We will focus on 3 case studies of restoration and archaeology, as examples of how to preserve, keep and transfer cultural heritage to the future: the restoration of Forum Baths and Gymnasium, the restoration of the insula of Chaste Lovers, both in Pompeii and the restoration of the façades of the Coliseum in Rome. The Italian highly specialized company B5 S.r.l. was charged of the coordination and realization of these three projects.
FORUM BATHS AND GYMNASIUM IN POMPEII
This project is in the context of the Major Project Pompeii, great collective commitment and example of good practices and high executive skills. Pompeii - the largest archaeological site in the world - has been a UNESCO site since 1996 (it provides a complete and vivid picture of society and daily life during the Vesuvius eruption of 79 a.C., without parallel anywhere in the world). It possesses a rich and varied artistic heritage: mosaics, decorated surfaces, frescoes and stuccoes, decorative architectural elements. The project aims to arrest degradation, secure, removing the causes that threaten the preservation of items and that make some areas impossible to use of the so-called ‘Gymnasium’ (insula n. 5 on the north side of the Forum in the Regio n. VII). It forecasts some demolitions of concrete structures, as well, together with the project of new structures. The site has been object of scientific studies from all historical, archaeological, geological, material, architectural,botanical and structural points of views, with attention to the use for touristic visits and to planned maintenance for the future. The in-depth and wide-ranging investigations allowed to lead to a conscious design, based on the initial “recognition” of the values, and aiming at preservation and transmission of these values. The discovery of glass frames demonstrates the use of glass for windows in roman age, found almost intact, and described by architects and visitors in the past. Windows play a key aspect for Thermal baths, documenting an ingenious hygrothermal control system. The analysis of the internal microclimate tells that temperature and humidity conditions nowadays are not compatible with the preservation of existing stuccoes and frescoes. Big groups of tourists entering in a few minutes, make a big hygro-thermal load in the rooms, that drops dramatically at the end of the visit, until the incoming of the next group. This make the archaeological artifacts not able to achieve and maintain the conservative balance necessary to the preservation of materials.
The regulation of the group entrances with suitable devices has been evaluated within a flow planning, in order to control humidity and temperature, controlled by instruments, in order to monitor and create a history of the inner microclimatic conditions. In order to prevent the entry of rainwater and poultry, the project introduces then new solar control window frames with laminated magnetronic glasses. A complete survey has been done, keeping analytical accounts, stone by stone, and identifying all tracks and materials, as architectural and archaeological units, by distinguishing them in relation to the building history.
The project wants to maintain documentation of all phases of history. Analysis items are then associated with interventions in the drawings. Graphics and computer documentation base will also be used for locating the tasks performed on worksite.
This will allow, once restoration will be finished, to have a complete database with detailed graphic references, for monitoring and scheduling of maintenance activities.
The new structure for the roof confirms the same “shape”, putting new beams in the walls within the existing holes, only by changing the structure. Three different solutions were proposed: wood (no glue-lam but true chestnut timber), steel or Pultruded FRP Structural material.
The wooden solution was finally chosen by the Superintendence of Pompeii because considered as more similar to other cases already performed in Pompeii.
Some devices were adopted to improve the accessibility and the quality of the touristic visit, with new structures, in steel elements, multimedia space, where tourists can acquire information, in different foreign languages and explained in Braille on a tactile map.
INSULA OF CHASTE LOVERS
The second case study is linked to the restoration project of the insula of Chaste Lovers, located in the central district of Pompeii, the Regio IX (nine), with access from via dell’Abbondanza, one of the principal street in ancient Pompeii. The block extends over an area of approximately 4.000 square meters: a bakery and a shop connected to it, together with some houses (“Primo and Secondo Cenacolo Colonnato). Some rooms probably belong to a single real estate unit, the House of the Painters at Work. Another residential unit is the house of the Chast Lovers, with its frescoes and mosaics.
The insula has come to light for the first time in the early twentieth century. In 1943 it has been partially bombed and destroyed by Allied Forces, and it has been then restored through wide reconstructions. The last excavation and study activities date back to 1980: at this time the area was protected with provisional roofing systems, that nowadays still cover the entire surface of the insula, which is closed to public from many years.
