Built Heritage: Monitoring Conservation Management

The contribution aims to deepen the study of the rural architectures in Campi Flegrei, with particular reference to the territorial area of Pozzuoli. Country houses, manor houses in the countryside, agricultural and lookout towers, rural outbuildings, farms born on archaeological remains, are the components of a rich architectural heritage strewn over agricultural land of Campi Flegrei; a heritage not yet fully known and cataloged, which pours in a state of apparent abandonment and constitutes an irreproducible repertoire of building traditions, materials and local techniques of undeniable interest. The study, which uses the results of a research, started by a group of scholars of the “Federico II” and funded by Regione Campania for the biennium 2004–2006, is characterized by an interdisciplinary approach, and will address (1) the relationship with the landscape of these settlements, (2) the reuse of ancient and existing buildings highlighting the continuity of use, (3) the technical-constructive and typological aspects and more specifically the architectural and materials ones. Two illustrative case-studies will be chosen, detailed through a careful graphic and stratigraphic relief, as well as through diagnostic surveys: the first one, relative to the area of Via Campana, which consists of a farm built on Roman remains witnessed by the presence of a nymphaeum in opus reticolatum, and the second one related to a home-farm, with a more complex plant, arose ex novo in the eighteenth century for the production of wine. In both cases will be highlighted the recurring conservative critical and the mechanisms of degradation and damage, aimed to the detection of correct methods for the conservation of this ‘fragile’ heritage.

The paper discusses the results of a recent research focussed on the formulation of criteria of landscape and architectural compatibility to set up Guidelines to achieve eco-efficiency and install renewable energy source applications for domestic or agricultural use in the rehabilitation of traditional rural buildings within the World Heritage Property of Cinque Terre, Porto Venere and the Islands. The research was commissioned by the Regional Directorate of Liguria to the Universities of Genoa and Pavia and faces a new challenge for this type of sites due to the highly sensitive landscape and heritage values in place. Two factors oriented the research: a continuous passage of scale, from the territorial level to building detail and the continuous exchange among specialists within a trans-disciplinary team. The results of theoretical models of calculation of energetic behaviour and requirements applied by experts in Building Physics have been compared with the evaluation of the actual state of conservation of the buildings, with the local conditions of weather and sun exposure, with the data on relative climatology and on superficial and profound geology, with the possible energetic exigencies and with the reasons for heritage preservation and protection so as to select the possible solutions able to respond to all identified needs.

Since 2010 the Authors have been involved, on behalf of your department, in different tasks of the multidisciplinary project “Sustainable Social Economic and Environmental Revitalization of the historic core Multan City”, financed by funds from the Pakistani-Italian Debt for Development Swap Agreement and governed by a Consultancy Services Agreement signed between the Foundation Polytechnic of Milan and the Ministry of Housing and Works of the Islamic Republic of Pakistan. Multan, one of the oldest inhabited cities in the Asian subcontinent and the sixth largest within the boundaries of Pakistan, is a city in the Punjab Province of Pakistan and capital of Multan District with a population of over 3.8 million. The general objective of the project is the promotion of the old town of Multan by valorizing its historical, architectural and cultural heritage. The proposed program aims to develop a pilot model in conservation by urban renewal and infrastructure improvement accepting culture and history as common human heritage and as tool to development based on approach of global and local citizen participation and public and private partnerships. Specifically, the Authors have worked on the tasks of the guidelines for the preservation of historic buildings within the walled city and Musafar Khana Complex at the Musa Pak Complex preservation project, including the Pakistan Italia Resource Centre design. The experiment, with complex objectives and focused on an urban scale and not on single buildings, in fact allowed to make some reflections about the preservation of cultural heritage in developing countries, despite the differences of cultural contexts.

In 1979 a piece of terra-cotta fell from a 1912 residential building at 115th street and Broadway in New York City and killed Grace Gold, a student from a local college. The Department of Buildings became increasingly concerned about the general aging of the city building stock and the overall lack of maintenance. A city law (Local Law 10/80) was passed soon after that dramatic event: it imposed a requirement on building owners to file a report on the structural soundness of their building facades every five years. Since then, the law has evolved to become increasingly strict in terms of procedures for the inspections and liability for owners, architects and engineers. Currently about 12,000 buildings are affected by the law. The building facades can be placed in three categories based on the severity of the conditions observed during the examination: Safe, Safe with Repair and Maintenance Program (SWARMP) and Unsafe. Defects in the “unsafe” category are supposed to be repaired within 30 days, unless the Buildings Department grants an extension, which typically requires that temporary pedestrian protection must remain in place until the repair is completed. SWARMP conditions must be repaired within the next five-year cycle. Although it is true that sometimes heavy and useless interventions were carried out in the name of public safety, the continuous monitoring and the subsequent repairs have helped to preserve the integrity of many building facades, including those of landmark buildings. Ultimately it has been positively welcomed also by building owners who, after initially lamenting additional costs for the inspections and mandatory repairs, have seen an advantage in doing minor preventative maintenance as opposed to drastic and expensive once-in-30-years restorations. The paper will present the main provisions and requirements of the law, illustrate its evolution, and discuss the consequences for the physical preservation of facades by showing some case studies.

