When we are dealing whth partial or total interventions in restoration, often the design choices tend to substitute several elements (for example windows and doors, panelling, roofing,ect.) due to economic, cultural and functional choices, to meet norms, or when there is a level of deterioration which makess recuperation of the elementt impossible.

In substitution, alternatives can enhance the overall image of the building, and orient towards to choise of elements similar at least in forma and colour, or better yet, using similar material and type of finish as the original element.

However, often design tendencies are not so attentive to the original image and this can lead to unhappy choices, especially when evaluated with retrospect, some time after the restoration. Using a series of restorations made on historic and also modern works of architecture, documented with comparative images, we hope to show how even minimal substitution of elements "similar" but actually quite different from the original, can make reading of the entirety and details of the original work vain.

KEY-WORD: Building restorations, image conservation, windows, evaluation of interventions.

ln relation to practice of conservation the concept of duration is closely connected to the real efficacy of each treatment. In the present study some practical examples concerned conservation in archeological sites of Calabria, are useful to understand the meaning and the importance of duration. Moreover, in terms of valuations, the study underlines the difference between those treatments which are suggested by traditional methods and those which are founded upon scientific standards. In the first case the duration of treatment is verifiable only with time. No other verification is possible. In case of treatment founded upon scientific standards duration is always tested with experiments that would anticipate the final results.

KEY-WORDS: Archeological sites, Calabria, Time, Tradition, Scientific progress.

Time is a good parameter to know and verify the effectiveness and durability of conservative repair and reinforce of structures and materials, especially of ancient and historic buildings. This report concerns the repair of the de Grande Guglia of the Duomo in Milan, made by conte Ambrogio Nava in 1845, the architect who planned and supervised the works. He was firmly against the demolition and the rebuilding of the structure as well-known personalities supported. He used effective and economic techniques in order to obtain the conservation of the building. His repair was aimed to straighten and reinforce the structure and its materials subjected to continuous static and dynamic actions. The effectiveness of repair is largely demonstrated in the long run by its durability; in fact only a century later, another repair was required. The static condition and the state of conservation of the Grande Guglia was continuously under control in the following years with experimental investigations and monitoring.

KEY WORDS: building structure of the Duomo in Milan, conservation, durability of repair, monitoring.

Time-check in restoration planning tecnique is certainly a timely subject, not only during and after planning and realization process, but also in the theoretical debate about restoration discipline. The widespread applications of digital tecniques, both in the cataloguing system of historical built heritage (used as method of control) and time-checking operations about monuments, must not leave out of consideration the direct, ’tactile’, experience and knowledge of building materials.

Key words Time-check, restoration planning, cataloguing system.

Recent interventions of restoration of "Battistero di Novara" have showed as after thirty-five years the operation realized by Umberto Chierici has had numerous positive result in the field of the art’s documentation and, generally, of the conservation of the monument, but it has also generated situations of deep degradation. The building, during the restoration of the Seventies of century, has been subjected to a repair of the joints executed with a mortar loaded of carthy inert to reach an adequate coloration to the new image of masonry left at sight. On the intradoss of the circular chapels, moreover,. has been realized a coat with mortar of consistence similar to the cement. Analogously in the rectangular chapels has been found thc presence of earth on the intradoss of the vaults, that is due to the progressive impoverishment of the mortars employed in thc remaking and to the attack of superior vegetation. From the transmitted documents it is possible take notice of the absolute will, in that time, of well operate, but from the verification during thc actual works it has been certify how much that actions have leaded to situations of new crumbling. This contribution explains the degradations by produced by these interventions and of the choices effected in the actual restoration, that prefigures a program of future maintenance, that will keep under control the condition of the monument.

KEY-WORD: Baptistry. Novara. compatible, conservation, degradation, plaster, reintegration, restoration.

Since at least as early as the fourteenth century there have been numerous structural restorations of the cathedral of Lucca. In the period 1784 to 1786 there was a major project to consolidate the north transept, which is very well documented by written, iconographic and epigraphic sources. An analysis of the masonry has enabled us to determine precisely which parts of the masonry are eighteenth-century work as well as to identify the construction techniques and materials which were employed in the operation. Only a century after the completion of the restoration project structural problems developed which probably resulted from the choice of materials that were used. Comparing the recorded data from the masonry structures with the results from certain non-destructive analyses has allowed us to identify the construction phases with greater accuracy.

