Tarihi ahşap yapı taşıyıcı sistemlerinin incelenmesi ve Boğaziçi örneği: Amcazade Hüseyin Paşa Yalısı
The analysis of historical timber buildings load bearing systems and a given example Amcazade Huseyin Paşa Mansion in Bosphorus
Yazar: SELÇUK UZUN
Danışman: PROF. DR. FATMA GÜLTEN GÜLAY
İstanbul Teknik Üniversitesi / Fen Bilimleri Enstitüsü / Yapı Mühendisliği Ana Bilim Dalı
Derece: Yüksek Lisans, 2018
Konu: İnşaat Mühendisliği = Civil Engineering

Özet:
Kültürel miras olarak geçmişten günümüze kalan ve tarihe ışık tutan eski eser yapıların, korunarak bir sonraki nesillere aktarılması toplum olarak görev ve sorumluluğumuzdur. Eski eser ahşap yapıların korunması ve korunmasındaki süreklilik, yapının mimari özellikleri ile beraber en önemli hususlardan bir tanesi de yapıyı taşıyan ve ayakta durmasını sürekli kılan yapının taşıyıcı sistemidir. Bir önceki cümleye istinaden bu tez oluşturulmuştur. Geleneksel ahşap yapıları anlamak ve koruma, onarım, restorasyon, rekonstrüksiyon seçeneklerinin değerlendirilebilmesi, yapı taşıyıcı sisteminin yeterli olup olmadığını bilmekle mümkündür. Bu kapsamda ülkemizde ve İstanbulda özellikle Boğaziçinde her yıl yüzlerce ahşap köşk ve ahşap yalılar restorasyon uygulamasına tabi tutulmakta iken, restorasyon uygulamasının değerlendirilmesi veya uygulanacak teknik ve yöntemler, Kültür ve Turizm Bakanlığına bağlı ilgili Kültür Varlıklarını Koruma Bölge Müdürlüklerince belirlenmektedir. Mimari olarak belirli kıstas ve kuralların olduğu ancak statik olarak yapının taşıyıcı sistemi ile ilgili kural ve kıstasların fazla mevcut olmadığı bu değerlendirmelerde, yapının mevcut taşıyıcı sistemi teknik olarak tetkik edilmeden karar verilmektedir. Böylece, yapıda yapılacak müdahalelerde hangi durumlarının göz önünde bulundurulacağı, yapıya müdahalenin hangi kıstaslara göre verileceği, yapının taşıyıcı sisteminin yeterli olup olmadığı tetkik etmek ile mümkündür.
Beton, çelik gibi sanayi ürünü olan yapı malzemeleri gelişmeden önce, ormanların yoğun olduğu bölgelerde evler genellikle ağaçlardan elde edilen ahşaptan üretilmiştir. Yapı malzemelerinin ve inşaat tekniklerinin gelişmesi ile ahşap konut yerini, beton ve çelik malzemeye bırakmıştır. Geçmişten günümüze kadar kalan ve sayıca gittikçe azalan geleneksel ahşap yapılar, mimari olarak eşsiz görünüme sahip oldukları için bulunduğu bölgeleri süslemekle kalmayıp, tarihi bir hava katmaktadır. İstanbul'da, tarihi yarımadada ahşap köşkler, Boğaziçinde ahşap yalılar oldukça yoğundur. Geleneksel ahşap yapıların korunması ve korunma aşamasında yapılan uygulamalarda yapının taşıyıcı sistemi hakkındaki bilgi, korunma yöntemine ışık tutmaktadır. Bu kapsamda yapılan bu tezde ilk olarak tezin amacı detaylı olarak açıklanmış ve yapılan literatür çalışmaları hakkında bilgi verilmiştir.
İkinci bölümde, ahşap ve ahşap yapının tanımı yapılmış, ahşap yapıyı oluşturan taşıyıcı olan ve olmayan yapı elemanları açıklanarak şekiller yardımı ile gösterilmiştir.
Üçüncü bölümde, ahşap yapı malzemesinin fiziksel, kimyasal ve mekanik özellikleri irdelenmiş olup, ahşap bir yapıda oluşabilecek muhtemel fiziksel, kimyasal, biyolojik bozulmalar açıklanmıştır.Mevcut ahşap yapıların bozulma ve hasarlardan dolayı koruma ilkeleri göz önünde bulundurularak taşıyıcı sistemde yapılacak onarım ve vgüçlendirme metotları örneklerle ortaya konulmuştur.