The policies and strategies put in place in 2001 for the requalification of the architectural heritage of the company town of Carbonia, and for the recovery of the “Great Mine of Serbariu” (that won the

Landscape Award of the Council of Europe in

2010–2011), was based on a close collaboration between a multidisciplinary team of the University of Cagliari and the municipal administration of Carbonia. “The Handbook for the recovery”, whose construction is still underway, fits this framework and coincides with an operational tool that regulates action on the built heritage. It does not provide a catalogue of standardized solutions, but merely defines a knowledge base to guide the designers towards the recognition of the buildings’ invariant aspects and towards the understanding of the original architectural expression.

The historic trails form a very interesting architectonic and cultural linear system: not only the traces, but also the road works (walls, bridges, tunnels, drain wells, etc.), the connected buildings (churches, chapels, fortifications, custom-houses, mills, mines, etc.) rose out of ancient religious, military, commercial or industrial functions with a relationship between villages, towns, landscapes. Leaving out the more ancient trails (roman and medieval roads) with a lot of archaeological importance, there are in Italy many XVIII–XIX century roads now transformed or abandoned and decayed. These could be used now as trekking, cultural and museal resources, but it is necessary to preserve and conserve this heritage with specific inventories, analysis and restoration projects. The paper illustrates some recent studies and plans with guidelines for evaluating, preserving, rehabilitating, restoring and managing the Lombardy historic system trail. Particularly the goals of this paper are to: Describe the historic roads inventory that the Politecnico of Milan, connected with Lombardy Region Forestry Agency, made, comparing XIX century military maps with current maps to understand the permanence of the itineraries. Present the analysis and survey work made in some Lombardy areas to check the conservation levels of the inventoried roads and the architectural and landscape features connected to them. Show some detailed surveys of historic road segments analyzing materials, building techniques, decay problems and transformations to define conservation and rehabilitation treatments. Explain the Lombardy historic roads GIS set to organize and join all the gathered and surveyed data and to manage them in the future.

In all the fields of restoration, from the artistic to the architectural one, the principle of minimum intervention is always mandatory: no work is allowed if not effectively needed for the perpetuation of the cultural heritage to the future generations. Within the architectural restoration interventions, this approach should be applied also to the structural ones, but often this doesn’t happen, in part for safety’s sake, in part for the cultural unpreparedness of some technical designers, who work indistinctively on new and old buildings. Increasing the knowledge and the understanding of the ancient monuments structural behaviour is the only method to decrease the uncertainties and in consequence to minimize the interventions, whose effective necessity has to be proven, in line with the theoretical requests. In step with this, the structural monitoring, with its different approaches, represents an important mean to increase this knowledge, investigating what happened to the structure in the past, understanding its present evolution and also controlling it in the future. The aim of this paper is therefore to inspect the role of structural monitoring in the knowledge and also in the conservation process of the built historical heritage, bearing in mind that knowledge and conservation should always go hand in hand.

Cracks are a major issue in the field of cultural heritage. In order to evaluate the significance of a crack, a long term monitoring of the damaged region is required. However, there is a lack of easy to operate tools for such monitoring measures. Therefore, new or existing methods for other applications have to be optimised for cultural heritage investigation. The paper describes the application of such crack observation methods on a historic concrete sculpture. Beside conventional methods, like mapping by hand and ultrasonic depth profiling, a novel tracking system is presented. Furthermore, the suitability of active thermography for the investigation of cracks was investigated. The results show promising prospects for these non-destructive techniques.

The generalized increase in noise and vibration emissions in the vicinity of structurally sensitive buildings is a factor of degradation of monuments and built heritage. In extreme conditions those emissions may also pose a risk to life as the result of collapse of constructive and decorative elements. In this paper we present a case study, where we proceeded to vibration monitoring by assessing the impact of excessive noise levels and vibrations on the surroundings and the interior of Monastery of Santa Clara-a-Velha (Coimbra, Portugal).