Key words: structural restoration - building techniques – construction materials.

In the field of restoration there are many possibilities of making mistakes. That`s because there are many conditions that play a meaning role and especially it is hard to describe in a scientific way their interaction. It is also difficult to describe the evolutions of the secondary conditions, such as weather conditions, interactions between different materials, and how they modify the materials used in the renovation of the building.This new complexity force us to change our way of elaborating data and setting up the project of the restoration, also exploiting new technologies (such as hypertext). In this way it is also possible to elaborate a "time test", and the result should be released through new technologies, such as WorldWideWeb

KEY WORDS: hypertextual elaboration, WorldWideWeb, release result.

The subject of "check in time" of preservative interventions on existing buildings sends back to the two ideas of durability and technological compatibility. The reading parameters of the former can be explicit through the control of the effectivness of restoration proceeding and through thc ability of technical elements and materials to maintain the requirements of functionality and reliability unchanged; the latter expresses a checking action of intervention techniques on the physical structure of the building.

The present paper aims to show an operative instrument turned to the "continuous knowledge" of the real conditions of the historical heritage (both property and single building). It’s an Integrated Informative System, based on registration and updating of data, which allows to store up all the basic information about the initial state of the physical object, about the dynamics in time of such state, about the nature of changes in time. The architecture of the system is variously mouldable according to the building object that is observed and it s organized to record, in a flexible way, the return information, which are filtered by the observation of the conservative and transformative procedures on the material, in order to check and steer the future strategies of intervention.

KEY-WORDS: Building restoration, conservation, informative system,

limestone made of minuscule nodules of a pale colour varying from grey to hazel. The cultivated layers are carbonatic interpolation in eocenic seams marls of Gassino formation. The negative characteristics of the stone is the presence of small cavities with marlic filling well noticeable. In the fresh rock this fault is not so evident because the filling as coherent aspect and a colour which very well match other components of the stone. The marlic filling . exposed to the air in presence of humidity looses coherence producing cavities of different sizes.

After describing in detail the phenomenon - never, clearly pointed out in literature - the author have analysed the quality of the stone considering biggest sizes used and counting the defects noticeable on the surface of a representative sample of architectural elements. Beside the , author have studied a case histories of different methodologies of intervention, going from the "non intervention", to doweling in the same stone material to stuccoing whit methods and materials different in time. For the most documented case the author make a of comparison ;,and evaluation of the results after a certain lapse of time.

Santa Maria del Giglio church was financed by Barbaro family, in particular by consul Antonio. Igtrian stone is the material more abundant and it forms principal architectonic structure with smooth slabs, colums, cornices sculptures and bas-reliefs.

Carrara marble is used only for statues of Barbaro family, located at bottom, I° order, and funeral monument dedicated to Antonio Barbaro, II° order, and the escutcheon located on the top at III°- order.

Afther the consolidation and protection of monument’s surface some measurements of colour and water absorption were carried out on selected areas. In order to compare the influence of water repellent substance on the colour change and on the water absorption some tests were carried out before and after the treatment. A further control was also carried out after four years.

Key- Word water repellent, water absorption, colorimetric measurements, pipe method

The calcium oxalate films are among the most important alteration phenomenon present on ’ stone material artefacts. A deep search into the specialised literature pointed out a high number of oxalate films recoveries. In some case the films were associated to the presence of organic substances, residue of the past treatments. The protective effect of oxalate films is discussed and correlated to the discussion about their origin and decay. One of the hypotheses is that organic compounds have oxidised and formed oxalic acid which is then mineralised as calcium oxalate and, ’ being very stable, can protect the stone surface. Further, the actual use of calcium oxalate as conservation treatment proposed by some Authors is reported and discussed. Key words: oxalate films, protection, stone materials.

