Structure and materials

Transcription

1 JAJCE TOWN OF SYMBIOSIS BETWEEN NATURE AND BUILT ENVIRONMENT Omar Kapetanović, Džidić Sanin International Burch University, Bosnia and Herzegovina ABSTRACT City of Jajce have emerged and developed from prehistoric times, developing unique connection with environment which had a great influence on built heritage. From that symbiosis of given and created conditions both cultural and historical very significant and diverse heritage has been preserved. Heritage includes various examples from residential, religious, fortification, memorial, transport and public buildings architecture. Jajce represents unique phenomena of medieval city which had kept a lot of his authenticity. In a long city and surroundings history there were two main factors that influenced it s development: terrain morphology and build ambient. Remains of previous cultures date back to Roman period and most characteristic one is altar of Jupiter, and oriental deity Mithras altar the mid XV century. From XV century the funerary chapel has been preserved. Chapel is product of a local workshop with elements of medieval Gothic. In Ottoman period city haven t been much transformed into Ottoman city in urbanism manner, as it is a case with other Bosnian cities. Regardless a lot of existing significant buildings have suffered change of use and form. Medieval church and tower have been transformed into mosque of Suleyman II, and fortress acquired new towers for city defense. Characteristic for city panorama are family houses with steep wooden roofs covered with wooden shingles. First floor have been made out of somewhat more loose material with shorter lifespan and been colored in white, while ground floor and semi-basements were mainly built out of stone. Neither Austrian-Hungarian empire managed to change significantly the medieval defined city matrix. Building build in this period have harmoniously been incorporated into already built environment. Historical continuity is easily readable even from ancient times till today. Cultural monuments from different historical periods represent valuable elements of urbanism and architecture formed in collaboration with natural environment and they build strong Genius Loci represented trough harmonized connection between given environment conditions and built material heritage. This unique phenomena has been recognized and listed as part of world heritage of all human race. In that manner Jajce as a city should be perceived and treated in further development. 473 Keywords: Jajce, cultural heritage, historical heritage, architecture urbanism, Ottoman period, Austro-Hungarian period, genius loci

2 CITY OF JAJCE Historical overview Structure and City of Jajce have emerged and developed from prehistoric times, developing unique connection with environment which had a great influence on built heritage. From that symbiosis of given and created conditions both cultural and historical very significant and diverse heritage has been preserved. Heritage includes various examples from residential, religious, fortification, memorial, transport and public buildings architecture. Jajce represents unique phenomena of medieval city which had kept a lot of his authenticity. Even though the first written documents about Jajce date back in the 1396., development of the city can be traced back to neolith, that findings of material culture and traces of settlement on Varosice (Vaorisca, area near the waterfall) can prove. Based on the ceramic findings it is assumed there was a settlement on the site of the medieval fortress. That could have been a settlement which had the role of guarding the Vrbas and the customs station. Archeological traces that are still preserved date back to Roman period and are consisted of architrave, Medusa s mask and relief of Silvanus (Roman deity), but the most characteristic one is altar of Jupiter. By the middle of the fourth century, in this region the oriental deity Mithras was worshiped, and from that period alter of Mithras is preserved with characteristics of Roman provincial art. Funerary chapel that dates back to fifteenth century still resists the time. It is made by local masonry workshop and has elements of medieval gothic, similar to burial chapels that have been built in Europe between IX and XVI century. As the river Pliva represented the border between Adriatic and Pannonian, in Jajce it is to be found the elements of early Christian architecture from surrounding roman provinces. Later on due to its geographical position Jajce gained significance. The city was located on Roman road Salon- Servitium that was connecting the Adriatic with Pannonia. There is not enough data about the cultural transition from Antic to Slavenian. It has been known that in period of abandoning pagan customs and adopting monotheistic religion the church has played crucial role throughout its dioceses. Before the Ottoman period fortresses were characteristic and the most specific one is the fortress Sokol, that has been built near the spring of the river Pliva. This fortress is important from the historical aspect since it has been the residence of Hrvoje Vukčić Hrvatinć, which was later on moved to Jajce. In the XV century the area that has been ruled by Hrvoje Vukčić Hrvatinić spread from Adriatic coast to the border with Hungary and the Jajce has been its capitol. Developing as a city-fortress with primarly defensive function, Jajce have grown accoridng to economical growth of the ruled area and in accordance to some local needs. As the evidence of the Jajce s involvement in the former world trends are the findings of the Byzantine 474