The Basilica of Santa Maria Gloriosa dei Frari was involved by dangerous horizontal and vertical movements of the bell-tower which induced severe cracks on the supporting structures of the Basilica. After the installation of provisional reinforcing systems, two main works were carried out in order to decrease the movements of the bell-tower and the openings of the cracks in the structures of the Basilica. At first, the consolidation of the soil foundation of the bell-tower was carried out by using the soil-fracturing technique; then a structural joint was created between the bell-tower and the adjacent structures of the Basilica. All the phases of the interventions, which were completed in December 2008, were carefully checked by using an automatic monitoring system able to give in real time precious information on the movements of the structures. This monitoring system, which includes a direct pendulum, several crack-gauges and livellometric measures, is still active and it will continue to operate in the future for a log-term control of the behaviour of the Basilica after the consolidation works. This type of monitoring is able to guarantee the safety of the structure during the works and can be considered as a design tool which allows, through the application of the observational method, to change during the works the design of the strengthening interventions taking into account the real behaviour of the structure.

Historic buildings rarely show themselves as they were to their origins, with the same shape and materials The signs of local repairs, but also modifications and expansions are reported on the building as indelible scars that need to be recognized and interpreted. It is important to read these signs, especially in load-bearing structures. One of the first steps for this study is the correct analysis and classification of the quality of the load-bearing masonry, with the help of both an accurate visual inspection and a diagnostic investigation. The classification of the correct masonry typology is now requested also by the last Italian seismic code (NTC 14.01.2008 and annexes), that supplies different mechanical parameters useful for the structural evaluation, according to the masonry typology. Serious mistakes can be made in the structural evaluation of a historic stone masonry if the definition of the masonry typology is incorrect. In several cases there is no coincidence between the visible masonry texture and the transversal cross section. There are different levels of approaching this matter, starting from a description based on a visual inspection, that can be carried out with the help of a template, till the parameters definition achieved by in situ investigation tests. Several parameters may be important to be determined in order to evaluate properly a masonry. The results of the experimental investigation (with a comparison between NDT and MDT tests) and a methodology for the analysis of the masonry quality, according to the standard suggestions for the knowledge levels, reporting all the pros and cons of all methods, are here presented.

The paper describes the experimental procedures applied to assess the structural condition and the seismic vulnerability of the Gabbia tower in Mantua, after the seismic sequence of Spring 2012. An extensive research program was planned and carried out to support the future preservation actions, including direct survey and historic and documentary research, several experimental and numerical tasks. The paper summarizes the results provided by a wide multi-disciplinary investigation and especially focuses on the key role of direct local inspection and dynamic testing in the seismic assessment of the historic building.

The ancient walls surrounding the historic center of Ferrara for 9 km almost uninterrupted, create one of the most impressive defensive systems of the Middle Ages and the Renaissance. The earthquakes of May 2012 increased the instability of the bastion of “Sant’Antonio” in the south walls, in fact, existing lesions are evidently grown. In order to preserve this historical and artistic heritage a complex monitoring system, based on the integration of various surveying techniques was realized. At the base of the structure a high precision geometric leveling network has been materialized to determine the vertical component of displacements, indeed on the top have been set up targets to determine by total station the planimetric component of displacements. Finally, we used TLS (Terrestrial Laser Scanner) to rate global variations of wall shape and some crack gauges to monitoring the main lesions. From the first repetitions of surveying with the described techniques, we remark a progressive increase of the framework deformation and an interesting agreement of the results.

During the earthquake emergency which involved Emilia Romagna Region (Italy) since 20th of May 2012, the Italian Civil Protection Department (DPC) undertook, with prevention purposes, an extensive survey on the ordinary buildings of the historic centre of the town of Ferrara, around 30 km far from the epicentral area. The activity, carried out in close cooperation with local authorities, was aimed at enhancing the seismic emergency response of the town in case of a possible further seismic event, as well as collecting technical information on the structural characteristics of the buildings, to be elaborated and hence used for further prevention purposes. Innovative element of the project was the use of two joint survey operative tools, consisting of the AeDES form used by DPC for post-earthquake usability assessments (2007) and AS form (specific for historical building blocks) which have been experimentally combined in this occasion. Activities were coordinated by DPC and carried out in collaboration with the Architecture Department of the University of Ferrara, which provided an operative and scientific support in the whole development of the work.