The paper presents the results of tests based on comparation of different interventions used in the conservative treatment of architectural surfaces and on their real effectivness tested eight years later. The 1993 original tests have been effectuated with the collaboration of Istituto Centrale del Restauro in Rome during the rcstorntion of S. Andrea fuori Porta del Popolo stone face. The test, finalized to conservative intervention, compared different inorganic and organic protective and consolidants was oriented to knowledge of up date and historical protectives and consolidant response, as regard to reversibility, compatibility and duration,. After eight years some campioni were tested (pore size and volume distribution and SEM watching) to observe the real effectivness of different products applied. Tests showed the good result both of some alchialcosilossanic and inorganic protectives especially the latte di calce and pigments ones .

Key words Protective, consolidants, organic, inorganic, surfaces material autenticity, imagine conservation.

Gli interventi di tinteggiatura ed intonacatura sulle facciate da tempo sono al centro dell’interesse di restauratori, addetti ai lavori ed utenti. L’incidenza sui costi, ma anche sull’impatto ambientale dei rifacimenti di intere palazzate. hanno determinato in questi ultimi vent’anni una particolare attenzione non solo delle case produttrici, ma anche degli operatori (imprese edili, architetti, aoprintendenza.,) su questi temi.

Dal 1995, in seguito ad alcune esperienze maturate, a Genova, all’intemo delle Facolta’ di Architettura (Istituto di Scienze delle costruzioni) e di chimica (Istituto di chimica Industriale), con la Scuola Edile genovese ed il Servizio Estetica Urbana del Comune, è stata condotta una campagna di monitoraggio avente come oggetto la verifica degli interventi compiuti in questi ultimi decenni

Aim of this research is the evaluation of the effectiveness of the restoration works undertaken on the last decade as far as the consolidation and the surface treatment of the constituent stone materials are concerned. The work deals with some monuments in the area of Salento (South-Italy).

The research has been carried out by gathering together data getting from the archives of the Italian Ministry of Cultural Heritage (M.B.A.C.), the primary information from the operators and the survey of the present state of conservation of the monuments themselves.

Taking as a starting point the illustration of the specific case of the restoration of the Church of the Rosary (Chiesa del Rosario) in Lecce, the contribution of the reports on the building-site works is discussed. The examination of the present state of conservation shows how the scarcity and the poor quality of these records increases difficulty in evaluating the results of the works undertaken in the past. On the other hand, such an evaluation is complicated by the lack of in-situ checking methods as well as by the difficulty in matching lab results with the real performance of materials in work.

Key-word: South-Italy, monuments, "pietra leccese", official records of restoration, conservation.

The aim of this work is to verify the effects of a consolidation treatment made ten years ago with ethyl silicate on the sandstone utilised, together with other materials, in the Abbey of Santa Maria a Vezzolano, located in the Monferrato hills (northern Italy). In fact, the alteration forms observed in the stone show the inadequacy of the treatment. In order to verify the possible modifications determined on the stone material by the consolidation product, extensive mineralogical, petrographycal and physical determinations have been accomplished both on the sandstone from the church and from the quarry (as comparison). Moreover chemical analyses have been carried out in order to emphasise the presence of the amorphous silica as a consequence of the treatment. The results show an increase of the relative percentage of the mesoporosity (0,0037<r<150pm) and a consequent increase of the saturation index respect to the quarry material. This different behaviour can be a possible reason for the bad conditions of the conservation of the treated material.

Keywords: consolidation, ethyl silicate, sandstone

Some monuments of Ferrara were submitted to restoration carried out over a reriod from 20 to 10 years ago. the interventions were realized in different operative stages. About 20 years later the early restorations and 10 later the last one, in some cases macroscopic alterations were detected: abundant biological growth, detachment of stone fragments, colour changes of areas treated whid the organic substances in respect to untreated areas. Purpose of this apper is the control of the presence, after about 20 years, of some substances used in the restorations as well as their supsceptibility to biological growth.

Key-words: stone monuments, acril resin, silicone resin, treatments, ageing, biological growth.

We have analysed several stone-material samples which had been treated on the surface about twenty years ago with an acrylic polymer. As we don't dispose of data relative to the inventions, we chose enquire techniques in any case in a position to furnish indications on the state of the protective film and the material. The result indicate (i) that the product doesn't undergo significant alterations, (ii) the lacunas on the protective film are imputable to external action of weathering and to the physical actions (usury), which must be considered both significant for the evaluation of the interventions.

