Kamu binalarının restorasyon süreçlerinde süre ve maliyet aşımını etkileyen faktörler: Analiz modeli
Factors affecting time and cost overruns in restoration processes of public buildings: Analysis model
Yazar: SERRA ERSOY ŞAHİN
Danışman: PROF. DR. HÜSNÜ MURAT GÜNAYDIN ; DOÇ. DR. GÖZDE BAŞAK ÖZTÜRK ÖZERAY
İstanbul Teknik Üniversitesi / Lisansüstü Eğitim Enstitüsü / Mimarlık Ana Bilim Dalı / Yapı Bilimleri Bilim Dalı
Derece: Doktora, 2024
Konu: Mimarlık = Architecture

Özet:
Türkiye'de kamu kullanımında olan yüzlerce tarihi nitelikte yapı bulunmakta ve her yıl bu yapıların restorasyonu için önemli kaynak ayrılmaktadır. Restorasyon projelerinin yönetimi, disiplinler arası ve kurumlar arası iş birliği, detaycılık, uzun vakit ve finansal kaynak gerektirirken, proje hazırlık aşamaları, onaylanma ve uygulama süreci de çalışmaların verimliliğine doğrudan etki etmektedir. Tezin amacı kamu binalarının restorasyon süreçlerinde süre ve maliyet aşımını etkileyen faktörlerin ortaya çıkarılması, birbirleri üzerindeki etkilerinin analiz edilmesi ve ortaya çıkan sonuçların ileride süre ve maliyet aşımını azaltmak için yorumlanmasıdır. Tez çalışması kapsamında; literatür araştırması, yarı yapılandırılmış görüşmeler, anket çalışması ve elde edilen bilgilerin analizleri yer almaktadır.
Araştırmanın temelini; kamu binalarının restorasyon projesi sürecinin herhangi bir aşamasında yer alan Vakıflar Genel Müdürlüğü çalışanları, müteahhitler, mimarlar, inşaat mühendisleri, saha çalışanları, danışmanlar, akademisyenler ve bunun gibi katılımcılar oluşturmuştur.
Kamu restorasyon projelerinde (KRP) karşılaşılan süre ve maliyet aşımına neden olan faktörler; işveren kaynaklı, yüklenici kaynaklı, danışma kurulu kaynaklı, malzeme ve ekipman kaynaklı, işgücü kaynaklı, sözleşme ve mevzuat kaynaklı, proje ekibi kaynaklı, dış etkenler ve diğer kaynaklı başlıklar altında belirlenmiştir ve bu faktörlerin proje başarısına olan etkisinin ölçümü hedeflenmiştir. Proje başarısı; süre, maliyet ve kapsam kavramlarının etkileri ölçülerek değerlendirilmiştir.
Yapılan analizler sonunda, tüm faktörlerin proje başarısı üzerinde etkili olduğu görülmüştür. Süre ve maliyet aşımına sebep olan faktörlerin birbirleri üzerinde de etkili oldukları ve hem dolaylı hem de doğrudan süre ve maliyet aşımına sebep oldukları analizlerle desteklenmiştir. Kamu binalarının restorasyon sürecinde süre ve maliyet artışlarını etkileyen faktörler içinde öne çıkanlar: yüklenici kaynaklı sebepler, sözleşme ve mevzuat kaynaklı sebepler, dış etkenler ve diğer kaynaklı sebeplerdir. Anket katılımcılarının demografik dağılımının ise faktörler üzerinde anlamlı ölçüde farklılık göstermediği görülmüştür. Çalışma, süre ve maliyet yönetiminin KRP'nin başarısı için temel belirleyiciler olduğu sonucuna varılmıştır. KRP ile ilgili literatüre ve Türkiye'deki mevcut süre ve maliyet artış sebepleri üzerine ayrıntılı bilgiler içeren bu tez çalışmasının, gelecekteki çalışmalar ve KRP için geçerli bir kaynak olması amaçlanmıştır.