An investigation methodology, based on a scientific approach for historical structures, has been applied to the case study of the Duomo di Milano. In particular, a continuous process of data acquisition, analysis of structural behaviour, diagnosis and safety evaluation is followed with the aim of assessing metallic ties present in the Cathedral. Different techniques and fields of expertise were used for data acquisition: historical investigation gave important information on the ties origin, their structural purpose and the construction process of the Cathedral; the wide experimental campaign included visual inspection, material characterization, and dynamic tests on the original ties and contributed to the understanding of the structural system. The main results and considerations from such a multidisciplinary investigation are presented in the paper, providing a reference from a real case-study. Relevant aspects for the study of the Cathedral’s structural behaviour are addressed, various approaches to be used are proposed, such as limit analysis or Finite Element Modelling (FEM) and their benefits are outlined. These models, once validated through the prediction of past and present states of the structure, will be used during diagnosis and safety evaluation to predict the future behaviour, or identify potential causes of eventual observed damage, as well as to evaluate the current state of the stress in ties measured with a more refined Non-destructive testing (NDT) approach.

The research line MOdihMA (MOisture detection in historical MAsonry) proposes to improve the innovative techniques recently developed to measure different parameters related to water content in masonry, that has an important role in the damage of historical buildings. The first objective of this project is to compare the effectiveness of the different methods in understanding how the quantitative data obtained are directly related to water content. The second objective of the MOdhiMa project is to compare the ability of the different techniques to map water as a function of its location and depth within the masonry structure, both on macro and micro-scale. A selection of these innovative techniques recently had an application on the “Sala delle Asse” in the Sforza Castle in Milan. The hall is famous for the decoration of the vault and the monochrome on the northwest wall, attributed to Leonardo. Recently Milano Municipality defined the plan of diagnostics for detecting the causes of the increasing damage on the painting and the poor conditions of conservation of the vault. Unilateral NMR, SUSI, IR Thermography, gravimetric and chemical tests were applied for mapping the moisture distribution in the bottom of the northwest wall. The comparison with the results of the standardized techniques confirmed the low moisture content distributed in the masonry.

From the date of its construction the chapel of the Blessed Virgin of Miracles is an important reference for the devotional Milanese population. It is so significant that the funding for its construction are raised thanks to the offerings of the faithful people visiting the church of S. Maria alla Porta, attached to which the chapel was built in 1705 to preserve the image of a Madonna and Child found—by chance—in the same church during some maintenance works carried out in 1651. During the XVIII and XIX centuries the chapel and the painting acquire an increasing importance and affection that will continue to grow until the tragic events of the World War II and, in particular, the bombings of 1943, which destroyed the chapel, saving only the wall adjacent to the church even if severely disfigured. The project of conservation and reuse aims to give back the building and its values to the city, valorizing the two crucial aspects that have characterized, and still characterize, the chapel. The one linked to the devotion to the Virgin and the other connected to the memory of the wounds caused by the war. Despite the small size of the ruins, the approach to the conservation project has been set on a strong multidisciplinary approach which allowed to reach excellent results in terms of knowledge of the status quo of the remains from both morphological/material and historical/documentary points of view.

During the last 10 years an inter-disciplinary campaign of surveys, researches and analysis has been undertaken on the buildings of the historical Archive and the church of the B.V. Annunciata in the

Ospedale Maggiore

in Milan, dubbed from the milanese the

Ca’ Granda

. The campaign was urgently appointed in 2002 by the Cultural Heritage Service of the Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, as a consequence of the worrisome structural conditions, the clear suffering signals displayed by the places and the severe environmental conditions. Moreover it had to be taken into consideration the vulnerability of the valuable multimaterial cultural heritage (manuscripts, paintings, wood libraries, sculptures etc.) that has been hosted here for centuries. We could count on a rare disposal of financial resources and time that made it possible to improve and to refine through the years the steps, the methods, the tools, and the goals themselves, given the priority to the going on of the original and historical function inside the places. It should be stressed that despite the well known importance of the places, as far as the history of architecture and of restoration are concerned, the progress of the researches and the multidisciplinary approach led to a true rediscovery of the identity, the role, the specific history, the material features and the artistic arrangement of some hidden and forgotten places of the Ca’ Granda, such as the crypt and the sepulchres below the church of S. Maria Annunciata. We were given the opportunity to set up and coordinate a well cooperative team that has followed the different steps of the work, including the researches on the archive sources, the geometrical survey, the stratigraphic survey, the detailed description of the building features and conditions, done room by room, and a broad campaign of diagnostic tests and analysis on the structures, on the materials and on the microclimate. A thorough knowledge was gradually increased during the years, thanks to the disposal of new resources, with the primary aim to permit a well planned program of interventions for the maintenance and for the conservation of these once forgotten places, giving the priority to the strengthening of structures.

First results on the knowledge of the stratified complex of Grancia of Cuna derived from interdisciplinary researches and from works of preservation in progress. Methods of analysis and interrelation of the contributions derived from various professionals involved in the project of conservation and re-functionality.