Key-words: conservation, acrylic polymers, polymer degradation, Istria stone, Carrara marble, Verona marble.

The Zisa building in Palermo (XII th century) suffered a very serious collapse in 1971. Some works of reconstruction and restoration were caarried out and ended in 1988. During these works the façade was protected by means of an acrylic resin which did not permit the normal transpiration of water from the walls.

A strong concentration of humidity threatened the preservation of frescoes and mosaics in the hall of the fontain. In 1999 a new intervention was necessary since, after a long inspection of the place, a peculiar cleaning of the façade was needed, removing the acrylic resin using a mixture of solvents tested in laboratory.

Key-words: Humidity, acrylic resin, solvent

COMPARISON AMONG DIFFERENT PATTERNS OF RVENTION USED FOR RECOVERY OF THE ARTIFICIAL STONES IN THE ARCHITEC OF EARLY 900 The current work intends to consider the elements of artificial stone as "historical works" fruits of ’ manual abilities and handicraft knowledge. There is also the necessity to understand the elements of artificial stone both in order to decode the sins which these objects have impressed and to preserve these signs. Making on the spot investigation in several buildings yard have been tested the stages of recovery interventions. Examing the manifacture has been verified the validity of preservation intervention; in some cases emerge the problems connected with the ineffectiveness of the repair. The major damages have mainly caused by maintenance interventions, whose result is sometimes disfiguring, so much to compromise the durability of the artificial stones and to modify its superficial processing and colour. This work intends to propose the use of the intervention technics available, taking into account some particular situations and considering to be impossible to Intervene on any building or architectonic element, the formation process of both isn’t know. By this contribution the results of some study cases, which have been here examined, will be returned.

Key-word: Restoration of artificia1 stone

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Gli edifici di Castelseprio, spesso ridotti a ruderi di pochi metri di altezza, si sono sempre trovati in uno stato di conservazione molto precario. Infatti, le murature sono costituite da ciottoli lapidei e laterizi con giunti di malta e di calce e sabbia con aggiunta di cocciopesto. Il clima, particolarmente piovoso, favorisce i fenomeni di erosione dei giunti di malta; inoltre la vegetazione spontanea, aggredisce in piu punti le murature. Gli interventi conservativi hanno visto dapprima ricostruzioni piu o meno estese con ciottoli e malta, necessarie anche per dare stabilità ai ruderi (anni ’50-’60); in seguito si è provveduto alla stesura di sigillature sulle creste dei muri (una sorta di wall capping), al fissaggio dei singoli ciottoli per impedire l’accesso dell’acqua, la disgregazione delle malte ed il crollo dei muri.

Nei primi interventi sono state utilizzate malte di varia composizione, anche cemeatizie; negli interventi successivi malte additivate da resine epossidiche o acril-siliconiche; negli interventi piu recenti malte dj calce e sabbia. In assenza di procedure codificate per la verifica degli interventi ’si può osservare che i prodotti utilizzati nelle malte hanno quasi sempre perso la loro funzionalià.

The wall capping system is widespread on archaelogical areas to avoid the penetration of the rain water into the core of the walls. Castelseprio, the archaelogical area near Varese (Northern Italy) shows a great number of walls as result of the destruction of churches and buildings. The restoration works involved the setting of new stones, the wall-capping using Portland cement, the sealing using organic resin. Scientific analyses detected the texture and composition of the materials and tested the present-day role. The role of wall capping is today ineffective and we observe a discontinuity between the mortar and the building stones. The discontinuity allows the penetration of the rain water, the growth of plants, the detachment of stone from the wall and the destruction of original mortars.

Parole chiave: archeologia, muratura, conservazione, resina epossidica, resina acrilica, Cemento Portland.

Key-words: archaeology; masonry; conservation, wall-capping; acrylic resin; epoxy resin; Portland cement.

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The scope of the present work is the development of an appropriate methodology for the long-term evaluation of consolidation interventions on site. Pilot scale consolidation treatments have taken place on the fossiliferous highly porous calcareous sandstone of the masonry and fortifications at the Medieval City of Rhodes. The performance evaluation of the consolidation materials has occurred in different time periods (3 months, 15 months and 28 months after the application), in order for a integrated evaluation of the consolidation treatment to be attained. The methods and techniques employed were the following:

From the results obtained at each different time period, the proper long-term performance evaluation of consolidation treatments may be concluded.