Anahtar Kelimeler: Kamu restorasyon projeleri, süre yönetimi, maliyet yönetimi, süre ve maliyet performansı

Abstract:
This dissertation focuses on the time and cost overruns of public restoration projects in Turkey. As of the end of 2018, 5250 immovable cultural assets registered with The Directorate General of Foundations have been restored in Turkiye and the country allocates significant resources for public restoration. Although the resources allocated to public restoration projects from the country's budget are high, the fact that the number of academic studies in this field is quite low which shows the original value of this study. The objective of this thesis is to identify the factors that contribute to time and cost overruns in the restoration of public buildings, to examine the interrelationships between these factors, and to interpret the findings in order to develop strategies for reducing time and cost overruns in the future. It is aimed that this study will be used as a source in the future and lead to more detailed research. The thesis study encompasses a range of research methods, including literature research, semi-structured interviews, a questionnaire study, and the analysis of the information obtained through these methods.
At the very beginning of the research 20 public restoration project documents have obtained from contractors. According to the documents 14 of 20 projects exceeded its time limitations, also cost overrun observed in 10 of these 14 projects. According to this knowledge, projects that run out of time are also likely to experience cost overruns. It is obvious that most of public restoration projects suffer from both time and cost overruns which is the motivation of this thesis to find out ways to lower the probability.
After defining the problem of public restoration projects semi-structured interviews were carried up with 25 professionals of public restoration sector. This group of 25 people consists of contractors, employers, consultants and academics. They were asked about the factors that cause time and cost increases in public restoration projects.
On the other hand, a literature study was conducted about public restoration projects in Turkiye. Due to the lack of sufficient studies in the literature on public restoration, the literature on time and cost overruns in restoration and new construction projects both in Turkiye and in the other countries was also reviewed and grouped.
The factors causing time and cost overruns were grouped into 8 groups by combining the information obtained through semi-structured interviews and literature research. The factors were identified under the following headings: employer related, contractor related, advisory board related, material and equipment related, workforce related, contract and legislation related, project team related, external factors and
other related. The aim was to measure the impact of these factors on the success of the project.
In line with the data obtained, 4 factors measuring the 8 variables were determined and used in the questionnaire. In the questionnaire, respondents were asked to evaluate the factors separately as the observed situation and the expected situation. The questionnaire was sent to 211 people working in the public restoration sector through the online application with the purposeful sampling method and only 47 of them responded. The research was informed by the input of a diverse range of participants, including employees of the General Directorate of Foundations, contractors, architects, civil engineers, field workers, consultants, academicians and other individuals involved in the restoration of public buildings at any stage of the project process.
The 47 questionnaires obtained were analyzed with SPSS 26 program. Descriptive statistics, t test, one-way analysis of variance, TUKEY test, correlation analysis and regression analysis were used in the study.
Upon conclusion of the analysis, it was determined that all factors had a direct impact on project success. All these factors often trigger each other, leading to time and cost overruns. Project success was evaluated by the participants based on the concepts of duration, cost and scope. The most significant factors contributing to time and cost overruns in PRP can be classified into the following categories: contractor-included reasons, contractual and legislative reasons, external factors and other reasons included.
It is seen that the level of agreement with the impact of the factors affecting the success of public restoration projects does not vary significantly according to the participants' years of experience for both the current situation and the expected situation. For this reason, it is seen that those working in the public restoration sector have similar views regardless of their experience level.
The most important factor that causes time and cost overruns in the restoration process of public buildings is the change in the scope of the project. With the change in the scope of the project, new productions may arise, which directly causes time and cost overruns. Unlike new construction, restoration projects involve more uncertainties than new construction, so many unexpected things may occur during the construction phase of the public restoration projects.
The most important source of these uncertainties is inadequate preparatory work before construction. Inadequate preparatory work in the early stages of public restoration projects leads to a change in scope during the construction phase of the project, which is the most important reason for time and cost overruns.
Existing legislation and laws also have an impact on the cost and time overruns in the public restoration projects. The existing process leads to time and cost overruns, so it is important that the laws and regulations applicable to public restoration projects are updated to include the elimination of existing problems.
During the implementation process, factors such as material supply, labor continuity, financial resource transfer, weather conditions fundamentally affect the project implementation process. If each expert can fulfill his/her duties in a complete and fully disciplined manner, the construction process will progress much healthier, faster and more successfully.
It has been observed that factors such as the selection of appropriate methods, the use of appropriate materials, and proper planning and management are vital for the success of restoration projects. Proper organization of the implementation process is critical to shorten project duration and reduce costs, efficiency in the public restoration projects can be achieved through proper planning, resource management and the effective use of technological innovations.
Considering the data in the thesis, it is seen that the studies to be carried out on this subject will be very useful for the public restoration sector and it is especially important in terms of more efficient use of public resources. With this and future researches, cost and time overruns in Turkish Public Restoration Construction Projects can be reduced.

Key Words: Public restoration projects, time management, cost management, time and cost performance