverticali, incisa dal Torrente Kemonia nella placca calcarenitica che costituisce il sottosuolo di Palermo. Il valore storico monumentale della valle risiede, oltre che nella significatività geologica e geomorfologica del sito, anche nella presenza di cavità ipogeiche artificiali utilizzate dal periodo punico fino al XIX sec. La conservazione nel tempo di questo significativo patrimonio culturale è minacciata da fenomeni di dissesto sempre più frequenti. Il lavoro presenta una caratterizzazione geologica e geotecnica dell’ammasso calcarenitico e propone indirizzi progettuali per gli interventi di consolidamento.

Fossa della Garofala (Palermo): analisi del degrado dell'ipogeo del "Gazebo" e proposte per la conservazione e il recupero

Effectiveness of Preservative Treatments on Coloured Ruditic Building Stones

:  The dark grey Breccia di Billiemi and the Ammonitico Rosso of Piana degli Albanesi, two coloured stones widely used in monuments both outdoor and indoor in Sicily, undergo significant decay as effect of weathering: colour change and development of surface microcracks which affect not only the chromatic aspect but also the state of aggregation. In a previous study (Fracture and Failure of Natural Building Stones, 2006, Springer, Dordrecht, The Netherlands: 329), such effects were successfully reproduced on laboratory samples by means of artificial accelerated weathering and the different response of veins and grains to the ageing agents was related to the microstructure of stones. In this…

Il degrado degli stucchi serpottiano a Palermo in relazione alle condizioni ambientali di conservazione

This work is part of a demanding project, called “Progetto Serpotta”, performed since 2000 in cooperation with Soprintendenza Beni Culturali of Palermo. Aim of the project is the restoration of the unique stucco's artworks moulded by Giacomo Serpotta and his co-workers end of 17th -beginning of 18th century. This paper is focused on the problem of salt efflorescences, that are widely present in all of the churches and oratories restored in the framework of “Progetto Serpotta”. Particular attention is given to the relationship between the constitutive matter of the stuccoes, as analysed by means of both X ray diffractometry and optical microscopy, and the salts composition, as analysed by me…

A proposal for the preservation and use of the geosite and the cultural heritage of the "Fossa della Garofala" in Palermo

Giacomo Serpotta and the stuccoers of Palermo: aspects of materials used in refined decorative activity. The costitutive materials

Estudio comparativo de tratamientos de consolidaciòn. Aplicaciòn a rocas calcarenìticas y calizas

The paper deals with the effectiveness of different protective treatments on porous stones used in the architecture and monuments in Spain and Sicily.

I materiali lapidei naturali ed artificiali della Fontana Pretoria a Palermo

Floor and wall mortars of the archaeological site of Selinunte , Sicily

Characterization of stucco works by means of simultaneous thermal analysis

Problemi di Conservazione di un'opera di Land Art di straordinarie dimensioni: il Grande Cretto di Alberto Burri a Gibellina (TP)

This work deals with the conservation of one of the largest land art works in the world. It is a sort of white shroud laid on the ruins of the town of Gibellina, Sicily, after the tremendous earthquake of January 1968. The most significant aspects of the degradation phenomena observed on site are related to some faults in the construction, due to the prevailing of the artistic requirements over the good rules of concrete technology. Furthermore the guidelines for both a conservation intervention and the subsequent maintenance of the art work are also indicated.

The skill in materials selection and processing at the Serpotta's studio during the baroque period in Palermo

Calcestruzzi delle Aviorimesse per Idrovolanti di Pier Luigi Nervi a Marsala (1940-41). Composizione e Tessitura

Giacomo Serpotta and the stuccoers of Palermo: aspects of materials used in refined decorative activity. The processes of degradation

The sinter of the Fontana Pretoria in Palermo

Valutazione dello stato di conservazione dei materiali in relazione al grado di aggressività dell'ambiente nel quale sono posti in opera

Le aviorimesse di Pierluigi Nervi a Marsala: correlazioni tra le diverse modalità di esecuzione e lo stato di conservazione

This work deals with the composition and the state of conservation of the concrete of two hangars designed and built by Pier Luigi Nervi in 1940-1941. The interest in this project is related both to the use of on site prefabrication for so large structures (45x55 m plan) and to some peculiarities of the mix design, in particular the aggregate/binder ratio and the lithological composition of the aggregates. The study has been performed by means of X ray diffractometry, optical microscopy in trasmitted light on thin sections, ionic chromatography and carbonation tests. The twofold aim is to assess the conservation condition of concrete after 67 years of ageing in a marine spray environment an…

Natural and accelerated weathering of two coloured siclian building stones

Le calcareniti e le malte della Porta Nuova di Palermo

NATURAL AND ACCELERATED WEATHERING OF TWO COLOURED SICILIAN BUILDING STONES

The wall paintings of the Roman Villa at Piazza Armerina in Sicily

L'uso del Gesso nelle Costruzioni del Vallo di Mazara in Sicilia

Le murature del Baglio e del Palazzo Filangeri Cutò di Villafrati (PA): studio chimico petrografico delle malte