Key words: consolidation treatments on site, long-term performance evaluation, non-destructive techniques, micro-structural modifications.

Cà Michiel delle Colonne, a palace on the Grand Canal, Venice, was rebuilt in the middle of the seventeenth century over an old gothic edi6ce. In 1960 heavy and rigidifying work was undertaken on the building - work which profoundly altered its structure, increasing its hypostasis.

A number of cracks being found on many of the decorative surfaces, an investigation was conducted with the aim of discovering the cause of the instability.

It transpired that the system of construction adopted during the consolidation, tending as it did to rigidify the building in order to offset the greater vertical overloading, was incompatible with the margin of elasticity necessary to absorb dynamic stress and possible differential subsidence, typical of Venetian buildings.

From a study of the monitoring effected, the principal load-bearing structure - profoundly altered in a ,by-now irreversible manner, was proven to be stable in the presence of static loads, but might risk further plastic deformation in the event of stress from external forces; and in fact the 1976 earthquake caused serious damage to the more fragile structures, such as ceilings and decorations.

In consequence, preventative systems for the decorative surfaces, designed to limit the effects of impact or repeated concussion from external forces, were researched.

Key-word: Venice, Cà Michiel delle Colonne, consolidation, elasticity

In the doorway of Nonantola Abbey Church there is a XII century stone lintel. This architrave broke to four pieces after the earthquake in 1117 and in 1915 the Nonantola's Abbot strenghted it connecting the elements by iron bars. In this paper we analyse the reliability of this strengthening and the behaviour of the cast lead joints.

Key-Word: reliability, strengthening, cast lead joints.

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Since the early decades of 20th century reinforced concrete has been widely used even in restoring archaeological ruins. This has taken place in ancient Pompeii starting from the 1930s and has continued up to the 1980s. The new technique has widely been applied in the (re)building of roofs, which would usually be made wing a system named SAP, and now are often collapsing. In most cases reinforced concrete structures were meant to substitute former wooden roofs which had been built, as soon as ruins were excavated, according to the traces left by ancient, beams or tiles. Reinforced concrete elements were usually built adopting shapes and dimension of those wooden elements which were to be removed. After few decades, most of these roofs have. turned out to be seriously afflicted by heavy and spread deterioration owing not only to weather causes but especially to low quality of materials which were often used in post-war times.

A careful analysis has been carried out on a few significant cases (Vettii.House, Julia Felix House, Silver Wedding Anniversary House) observing the current state of deterioration, testing materials and elaborating calculations in order to evaluate the level of structual safety. Results show a wide range of possibilities: in a few cases demolition has been necessary, while in most cases preservation and restoring have been successfully achieved.

Key-words: Archaeological Sites /Pompeii / Roofs / Reinforced Concrete

The series of static reinforcement works the Basilica of S. Gaudenzio’s Dome in Novara has undergone so far has not yet come to an end. While new "fake" structures (iron reinforcement rings vithin the Dome) are being put in, one wonders about the value and effectiveness of those works: from Alessandro Antonelli’s, through those carried out in the 30’s and 40’s of the past century, up , to those completed in the last few months. The reinforcement works done after the Dome had been built and those conducted by Antonelli seem today the product of a sort of "transcendental subjectivity" that has nothing to do with the construction itself, being rather the product of personal choices closer to a culture of "doing" rather than "preserving", whose effectiveness is uncertain, which the discussions continued over a century give evidence of. Thus Antonelli’s work has been misinterpreted, and the règlement de sa pensèe that led him to design and build that architecture has ’not been considered by those designers who in the following years have been involved in reinforcement works, from Danusso’s extensive works - opposed by civil engineer Daverio several times over - to the two new steel reinforcement rings of today. This paper aims at determining, also in the light of the studies already carried out, whether the structural reinforcement works done up to now have been effective and compatible with materials and structures with respect to the construction static reinforcement, and verifying, as far as possible, their effectiveness in time.

Keywords: Restoration, structural rehabilitation, static reinforcement, S. Gaudenzio Dome.