Can a seismic event be seen as an opportunity for the conservation of architectural heritage? This question was the starting point for the discussions that were held during the feedback from the cognitive analysis which was in turn preliminary to the formation of the Reconstruction Plan of Fossa, one of the many small historic settlements heavily damaged by the L’Aquila earthquake in 2009. In this study, the medieval castle which characterizes the historic centre, becomes the paradigm to show that, if the post-earthquake reconstruction is tackled with a perspective that focuses on sustainability and preservation of the building fabric, the monuments, which are at its heart, will inevitably be involved in a new phase, that recognizes in their historical nature the profound meaning of their beauty.

Starting from the damage condition of the small Saint Agata church affected by 2009 L’Aquila earthquake, a procedure of carrying out the restoration project is presented. It pursues dual design goals that bring together seismic safety and conservation of the monument establishing a rigorous correlation between the different phases of the design process. The methodology assigns particular importance to the cognitive analysis, both on the monument and historical sources, and to the interpretations of the investigation results as they allow the identification of the vulnerabilities which characterized the building at the moment of the earthquake. Specific observations on the evolution of the church and the current deterioration (both structural and superficial) reveal the crucial features, which help to explain the damage suffered and become an essential part in the definition of a consistent restoration program. The close link established between the cognitive analyses and interpretation becomes essential for the outlining of the criteria and the correct strategies for the project definition.

The nineteenth-century technological revolution gave birth to a brand-new kind of monumental architecture—the secular “cathedrals” of the bourgeois called commercial galleries. They reached their ultimate incarnation as such in the Italian case of “Vittorio Emanuele II” counterpointing the sacred Milanese cathedral over a common square. Cathedrals were those “books of stone” that once embodied building codes of monumental architecture. Innovation became necessary with newly-developed typologies and materials. It was exactly the iron-glass covering that revolutionary element of the “gallery” typology which bridged architecture and advanced technologies. The Milanese one was a “book of bricks, metal and glass” encoding spatially genuine Italian concepts and practical knowledge on bonding traditional materials with modern ones. Demanding immediate attention is their adequate profiling and translating into practical guidelines. Even though “Vittorio Emanuele II” was thoroughly researched, its iron-glass structure offers field for further investigation on innovation. The initial aim is two-fold: first, to unveil the complex of creative ideas enclosed in the crystal skies of the Milanese gallery and the technical decisions behind them; second, to trace those which survived the numerous restorations and the adoption of advanced techniques in resolving the variety of problems verified over the years. As far as creative ideas and technical solutions are concerned, there are three main examples which could be highlighted. The first one regards the 15-m span of the coverage designed deliberately without visible reinforcing rods. The second intriguing aspect was a perspective effect in the glass cladding achieved by the glass plates’ overlapping. The third technical solution of interest concerns the glazing bars and their expediency in the effective resolving of the famous water-leakage problem. The fate of all the original design ideas and technical solutions changed on a number of occasions of ordinary and special maintenance and occasional replacements. In the rich history of interventions in the roof, its partial reconstruction after the Second World War occupies a central place. In it, the cross-like section of the glazing bars along with the spatial configuration of the glass plates were consciously observed criteria for their substitution in order to assure the fruition of the perspective effect by future generations. Another case of preservation in the post-war intervention was the profile of the new main metal arches replacing the severely destroyed original ones. Each new arch was composed by segments instead of being produced as a whole piece. Moreover, the diversity of problems began right after the completion of the cover in 1868 and continues to the present day. Multiple disciplines are involved in the search of their solution: from history of architecture for an efficient archival investigation to material chemistry and physics for preventing damages in the contact zones of bricks, iron or pig-iron and glass, caused by their different thermal expansion coefficients; from brittleness of the nineteenth-century metal structures, accompanied by severe corrosion in the metal joints, to the structural-engineering issue of instability of the lantern bodies. The very challenge before the required multidisciplinary approach is to invent advanced solutions respecting the genuine concept behind the original ones. The ultimate objective is not only to trace nineteenth-century ideas and their technical solutions but also to introduce them as future-intervention guidelines for the purposes of sustainable preservation.