DEGRADATION OF STUCCO WORKS OF SERPOTTA SCHOOL IN PALERMO AS RELATED TO THE CONSERVATION ENVIRONMENTAL CONDITIONS

La caratterizzazione delle malte dell'acquedotto Cornelio di Termini Imerese

Un antico impianto irriguo da salvare

The lining of the ancient cisterns in the volcanic island of Pantelleria

The paper deals with different types of lining of ancient cistern in Pantelleria,analysed by means of petrographical, physical and chemical analises. In spite of the abundance of pozzolana in the volcanic island, Punics and Roman preferred to use cocciopesto mortars.

FORMULATION OF LIME MORTARS BASED ON NATURAL FIBERS AND WASTE MATERIALS FOR MORE SUSTAINABLE BUILDINGS

Nowadays sustainability is one of the main concept in building construction, both considering energy saving buildings and life cycle assessment of building materials. According to these considerations, in this work the use of recycled and waste materials to produce a binder and the use of a natural fiber as reinforcement are investigated to obtain a sustainable mortar. Particularly, lime is obtained by kilning waste marble slurry from marbles quarries in western Sicily; pozzolanic aggregate is obtained by grinding glass powder from urban waste collection; natural fibers come from a widespread grass: Ampelodesmos Mauritanicus also known as diss. Scanning electron microscopy and helium picnom…

Le malte idrauliche dell’Acquedotto Romano di Termini Imerese

Aim of this paper is the characterization of ancient hydraulic mortars from the roman water supply system of Thermae (I-II cent. A.D.), known as “Aqua Cornelia” and "Figurella" aqueducts, more than 10 kilometers long. Because of malfunctioning of the "Barratina" siphon, major changes in the original adduction system were realized in several steps. Mortar samples were taken from both channels lining materials and structural elements, in order to contribute to answer some questions about the construction phases of the aqueduct. The materials characterization was performed by means of XRD analysis, optical microscopy, microRaman spectroscopy and simultaneous thermal analysis. The latter is a u…

Measure of a limestone weathering degree using Laser Scanner.

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…

Petrographic and textural characteristics and mechanical behaviour of Sicilian calcarenites

Caratterizzazione dei residui di lavorazione di materiali lapidei di pregio, finalizzata ad un possibile recupero

La collezione di marmi d'epocanelle Vie dei Tesori dell'Università

Composizione, tessitura ed efficienza delle malte degli acquedotti Romani Cornelio e Figurella

Nell’ambito della conservazione dei beni culturali lo studio delle malte idrauliche a base di calce aerea rappresenta un tema di grande interesse per la complessità e la varietà dei materiali utilizzati e per l’importanza che hanno ri- vestito nella storia delle tecniche costruttive, grazie alle loro elevate prestazioni meccaniche e alla loro durabilità. L’Acquedotto Cornelio di Termini Imerese in Sicilia rappresenta un interes- sante esempio di costruzione idraulica, nella quale queste malte furono utiliz- zate sia per rivestire i condotti con strati impermeabilizzanti sia per conferire resistenza meccanica agli elementi strutturali. Un ulteriore elemento di interesse sta nella sua comples…

L'uso di tecniche di microanalisi strumentale per la caratterizzazione di malte storiche con proprietà idrauliche

Characterization of mortars from ancient and traditional water supply systems in Sicily

Long aged mortars from ancient hydraulic constructions of Sicily, i.e. the Roman aqueduct of Thermae and the Punic cisterns and traditional water supply systems in Pantelleria, have been characterised by means of XRD analysis, optical microscopy and simultaneous thermal analysis to correlate the hydraulic properties to the texture and to their different role in the construction, i.e. lining, covering, roofing and joint mortars. According to a procedure proposed in the literature all of the samples, but two air hardening ones, show high hydraulicity, which somehow can be related to the characteristics of aggregates.

IL TEATRO GRECO ROMANO DI TAORMINA. Note preliminari sulla caratterizzazione di alcuni materiali

Durability of calcarenitic hypogea in the underground cultural heritage of Palermo (Sicily)

The paper deals with the stability conditions of hypogea, several hundred m 2 wide, dating from the Punic period to the XIX century, dug out of the calcarenitic table that makes up the bedrock of the Plain of Palermo in the Fossa della Garofala. This work concerns the influence that the shape of the hypogea and the characteristics of the lithotypes wields on the instability and decay phenomena taking place, by mean of laboratory tests on the calcarenite and parametric numerical models. The comparison between the numerical models and the actual instability phenomena validated the use of the empirical formula of Hoeck to the mechanical characterization of complex structured rock-mass in soft …