Five different fields of actions were defined in the project:
_ consolidation of fronts of excavation;
_ archaeological excavations;
_ restoration and walls securing;
_ accessibility and valorization of the site.
All aspects of the project are closely connected to each other, not only in terms of restoration choices,but also of operational steps. The project is based on the principles of minimal intervention, reversibility, impact control, compatibility with the context and among materials, and “polite” possibility of distinguishing the intervention.
The existing provisional cover today is a patchwork of different sheets (top view) and, from the inside is a disordered dense forest of metallic pillars, having in many cases also the function to hold collapsing walls.
Structural investigations were made on the existing elements of the cover, revealing that they can’t assure safety conditions anymore.
The roof has to be replaced by a studied and designed new cover.
The new designed roof will be a definitive one, and it will help to keep the conservative balance of the archaeological structures and decorations.
It also meets the needs of preservation and improving of the accessibility at the insula.
The new roof has a reduced covered surface, conceived as a studied articulation of layers in relationship with the rhythms, the geometry and the spatiality of the ancient walls andthe rooms below, even considering the relationship between covered and open parts. The relation with the existing red clay roofing on neighbor domus is evocated through the polite suggestion of aluminum coating in a red color, similar to the color of tiles covered areas. The archeological open spaces, which correspond to the atrium or the courtyards, are covered by glass panels, that suggest the idea of “open sky” while providing protection to the underlying elements. The coverage is based on a metallic reticular spatial structure, with tubular rods and spherical nodes. The supports and foundations were designed and calculated in order to minimize the number and the dimension of the columns, reduced to the overall number of 12 (6 per side), placing them outside the insula, along the sidewalks of the western and eastern streets. The punctual foundations were positioned in already existing cavities.
Refined calculation permitted to limit their maximum dimensions. The positioning of seismic isolator on the head of pillars has contributed to a significant reduction of the size of the supports and foundations. Some further archaeological excavations were forecasted in order to secure the areas and the structures. Excavations will also achieve scientific goals, as research activities aimed at knowledge, study and documentation of archaeological layers and structures. The insula is in a rather good state of conservation, even if abandoned for years. This demonstrates the conservative efficiency and conservation benefits of the cover,which has protected walls and decorations from water action, direct solar irradiation, and extreme heating and cooling phenomena.
The archaeological walls - since they have no longer horizontal elements – do not have structural function, they must only fulfil their own stability standards. In the verifications, walls have then been considered as elements to be protected only under static conditions, without considering the action of the earthquake on them.
An accurate diagnostic campaign on archaeological structures has allowed to find out the quality of the structures and the mechanisms of ongoing disasters and their causes.
Walls with critical “static” problems will be assured with new external support structures in stainless steel, according to:
_ low visual impact;
_ limited extension within the room;
_ high durability of elements.
Fruition and valorization
The project of the Chaste Lovers insula also focuses on the fruition and valorization of archeological cultural heritage. In Pompeii touristic paths follow a “domestic” approach, dropping the visitor into a daily life dimension. This type of visit might sometimes contrast with the conservative nature of archaeological artifacts, which remain a priority. In the Chaste Lovers insula some rooms might not be visited by tourists in order to prevent their destruction.
The project forecasts therefore a suspended pathway, in order to allow the visit of these spaces without interfering with them. This approach enables to develop the visit of the archaeological heritage into a “museographic” way, and allow visitors to understand more, implementing their awareness of historical-aesthetic values. The two ways are complementary.
The insula of Chaste Lovers can be approached using the original path, by entering from Via dell’Abbondanza which is integrated by the footbridge, suspended from the roof, proposing a different view from the top. Both paths are opened to people with disabilities.
The Coliseum is a project and a 3 years lasting worksite ad it can be the occasion to pointing out and quickly “open” to some conclusions.
The restoration project of the Northen and Southern façades of Coliseum, which means on the whole exterior stone and bricks walls of the Flavian Amphitheatre, aims to clean, consolidate, protect and present the world famous monument.