Architectural preservation in Japan is discussed through the study and observation of Gekko-den pavilion at Gokoku-ji Temple in Central Tokyo. Gekko-den’s importance lies in its affiliation with Onjo-ji Temple, founded in early Heian Period, 672, a designated National Treasure of Japan and head temple of the Tendaijimon Buddhist sect. Preservation of Gekko-den began in November 2008 and continued through to October 2013. Through the process of preservation at Gekko-den pavilion, current issues are brought to the fore, namely access to preservation materials necessary for repair and maintenance, access to a skilled knowledge base of craftsmen who hold the understanding and expertise pertaining not only to the material, but also the intricate and complex designs surrounding large Japanese wooden heritage structures. A fundamental understanding of how the material works within the intricate structure is two sides of the coin. Often intangible skills are held up as being necessary to the survival of preservation. This is unequivocally true in wooden preservation where the importance lies in a deep understanding of the wooden material and the way it works and an understanding of the structure. Analysis of the administration that functions to oversee the protection and preservation of cultural properties is examined, together with training and access to available necessary materials for the preservation.

This project examines South Korean preservation practices applied to

hanok

: vernacular wooden structures built during the Joseon (Chosŏn) Dynasty (1392–1910) through the first half of the twentieth Century. The analysis will evaluate preservation policies, practices and methodologies as products of relationships between heritage management institutions, communities inhabiting architectural heritage sites, vested interests’ land development projects, varying levels of awareness of heritage building values, and the understudied features of

hanok

architecture. The project illustrates the analytical and evaluative issues with case studies that reveal architectural design driven by sophisticated, yet under-stated aesthetics, interwoven with multi-disciplinary intellectual and multi-faceted scientific factors to an extent unique in East Asian architecture. The preservation zones selected to further illustrate this project offer unique case studies of architecture intrinsically tied to people in ways that are distinct in the cache of world heritage sites. This research expands on institutional definitions regarding proper preservation methods or policy by reintroducing traditional techniques that have evolved over centuries for maintaining the structure: technologies largely neglected in current preservation policies and procedures.

In addition to the well established standard photogrammetric techniques, another type of photogrammetry has been proposed by the Author, the so-called PSP (Panoramic Spherical Photogrammetry). This photogrammetric technique is particularly suitable for architectural surveys. Multi-image spherical panoramas are used which are partly overlapping digital images taken from the same point in order to obtain an all-round 360° cartographic representation of the sphere. There are many advantages: the speed of execution, the drastic reduction of traditional photogrammetric models, the completeness of the documentation, the FOV can be 360° wide, the absence of distortion, and most importantly the low-cost, thereby allowing a photogrammetric survey to be carried out which is, fast, complete, accurate and inexpensive. After a description of the principles of the PSP technique, a few examples are shown. Up to now some 500 projects have been run, ranging from the very initial phase of taking photographs, to the final rendered model. The procedure is very quick in the first phase while, on the contrary, it is time consuming in the orientation phase and above all in restitution, as it is still fully manual. Although only a few projects have been finished, this is precisely the rationale behind the technique: to build up an archive of oriented images (panoramas) which can be retrieved, observed, and used when required.

The survey work of the Piacenza Cathedral was an extended, articulated and involving operation. Being the survey of such a complex building it took time and attention to produce a correct and complete documentation and a full and judicious coverage of all the exterior and interior parts of the whole church. The whole survey was a digitally born work, based on the use of both time of flight and phase shift technologies to allow a good, reliable, and easy to manage dataset. All the models were completely textured from the data gathered in an extended and specific photographic campaign. Even if a meaningful part of the data post processing was aimed to the creation of classic 2D drawings, the digital survey was also the base for the developing of multimedia presentations, while the 3D digital model was developed according to a logic aimed to produce a good and versatile base, capable to be reused for further BIM usage while for certain specific parts there was the testing of innovative visualization solution, like direct point cloud visualization inside a rendering software based on the voxelization of the points. In general the work on this large building was guided to produce a “state of the art” work, careful about the architectural language, useful for documentation, monitoring and visualization and in its own way a “summa” of all the good procedure such a Built Heritage monument was worth to deserve for a contemporary and well working documentation.

Two years ago, the earthquake that devastated a wide architectural heritage in the Emilia area, in Northern Italy, gave rise to a series of surveys and investigations aimed at both documenting a lost or seriously compromised heritage and at recording information that can be used by different operators (i.e. fire departments, civil protection, engineers, architects, urban planners) and for different uses in different times, concerning the development of safety, recovery, restoration or demolition programs. The aim of this contribution is to show how digital technologies and in particular non-contact 3D survey methodologies can be used as an indispensable practice in order to rapidly and safely produce graphic documentation about an architectural heritage that has been destroyed or severely damaged by a natural disaster. The presented case studies belong to a repertoire that ranges from single buildings to wider complexes that were selected for their historical and cultural importance and for the urgency of the development of intervention plans.