3 coins and money of Salzburg archbishops. For the first time name of the city Jajce was mentioned in travelogue of the travel writer Ami Bouea by whome Jajce was built by model of Castel del Uovo, Naples area, that has been the host to Hrvoje Vukčić Hrvatinić during his visit to Naples s king Ladislav. Taken into consideration the close relationship of these two rulers, and the fact the king of Naples has awarded Hrvoje with the title of Duke of Split, and the influence that Italy had on Bosnia in that period it is quite possible that the supposed origin of the name is correct. After the death of Hrvoje Vukčić Hrvatinić in Jajce has been merged to the areas that were ruled by Bosnian king Tvrtko Tvrtković the Second that has settled in this city. During the time of Tvrtko Tvrtković s the Second heirs Stjepan Tomaš and Stjepan Tomašević, Jajce has been the capitol that quickly progressed. During the Ottoman period Jajce didn t take on the Ottoman city characteristics in terms of town planning as it happened in other Bosnian and Herzegovinian cities. Nevertheless most of the important facilities has changed its function and shape. The medieval church of St. Mary and St. Luke s Tower were turned into a mosque of Sulejman the Second, and the fortress gained towers to improve city defence. Family houses with steep wooden roof covered with wooden shingle have become in the city panorama main characheristic. The first floor that was made of material of lower quality and shorter duration was painted in white while the ground floor and basement were mostly made out of stone. Even the Austrian-Hungarians weren t able to change clearly defined medieval urban city matrix. Objects that were built in this period have harmoniously fit with the inherited built structure. ST. MARIA CHURCH AND ST. LUKE S TOWER Historical overview 475 Historical periods that city of Jajce has been through have left architectural structures as representatives of these periods and there are some of them that have emerged in one period and evolved in following periods. The most important building that has these characteristics and that dates from the medieval period is the church of St. Maria with the St. Luke s tower. This building was primarily built as a simple one nave basilica in early Romanesque style. If the Bobovac was made under the influence of Hungarian cities, then Jajce has been made under the influence of Adriatic cities with a lot of visible elements of Romanesque style seen on St. Luke s tower. On the west wall there is a portal with decorative twisted rope with and profiled jamb that used to be the main entrance to the church of St. Maria. Above the portal is circular opening with profiled frame. On the south facade the existence of a porch with Romanesque styled columns was uncovered, but the size of the initial church that has been adapt in the

4 Gothic style in XV century has not been determined. This adaptation consisted of adding apse on the east side, and sacristy on the south side. In the church yard there was a cemetery, but till today only one gravestone ornamented with motives of half-moon and shield with swords still exists. Church frescoes originating from fifteenth century are preserved in zones that were buried under the rubble and are attributed to Dubrovnik craftsmen. The church had a rich art decorations. In the church ruins the remains of a hand of a sculpture with a candlestick is indicating a plastic decoration. Structure and Figure 1 Church of St. Maria and St. Luke s tower, Jajce, October Local craftsmen from this period went on trainings outside of Bosnia and they brought influences of stonemason schools from the west and the Mediterranean. The St. Luke s tower was added in the first half of the fifteenth century on the north-east side of the church of St. Maria. The tower has Romanesque elements with visible domestic influences. The influence of Adriatic architecture of Romanesque towers, in Split and on the island Rab, are rather visible. The tower 476

5 narrows towards the top, and it s triforates are typical for towers built in Adriatic cities. There are three rows of triforates, or division of the façade to floors, that is typical for this type of towers. Ultimately the tower is designed in the style of Dalmatian-Venetian Gothic. This is indicated by Gothic profiled cornices and cornices in the height of capitels. The activity of local masonry workshops was at it s peak between XIII and XV century and left behind significant architectural elements. The workshop of Andrija Alešija and influences of Hungarian stonemasons from XV to XVI century was particularly significant. When the church of St. Maria got transformed into a mosque, that happened in VXI century, the medieval plastic and polychrome decoration was destroyed. Floor of the mosque was raised after a fire in when the portal on the west side and rosace got closed. The south wall was rebuilt with a mihrab. Sofas, window openings and a new entrance to the building were added on the west wall. The tower went through changes too. All the openings got closed and the minaret top was added with Şeref. National Monuments preservation commission of Bosnia and Herzegovina declared in 2003 the whole architectural complex of Church of St. Maria (turned into Fethija or Sultan Sulejman mosque, in 1528.) with the St. Luke s tower a national monument and gave recommendations for the treatment. Figure 2 Floorplan, Church of St. Maria and St. Luke s tower, Jajce 477