Restoration has been done in the most appropriate, both traditional and innovative way, by paying special attention - anything but usual - to the preservation, beneath the layers of dust, dirt and crusts, to all the colors that the travertine stone has taken over time, including amber patinas of oxalates. We were not just supposed to clean carefully the two façades by some water nebulization, which is anyway a very difficult and highly specialized operation.
The question of this intervention deals with the relationship between surfaces and architecture, because the project was first considered in its previous scope of action, on a twodimensional direction. The idea was to clean surfaces as working on frescoes or plasters, forgetting that the Coliseum is an archaeological building.
The intervention that we made was therefore able to make a significant shift from the ‘two-dimensional ‘ to a ‘ three-dimensional ‘ - both volumetric and spatial – intervention of restoration and protection. And even – I dare say – it was able to include a fourth dimension, linked to the social perception of the whole operation in term of accessibility, visibility and dissemination during the worksite and to the transmission to the future not only of the restored surfaces of the monument, but also of its implemented knowledge.
The Roman Amphitheatre itself was considered and analyzed as an architectural, as well as an archaeological, theme of interposition. Restoration of architectural monuments must consider vertical surfaces together with horizontal ones, including all the protruding, angled and curved planes and volumes into a unified vision. The archaeological monument has been therefore studied as a complex “building system”: elements such as frames, jetties and horizontal planes are not only “decoration” elements, but they play an important role in protection and preservation. The whole system, starting from its constructive geometry represents a composite reality transformed during the times, under human and natural actions.
Knowledge and recognition of values are the basis in order to lighten and localize the causes of the action of external agents, such as rainwater, smog, weeds, micro-organisms.
The intention of the project of restoration is to facilitate the reading and not to erase the traces of time, according to the dictates of the Charters of restoration. The project method clearly defines the direction of “conservative” and “revealing” proposals of intervention, claimed from 1964 by the Charter of Venice, on an ancient monument but as much archaeological and perhaps - to a greater extent - architectural. The project of restoration answers also to the needs of implementing the monument with iron gates, in order to open or close the arches of the first order, according to a more flexible use of the monument and to security demands and standards. The solution took in account all the specific needs and controls using already existing holes for the mechanical fixing of the gates.
The guiding principles of this project aiming to PRESERVING, KEEPING AND TRANSFERRING CULTURAL HERITAGE TO THE FUTURE are screened and calibrated, through all the restoration process:
_ “potential reversibility”;
_ “minimum intervention” or, at least a “non-invasive” one;
The principle of “minimum intervention” and the vision of maintenance lead to delicate operations and recovery of deteriorated stones and bricks, carefully studied case by case.
The project develops a dual synergistic action. It provides the most effective presentation of the monument and, over time, it gives a complete ‘maintenance’ or ‘conservation planning’.
This corresponds to the current state of theoretical and methodological reflection on restoration, which considers prevention and maintenance as the most effective way to transmit heritage to the future.
The Coliseum worksite is already finished in Rome, the first restoration worksite is starting in Pompei. Tangible results can be shared among international scientific communities. Among the actions to be taken:
_ HIGHER SPECIALISED ACTORS AND LARGE COORDINATION EFFORTS (interdisciplinary dialogue - private and public actions)
_ TAKE INTO ACCOUNT THE ORGANISM IN ITS COMPLEXITY (different scales and different point of views)
_ RECOGNITION OF VALUES - HISTORICAL, AESTEHICAL, SOCIAL (from the story of restoration to the traces of time)
_ PRESERVATION BY ARRESTING DEGRADATION / REMOVING CAUSES (cleaning, consolidation, reintegration, protection)
_ GIVE SAFETY AND SECURITY TO BOTH STRUCTURES AND VISITORS
_ IMPLEMENT AND IMPROVE ACCESSIBILITY
_ RECORD ALL FINDINGS AND ACTIONS (graphic and database) PLAN MAINTEINANCE (what, when, who)
In conclusion a restoration project, in an archeological context, maintain its effectiveness references and principles as critically and scientifically shared. We preserve and keep in order to transfer the cultural contents, the layers of history, the structure and the materials themselves of the ancient monument, in the serene consciousness of being able to just slow down the relentless degradation, but not to grant an impossible - but anyway always pursued - immortality.
[by Francesca Brancaccio, Ugo Brancaccio]