The goal of the 3D-ICONS European Project is to provide EUROPEANA (

www.europeana.eu

) with accurate 3D models of architectural and archaeological monuments and buildings of remarkable cultural importance. The purpose of this paper is to describe the specific processing pipeline that has been set for digitizing a significant part of the Civic Archaeological Museum in Milan (Italy). All the technical and logistic aspects needed for capturing 3D models in a Museum environment, the implication with IPR, and the metadata acquisition, are covered. The main issue is generating a good result by the technical point of view, minimizing the impact on the usual Museum activity during the 3D capturing operations, shortening in the meantime the processing time to the minimal allowed by the different applicable techniques. This condition has led different choices related to the survey technologies (laser scanning and image based modeling) and the related data processing. Both technical and descriptive metadata have been collected for each item acquired, for generating a record of data searchable on EUROPEANA, with the addition of new metadata not defined in the minimal record, for making traceable the path leading to the generated digital content. The paper gives a general discussion of such issues with some specific examples referred to the large set of 3D objects digitized within the 3D-ICONS project.

The restoration and preservation of built cultural heritage requires a good knowledge of its history and its current state of conservation. Heritage con-servation professionals are used to perform mappings to record and disseminate data relative to the monument. Data to be collected are heterogeneous, starting from the oldest sources (such as archives or iconographic manuscript) up to field observations. This study is applied to the documentation and analysis of the state of conservation of the East tower in the castle of Chambord. The produced map-pings concern the dating of stonework, the nature and origin of each stone, and the distribution of degradation patterns on the outer walls. To enable the graphical drawing and viewing of the different mappings, it is necessary to produce a suitable digital medium. In this study, the medium is a textured 3D model as a mean to characterize accurately and actually all surfaces, including those that cannot be viewed on a 2D projection. This 3D model is associated to the NUBES database to store and analyse all collected data. NUBES is a web-based open source platform for the representation, documentation and analysis of architectural elements. This information system has been specifically developed to include an interface dedicated to the drawing vector mappings and to their organization into hierarchical layers. Results of this study can be used to improve the monument diagnosis and our knowledge of weathering processes.

This paper describes the design and development of Onna—Past, Present and Future, a multimedia installation for the museum of Onna (L’Aquila, Italy), a space dedicated to the memory of the town affected by the earthquake in April 2009. Our work consists of a natural interaction system, a user profiling system and a mobile application integrated together in order to provide visitors of the museum a multi-modal experience of the events related to the disaster. Tourists and citizens of Onna are for first invited to visit the interactive installation in which multimedia assets about history, architecture and life of the town are presented. User activity is recorded by a profiling system in order to extract a profile of interest for each visitor. In a second stage of the experience users leave the museum and visit the town. They can start the application on their smartphone, which connects to the indoor profiling system via an Internet connection and then shows suggested personalized and geo-located in-depth information based on the actions performed during the session with the interactive exhibit in the museum.

Digital Storytelling is emerging as “the” way to engage cultural heritage institutions’ visitors, both virtual and real. The wide spreading of media and devices have made stories the most expected way to talk about culture: a “traditional” webpage is distractedly read on the screen or (in the best of cases) printed for later reading; a multimedia story, instead, can be listened to in various situations: in front of a PC at home but also in the street, on a train, sitting at a café, while visiting cultural venues, etc. This paper introduces a specific approach to digital storytelling that is modular (in the sense that the various content elements can be combined in different ways), multi-channel (in the sense that the “stories” can be delivered online and off-line, over all modern channels and devices) and multi-scenario (in the sense that various user scenarios can be covered). All of this at a reasonable cost/effort. This approach is supported by a tool, developed by HOC-LAB of Politecnico di Milano in cooperation with TEC-Lab, Università della Svizzera italiana, named “1001 stories”. 1001 stories has been used to produce more than 30 professional stories, mainly in the field of cultural heritage.

In this study, the use of hydroxyapatite (HAP), recently proposed for limestone consolidation, was investigated on unweathered and artificially weathered Carrara marble and the behaviour of HAP-treated samples towards thermal weathering was evaluated, by means of an accelerated thermal weathering test. The results of the study indicate that HAP is a very promising consolidant for marble, able to significantly improve mechanical properties without substantially altering pore size distribution and to provide some mitigation against thermal weathering.