Dördüncü bölümde, tarihi ahşap yapıların korunması ile ilgili evrensel olarak geçerli olan Venedik Tüzüğü, ülkemizde geçerli olan Kültür Ve Tabiat Varlıklarını Koruma Kanunu ile Boğaziçi Kanunu'nın amaç ve kapsamı açıklanmıştır. Yeniden yapılacak ahşap yapılara ilişkin uluslararası geçerliliği olan Euro Code 5 standardı, ülkemizde ise TS 647 Ahşap Yapıların Hesap Ve Yapım Kuralları ile Deprem Yönetmenliğinin ahşap yapılar bölümüne ait amaç ve kapsamı açıklanmıştır.
Beşinci bölümde, ülkemizde genelinde ve İstanbul Boğaziçinde bulunun tarihi ahşap yapılardan birkaç örnek verilermiştir.
Altıncı bölümde, örnek yapı olarak ele alınan Amcazade Hüseyin Paşa Yalısının tarihçesi, şimdiye kadar geçirdiği onarımlar ve divanhane kısmının mevcut hali ve yapıyı oluşturan tüm ahşap elemanların durumları incelenerek şekiller ile gösterilmiştir. Amcazade Hüseyin Paşa Yalısı divanhane kısmının taşıyıcı sistem rölövesi hazırlanmış ve yapı elemanlarının mevcut durumlarını göz önünde bulundurularak düşey yükler ve deprem yükü ayrı ayrı gözönünde bulundurularak yapı analizi ve kesit tahkikleri yapılmıştır. Yapılan analiz sonucunda; kesitlerin yetersiz olduğu yerlerde güçlendirme önerileri sunulmuştur.
Sonuç bölümde ise tez boyunca araştırılan konular kısaca özetlenmiş olup, tarihi ahşap yapılarda yapılacak müdahale yöntemlerinden bahsedilmiştir.

Abstract:
Historical buildings are the cultural heritage that remains from past to nowadays and each of them also a document enlightens the history of architecture. Preserving and restoring the old buildings is also important because those old monuments are the reflection of our history, they help us to understand and respect people who lived in different eras with different habits and traditions. As well the existence of old monuments will help us observe the changes in the societies for a better understanding of the reasons that lead to the development of cities and societies and even traditions to the current status. Old buildings are the face of cities they reflect the changes that happened in a city over time, they reflect conflicts, wars, and the prosperity of the society, it even reflects the economic condition of the city over time. Thus, it's a duty and responsibility to preserve these cultural heritages to hand down the next generations. Preservation cases and its continuity require interdisciplinary studies in terms of both architecture and engineering. It is a priority to make stable the historic buildings to conserve them. Loadbearing systems' condition of these buildings is the most significant element that is related to determine of the conservation techniques such as repair, restoration or reconstruction. For example, it's not possible to reconstruct a building that has a solid frame or repair simply a building that have damaged loadbearing system.
In Turkey, preservation rules are stated with laws and procedures by interdisciplinary studies. And these preservation cases are controlled by Cultural and Natural Heritage Preservation Board, Ministry of Culture and Tourism. However, these laws and procedures are mostly focusing on the architectural aspects without considering structural conditions. There are many buildings that restored in every year in İstanbul. But this restoration works are carried out without well-investigated structural analysis and calculations. As a matter of fact, it must be first to look on the structural system – loadbearing system-, and calculations of the structural analysis need to be done finickily.
During the last decades structural reliability methods have been further developed, refined and adapted and are now at a stage where they are being applied in practical engineering problems as a decision support tool in connection with design and assessment of structures. For materials such as concrete and steel, the application of modern structural reliability methods has led to an increasingly more consistent evaluation of the safety or reliability. Whereas some efforts in this direction have been undertaken also for timber, the developments, however, have been less impressive. One of the main reasons for this is that the variability of the timber material properties is much higher than for other building materials. Furthermore, the timber material properties depend on the entire load and moisture history of the structure. Prior to the development of manufactured construction metarials such as concrete and steel, buildings were often produced from trees, in regions where the forests were dense. By development of building materials and construction techniques, timber buildings gave place to concrete and steel buildings. So in Turkey, especially the regions where the density of forest is high, there are a lot of old timber buildings.
 In this thesis made with this concern firstly, the purpose is explained in detail, then academic studies about the subject are given briefly. The investigations for preparing this thesis showed that, large part of studies are about the architectural of historical buildings. There were not to much academic studies about the engineering. The researces was made about the old timber structures, old timber structures structural systems, reliability of timber structures, repair of wood structures, reinforcement of timber element, restoration of historical timber structures, inventory of repair and strengthening methods timber, significance of wood formation of traditional turkish architecture, the behavior of timber structures under earthquake loads and design of structural timber to Euro code 5.