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We wont to evaluate the actions of conservation made from 1964 until the 1993 on the limestone of Alghero (locally known as "massacà"), used in many building in town. Phenomena of degradation known before the actions of conservation: erosion from dissolution, pollution, mechanical effect of water and wind, thermical cycles.

Key-Word: Alghero, limestone, massacà.

The "Columbus House", placed near one of the most important gates of the Genoa old city in the ward of Porta Soprana, it s the only building survived after the waste of historic Borgo di Ponticello.

In 1992 at the celebrations of the fifth hundred years of discovery of America, was recovered the famous Italian seaman’s house and the surrounding area by the Soprintendenza per i Beni Ambientali ed Architettonici della Liguria. After ten years the building shows a lot of problems about structure and materials, that it is impossible to visit it completely. Some propitious coincidences, for example a lot of time to use, the house uninhabited and the affect that people have to this house, permitted to make a complete previous diagnosis and the total contribution of all subjects. Beside the researches have permitted to value the strength of the choices made in the previous agency with particular attention about materials used in connection with the durability of agency.

KEY-WORD Columbus House, diagnosis, restoring, analysis, materials.

An analysis of the materials and technics employed in fillings is accried on relating two different projects realized in culturally comparable periods (the 80s and contemporaneous works) for St. Peter’s in Vatican and St. Peter’s Tempietto in Montorio. Beyond the technical aspects of finished works, the different risults concerning durability and the possible preservation of the accomplished laster parts ar pointed out. At a first stage, for both monuments the filling works were carried on using a mortar based on cement with travertine powder, adding a syntetic additive for the facade of St. Peter’s in Vatican. These works originated different results in time: as for the former monument they underwent a cromatic, possibly chemical, alteration while this phenomenon did not take place for the latter. In the present projects they have chosen traditional types of mortrs ’for the mixture of the filling works but, they have decided to keep, as much as possible, the preexistent,fillings for the Tempietto whereas all the cement stuccoes of St. Peter’s in Vatican have been cast off and the strong chromatic contrast they produced on this facade.

Key-words Restoration, maintenance. fillings, material, research technics.

Recent restorations of the Chieri s Arch – completed at the beginning of the Eighties – had been put in action to break off a progressive degradation, primed also from atmospheric pollution, caused by the presence of the traffic of vehicle below the monumental barrel-vault. The interventions mainly had looked at the elimination of the plasters where strongly degraded and their reintegration with mortars apparently compatible, but of not suitable consistence. The actual situation shows a considerable effect of "alveolarization" and progressive pulverization of the plaster of restoration, involving also the portions of original historical matter. The non homogeneity of degradation result particularly evident. The time proof reveals therefore significant, because, in the arch of a period ’of twenty years, not only it has returned to the conditions before restoration, but the intervention has primed further process of crumbling, prejudicing also the continuity between support and plaster. The report will show, trough the analysis of sources and of found data the verification of the intervention effected and a program of conservation of the architectural object.

KEY-WORD Arch, Chieri, compatible, conservation, degradation, plaster, reintegration, restoration.

EVALUATION OF INTERVENTION RESULTS IN THE RE-USED PRE-INDUSTRIAL BUILDINGS

KEY-WORDS: re-use, pre-industrial building, flat-cost, management-cost

Since the second half of the XX century, the industrial development has been supplyng the building trade with a line of products with a basis of organic resins, often applied on stucco and plaster surfaces for "restoration".
Through the stuccoes in the church of s. Maria del Carmine in Milan it has been possible to measure, by scientific checks that have identified the used products, the irreversible deterioration caused by the application of these products.

Key-Word: Plaster, stucco, moulding

The choice of the technique and the materials to be adopted – whose goal is to maintain and perpetuate the structural and material values of the original works - should be compatible with the -characteristics of the items that have to be consolidated.

Though the trend nowadays is to replace the damaged portions with prostheses of solid or laminar wood of the same species as the original structure, so as to ensure better compatibility between the existing elements and the new ones, a different method has also been used widely since the second half of the seventies. It consisted of replacing the damaged wooden parts - no longer able to perform their structural functions - with epoxy micro-concrete prostheses made integral with the rest of the structure by means of fibreglass reinforced plastic or steel bars, embedded in the micro-concrete and glued to the existing wooden structure with epoxy based adhesives.