6 Figure 3 East and west facade, Church of St. Maria and St. Luke s tower, Jajce Structural Overview of the St. Luka s Tower Substructure and part of the superstructure above ground level of the tower have been made of tuff and sandstone blocks. The masonry mortar used for masonry works have been deteriorated so much, that remaining material is much closer to the sand than mortar, so the walls were actually dry rubble masonry walls. Upper part of the superstructure above masonry walls have been made of corner sandstone block s columns with stone arches above them. The mid columns between corner columns have been made as twin columns made of monoliths. Such structure has been repeated through three floors. Figure 4 Cracks in the walls of the tower 478

7 Some mid columns inclined from vertical axes due to horizontal forces, probably caused by earthquakes. There are also visible almost vertical cracks in the walls of the superstructure, except the side wall that is integral part of the basilica wall. During the investigation geotechnical survey of the load bearing soil below the tower, it was found out that walls have no footings and that walls were supported on tuff, but there was cavity below part of the substructure. This is was one additional reason for minor inclination of the tower. 479 Figure 5 Structure of the St. Luka s Tower

8 Based upon these findings, it was necessary to rehabilitate the structure of the tower. The structural designer was Prof. Dr. Ismet V. Tahirović. The first part of the structural rehabilitation was rehabilitation of the foundations, where existing stone masonry foundation walls were encompassed by new RC walls, thus creating the footings that transfer load to stepwise shaped load bearing tuff. Design prescribed the rehabilitation of the foundation of the basilica wall that is monolithically connected to the tower wall as well, by interpolation of four pad foundations below the wall, but this work has never been done. In specific points of the tower, injectable emulsion was used to connect stone blocks in the wall. Additional RC ring beams were installed within the stone walls and covered by the same stone from the interior to be invisible, to take over seismic forces in bottom part of the superstructure. Special steel structure was introduced in upper part of the superstructure inside the tower to takeover seismic forces for upper superstructure. Structure and These works were done in 1984 and 1986 and St. Luka Tower still withstands the time and proudly represents the History of Bosnia and Herzegovina. Figure 6 Structural Reinforcing Elements of the St. Luka s Tower - drawigns 480

9 Figure 7 Structural Reinforcing Elements of the St. Luka s Tower photo 481 Figure 8 The assumed appearance of Fethije or Sultan Sulejman mosque from 1528

10 CONSLUSION Historical continuity on the example of Jajce is clearly visible from Antics till today. Cultural monuments from different historical periods represent valuable elements of urbanism and architecture created in relation with the natural environment and form a strong Genius Loci which is represented in harmonized relationship of natural features and built heritage. This unique phenomenon is an important component of the World Heritage and is a universal good of all people. Therefore clearly defined guidelines for further development of Jajce should be designed. Structure and BIBLIOGRAPHY [1]Andelic, Pavao Jedna etapa izgradnje srednjevijekovnog Jajca, Zbornik Krajiških muzeja II, 1963/64. [2]Basler, Duro Manji nalazi iz starije prošlosti Jajca, Zbornik Krajiških muzeja II, 1963/64. [3]Bojanovski, Ivo Sokol na Plivi, Naše starine XVIII, Sarajevo, [4]Hadzimuhamedovic, Amra, Komparativna analiza Historijskog područija Jajca, Nominacijski fajl, Komisija za očuvanje nacionalnih spomenika Bosne i Hercegovine, Sarajevo, [5]Lovrenovic, Dubravko Hrvoje Vukčić-Hrvatinić i splitska komuna, Prilozi Instituta za istoriju u Sarajevu, Sarajevo, [6]Sevo, Ljiljana - Jajce u narodnoj tradiciji, putopisima i umjetnosti, Nominacijski fajl, Komisija za očuvanje nacionalnih spomenika Bosne i Hercegovine, Sarajevo, [7]Truhelka, Ciro Kraljevski grad Jajce, Povijest i znamenitosti, Sarajevo, [8]Tahirović V.I. - Sanacija i ojačanje konstrukcije tornja Svetog Luke u Jajcu, Prvi kongres DGK BiH, Zbornik radova, Knjiga 2, Sarajevo 1989.god. 482