Second part of the thesis mainly focuses on the timber structures. The definition of wood was made. The element of a timber structure such loadbearing system - foundaitons, walls, columns, beams, joints etc.-, roofs, architectural elements are explained with drawings in depth. The foundation system in a traditional turkish wooden buildings are generally starting from the top of ground. There are three types of foundations, stone foundation, column footing foundation and wooden pile foundations. Loadbearing system of a traditional turkish wooden structure mainly consist of column, beam and wall. There are different types of wall that changes according to fulling with wood, stone and it is empty. Joints are generally provided by using nailing and engagement of wood. Facade elements of a traditional turkish wooden building is also explained.
Wood as a material is examined in the third chapter. Physical, chemical and mechanical properties of the wooden materials described and analyzed within the both micro and macro scope. In micro scope, the microstructure of a wood consistent is examined. In macro scope, the physical shape and structure of a wood is examined. Furthermore it's investigated that deteriorations and damages which might occur in the timber structures. The reason that caauses deterioration of wood are generally as biologically plant, animals such as birds, insects, chemically nitric acid, salts, chlorate, physically, cracks, expansion of wood due to air conditions such as rain, shrink, surface wear of wood. In the last part of this chapter repairment and strengthining methods are demonstrated with the examples in consideration of conservation principles. Intervation metarials are steel, epoxy resins, wood, fibre reinforced polymers. Intervation techniques are removal, dismantling and replacement, addition of a new element, prosthesisation, sealing, repair of cracks, repair and strengthening of connections, post-tensioning. All of these methods are explained.
National and international conservation princples, laws and technical standarts which guide the interventions on the historic timber buildings compose of the fourth chapter of thesis. The Venice Charter (1964) which is the main state about preservation of the historic buildings in the world and also in Turkey, Conservation Law of the Cultural and Natural Heritage (1983) which is the main legal state in Turkey are explained. In additon to them Bosphorous Law (1983) which is a private law for the Bosphorous area in Istanbul is also explained. Euro Code 5, the international technical standart for the timber framed buildigs, is examined with the TSE647 Building Code For Timber Structures' Calculation and Building Rules and Earthquake Regulation.
In the fifth chapter, the example of historical wooden buildings in Turkey and in Bosphorus were given. Eşrefoğlu Mosque is the only wooden mosque where several decorative techniques of stone, brick, ceramics and painting were used together. It is still a mystery how the wooden portions of the mosque, built in 1299, lasted until today without decay Eşrefoğlu Mosque, built in 1299 in the Beyşehir district of the central Anatolian province of Konya, is an architectural mystery. Also in Istanbul, Buyukada, Greek Orphanage, the building is considered to be the largest wooden building in Europe and the second largest in the world. The orphanage consists of 206 rooms, a kitchen, a library, a primary school and vocational workshops. The building is still surviving. In Bosphorus, there are a lot of wooden mansions and the samples are given.
In the sixth chapter, Amcazade Hüseyin Paşa Mansion is examined as an example within the concerns that stated early part of this text. Firstly, a brief information about the building is given such as location and history of the building, importance of the building in the arhitectural history. The Amcazade Hüseyin Paşa Mansion was built at 1699 in Istanbul in Bosphorus. It is still surviving and it will be restorated soon. Divanhane of the mansion is analyzed in detail with help of the survey studies. These analysis are consist of the existing structure's condition, building material and joint elements. In order to have information about the all part of existing structure, the strucure element are surveyed one by one. Firstly the foundation of Divanhane was invesitagated. By having information about the foundation, the reasons that causes the deterioration of foundation were examined. Then, the load bearing system of Divanhane are investigated. Shape, number, dimensions of column was noted and the condition of column was investigated. All beam of the load bearing system also investigated and shape, number and dimension of them were noted. After having all information about the existing structure, It was researched whether the existing load bearing system is sufficient under certain loads. In this context, the effective structural loads are taken from the directive of "TS 498 Desing Loads For Buildings " and the existing structure system has been verified according to the directive of "TS647 Building Code For Timber Structures".
Strengthening and intervention suggestions are presented where the sections are inadequate. After making structural analysis, the results showed that, the load bearing capacity of beams where the length is maximum were insufficient. Columns are sufficient under loadings, columns have corrosions are exception. According to structural analysis, the intervation techniques and intervation metarials are determined. In stead of reconstruction of Divanhane, it is suggested that load bearing system of the building should be strengthed and intervation must be applied for some part of buildings where the system is insufficient.
In the conclusion chapter, the topics investigated during the thesis are briefly summarized and the intervention methods to be done in the historical wood structures are mentioned. All part of Divahane and the elements those constitute load bearing systems are handled one by one. For insufficent beams, it is adviced that, the direction and the system of plank must be changed, dimension of beam must be increased, for insufficients dimensions, new beam must be added to system. In order to decrease the deflection of beams, post-tesioning system must be applied. For colums which have corrosion must be replaced with a new one that has same dimensions and same metarials.