The effectiveness of this intervention essentially depends on the degree of mutual collaboration established between the wood and the prosthesis by the glue applied between the prosthesis and the wood and by the bar/wood connection.

As mentioned above, the initial interventions of this type date back to about twenty years ago. It was therefore deemed of interest to identify a non-destructive testing method that might provide indications as to the current state of preservation of such interventions.

This report describes the initial results obtained from laboratory tests and the subsequent in situ tcsts conducted on the Farnese Theatre in Parma by means of instruments exploiting the X-ray technology which has been found particularly useful for these purposes.

Key-Word: epoxy micro-concrete prostheses, non-destructive tests, connection, X-rays, state of preservation.

L’evento del crollo parziale del Campanile, colpito da un fulmine nel maggio del 1991, ha drammaticamente evidenziato le conseguenze della scarsa disponibilità di risorse da destinare allo studio e al controllo della resistenza di queste particolari tipologie strutturali.

Il monumento, che per la sua immagine forte, storicizzata, spiccando sugli edifici circostanti, è stato nel tempo punto di riferimento nella vita cittadina, dopo i1 collasso si presentava mutilo su gran parte dei fronti nord ed est.

Per la macroscopica lacerazione avvenuta è apparsa subito indiscutibile la necessità di dare all’opera una riconfigurazione architettonica dell’insieme, intervenendo su di essa per salvarla da uno stato di assoluta precarietà.

Il campanile, strutturato in un unica canna muraria controventata dagli archi rampanti delle scale e dai solai lignei al piano dei vari ordini, presenta un basamento di epoca medievale ed una sovrapposizione di due ordini realizzata nel Settecento. Il superamento delle difficili problematiche connesse alla particolare tipologia strutturale e all’entità dei danni ha reso necessario un approccio metodologico interdisciplinare nello sviluppo de11e indagini diagnostiche finalizzate a1 restauro che, partendo dall’accurato rilievo, hanno riguardato i terreni di fondazione, lo stato di conservazione dei materiali e il comportamento strutturale.

A distanza di alcuni anni dall’ultimazione degli interventi di consolidamento e ricostruzione, è stata condotta una valutazione delle procedure di intervento adottate. A ta1 fine è stato predisposto l’aggiornamento dei modelli di calcolo precedentemente utilizzati, sia in via teorica che sperimentale, in modo da valutare il miglioramento del comportamento della struttura al termine degli interventi.

The following observation are about the utilization of reinforced concrete integration,seams and injections in consolidation projects of historic wans; from 1960 to 1980 they were considered quite satisfactory but unfortunately time (as we can see in two specific sicilian examples that we chose) has shown that these interverntions don't last as long as they should and some other king of intervention is soon needed. They can then be considered as a contribution to a better strategy that focuses on a precise diagnostics and a more specific and long-lasting laboratory test.

Key-Word: Test, compatibility, de-restoration

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This paper reports on innovative method in repairing vault and arched roof of masonry buildings.

According to the three main structural criteria, strength, stiffness and stability, the structure must be strong,’, enough to carry loads, it must not to deflect unduly and it must not develop large unstable displacements. In order to preserve an arch (or a vault, whose ribs behave like an arch) it’s important to avoid the loading (self- weight, wind, earthquake) cause failure to occur by fracture of the material, and it’s necessary to prevent cracks from causing unstable mechanism of collapse (formation of a four-hinge arch). This is possible by joining UPN steel shapes to wall and vault ribs. Steel elements increase the rib resistant section, provide a connection between opposite walls, and counteract the vault thrusts (which is very useful to improve the building seismic resistance); besides they maintain the arch stone voussoirs compressed one each other, preventing them from sliding.

This repair technique was tried for the first time ten years ago during the restoration of S.Salvatore Maggiore Abbey in Concerviano. From then on it proved effective, above all on the occasion of the 1997 earthquake.

Key-Words: vault, arch, building restoration, structural repair and maintenance

Through a sampling of buildings retained meaningful both in base to the knowledge of the technological characteristics, that of the history of the interventions effected in the past - through a statistic elaboration of the picked results on the field - the model of departure has been defined.