A novel biomimetic nanocomposite was synthesized by the sol gel process in order to reduce the main drawbacks of tetraethoxysilane (TEOS)-based consolidants, such as crack formation upon the drying process and insufficient bonding to carbonaceous substrates. The reaction route involves the addition of a colloidal solution of synthesized nano-calcium oxalate to TEOS producing a crack-free mesoporous xerogel with pore radius of approximately 15 nm, with application to stone conservation. Calcium oxalate which is the main component found on the patinas, was synthesized by the reaction of calcium hydroxide with oxalic acid in the presence of isopropanol. Finally, n-octylamine was added to the mixture, as surfactant. The effectiveness of the new consolidant was evaluated on bioclastic limestones, which are frequently found in historic and modern architectural structures in the Mediterranean basin. The hygric properties and tensile strength of treated samples were improved without affecting either microstructural characteristics or causing phenomena of overstrengthening.

Ammonium oxalate treatment of calcareous stone has, in recent years, emerged as a conservation treatment with both consolidating and protective properties through the surface conversion from calcium carbonate to calcium oxalate. This treatment on Maltese Globigerina Limestone has also produced positive results, increasing the acid resistance while retaining the water transport properties of the stone. Furthermore, treatment in the presence of sodium chloride did not impede the conversion. This paper focuses on ammonium oxalate treatment application in the presence of sodium chloride as well as sodium sulphate and sodium nitrate, in a comparative study where the treatment was applied to quarry samples of this soft Limestone under laboratory conditions. The resistance to salt crystallisation and the water absorption properties were subsequently studied. This stage in the understanding of ammonium oxalate treatment of calcareous stone under different soluble salt content conditions is an important step towards carrying this treatment forwards to real site conditions where soluble salts are naturally present in the stone and where desalination may prove to be difficult or impossible. Results obtained were positive in all respects and show that ammonium oxalate treatment may be relevant in the treatment of this stone type.

In the frame of the EU-project NANOMATCH new consolidants based on metal alkoxides were developed and tested. New compounds were prepared with different synthetic pathways to overcome the oligomerization issue, which can strongly influence solubility and therefore application of alkoxides as conservation materials for built heritage. Calcium alkoxides react in presence of humidity and carbon dioxide to give CaCO

3

and alcohols. This peculiar behavior -in atmospheric conditions- makes this class of chemicals suitable for consolidation of carbonate stones, plasters and wall paintings and also for pH buffer to avoid acidification of cellulose based materials such as wood and paper. Within the frame of the project, it has been demonstrated that the developed calcium compounds are more soluble than the corresponding commercial Ca-bearing consolidants and, after reaction with air, they evolve into different calcium carbonate structures, i.e. amorphous carbonate or crystalline calcite and vaterite. The ratio among these forms can be oriented by environmental conditions and treatment with water, in order to force a carbonate phase in place of other ones. Commercially available magnesium alkoxides solutions were also tested as consolidants precursors. Carbonation of magnesium compounds brought to precipitation of low crystalline Mg hydroxide and carbonate coatings. Moreover, hydrated Mg carbonate phases were identified. Many of them are salts sensitive to water and prone to ion-exchange, possibly evolving to soluble magnesium salts deleterious for stone. These experimental evidences led to the decision to discard magnesium alkoxides for conservation purposes.

In this study a silane polymer and an inorganic nanoparticles (TiO

2

)/polymer composite coating have been tested as protective agents on three different substrates, Carrara/Botticino marbles and Angera stone to improve their hydrophobicity features. The coatings obtained turned out to be hydrophobic as concerns the sylane polymer and superhydrophobic in the case of the hybrid coating. Aging tests have demonstrated the stability of the surface colours.

An extensive restoration project was realized in the Archaeological site of Pella, in order to consolidate ancient stone remnants by filling them with mortar and manufacture artificial units of stone for anastylosis purposes. Samples of ancient stones were analyzed, regarding their morphological, physico-mechanical and chemical properties. Based on the evaluation of the analysis results, repair mortars were designed and tested for their compatibility with old stones. An in situ monitoring of the repair works took place, while samples for testing were taken from the site 2 and 5 years after the interventions. In this paper the results of the analysis of an adequate number of repaired and artificial stones are presented. The survey showed some cracks on few large stone units (100

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50

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30 cm) precast or cast in place. The analysis followed comprised color determination, measurement of compressive strength, modulus of elasticity and porosity properties. Microstructure examination was made, assisted by stereoscope and SEM-EDS, while soluble salt content and residual resistance to wetting-drying cycles were also carried out. The results were compared with the previous ones at earlier age, as well as with those of the authentic stone of Pella. Based on them, it seems that properly designed mortars are effective for consolidating or for completing missing parts of old stones without problems related with the existing microstructure and the resisting environmental cycling of the area. The characteristics of the designed repair mortars seem to be compatible with those of the old stones. The cracks appeared in some artificial stone units could be attributed to thermal load effects, as well as to lack of adequate curing.