The modeling of a method in degree to correct in operation middle-normal values of the specificity of the case in examination, has conferred to the study semiprobabilistic characteristics, such to mediate the appeals of theory (to build the model and to elaborate the picked data on the field) with those of experimentation.

The low dispersion of the picked data makes to retain that the method, through a suitable setting of the corrective coefficients that make it esportable to whatever reality and situation, can constitute a reliable tool for the planning of interventions of maintenance, especially in the circle of a plan that integrates strategies of different characters.

KEY-WORDS Reliability -- Maintenance – Temporal thresholds – Building components

La relazione si propone di riferire sui risultati di uno studio condotto nell’arco degli ultimi 12 anni sull’affidabilità di alcuni degli elementi edilizi costituenti l’involucro esterno.

Tale studio, in particolare, aveva l’intento di mettere a punto una metodologia di valutazione delle soglie temporali alle quali prevedere interventi manutentivi di diverso tipo e di graduale intensità.

Attraverso una campionatura di edifici ritenuti significativi sia in base alla conoscenza delle caratteristiche tecnologiche, che della storia degli interventi effettuati nel passato, si è pervenuti - attraverso una elaborazione statistica delle risultanze raccolte sul campo - a definire il modello di partenza, tale da costituire l’assieme di valori "medio-normali" di riferimento.

La modellizzazione di un metodo in grado di correggere detti valori "medio-normali" in funzione della specificità del caso in esame, ha conferito allo studio caratteristiche semiprobabilistiche, tali da mediare le istanze di natura teorica (per costruire il modello e per elaborare i dati raccolti sul campo) con quelli di natura sperimentale.

La bassa dispersione dei dati raccolti fa ritenere che il metodo, attraverso una adeguata taratura dei coefficienti correttivi che lo rendono esportabile a qualunque realtà e situazione, possa costituire un attendibile strumento per la programmazione di interventi di manutenzione, soprattutto nell’ambito di un piano che integri strategie di carattere strettamente predittivo con altre mirate soprattutto alla manutenzione secondo condizione.

The comparison between two churches similar in structure and period of construction leads to compare also the different solutions attempted to solve similar structural problems.

Santa Maria Assunta of Esine (BS) and Santa Maria of Nembro (BG) were constructed at tbe end of the XV century, correspond to the same type of building, the "pieve rustica", and have similar structural problems. Interventions supported by documents took place in the same periods: the ’60s and the ’90s of this century, and it is possible to compare them.

So we hope there will and more and more documentation of restorations in the future.

The propose of this article is how to get a correct sense in conservation research for a correlated effect of the use space in its environment s complexity, in its physical remaining and in its effective message preserving in time. The research work tries to point to the question regarding special saljuqide masonry in its original criteria construction in comparison of incorrect restorations after nine centuries years. In other words, it tries to makes up the different approaches, which are related to an existent building, so that indicates how it must be studied in term of territorial, geological, environmental approaches for restoration, in front of only physical direct operation, then destruction instead of the aim "Conservation". The discussion will be aimed how to get a simple scientific orientation for a correct conservation’s attempt, by a glancing at the time, being under verifying.

Key words: Conservation, Enviroment. Time, History, Caravaaserai, Quaat & Territory

The phases of the immediate "after restoration" are compared with the state of the present deterioration of three monuments. The restorations have been made in different times and with different techniques.

The comparison is executed considering the geographical location, the local microclimate and the level the environmental pollution.

Key-Word: maintenance, marmorino, washing away.

In 1997-98 SS.Pietro e Paolo's church has been restaured using for consolidation epoxy and acril-siliconic resin. In this study are describe the actual situation and are verified the comportment of stone materials and polymers employed.

Key-Word: conservation, stone materials, diagnostic, Selvatico

The Ninfeo of Genazzano, an important renaissance building, has been restored several times, during the XX century. Recent studies, carried out in the last years, based on structural survey, archive documents, mortar analysis, revealed the existance of two different construction, phases. Furthermore the abundant documents, concerning three conservation campaigns (1916-’18; 1970-’71; 1975-’76), allowed the identification and localization of the majority of the conservation

work. On the whole we had three different approaches:

Keywords: Genazzano, ninfeo; mortar; analysis; consolidation; cement grout; nailing; capping.