Abstract

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2007 Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2007 Bu çalışmada ilk bölümde demiryolu üstyapısı ve üstyapıyı oluşturan elemanlar incelenmiştir. Ray, travers, balast ve bağlantı malzemeleri ve demiryolu üstyapısı içindeki işlevleri anlatılmıştır. Geçmişten günümüze üstyapı elemanlarının kısaca gelişimine değinilmiş, günümüzde kullanılan yeni tipleri tanıtılmıştır. İkinci bölümde İstanbul’da kent içi raylı sistemler incelenmiş ve mevcut, yapım aşamasında ve proje safhasında olan hatlar tanıtılmıştır. Üstyapıları bilinen mevcut hatlar, Aksaray-Havalimanı Hafif Metro Hattı, Kabataş-Zeytinburnu Cadde Tramvayı, Taksim-4.Levent İstanbul Metrosu tanıtılmış, üstyapıları incelenmiştir. Üstyapı tipleri kesinleşmemiş yapım ve proje aşamasında hatların üstyapılarına değinilmemiş, genel olarak tanıtımları yapılmıştır. Üçüncü bölümde demiryolu üstyapı hesapları anlatılmış ve mevcut raylı sistemlerin üstyapı hesabı yapılmıştır. Bu hesaplarda Winkler’in elastik ortama oturan kiriş hipotezi baz alınmıştır. Bu hipotezi demiryolu üstyapısı hesabında kullanırken Zimmerman yöntemi takip edilmiştir. Üstyapı hesabında statik yükler için bulunan sonuçlara dinamik etkilerin katılmasında Eisenmann’ın geliştirdiği Münih Teknik Üniversitesi Karayolları ve Demiryolları İnşaatı Enstitüsü’nün verdiği üstyapı biçimine ve hıza bağlı formulasyonlar kullanılmıştır., Bulunan dinamik değerler neticesinde mevcut üstyapıların yeterli oldukları tahkikler sonucunda bulunmuştur. In this study, railway superstructure and the superstructure components constituting the superstructure are examined. Rail, sleeper, ballast and fastenings and their functions in railway superstructure are explained. The development of these superstructure components through the history is mentioned and the new types which are used today are introduced. In the second section, railway systems of Istanbul are examined and the current tracks, the tracks under construction and the ones in the phase of planning are introduced. The current tracks with known superstructure, Aksaray – Airport Line, Kabataş – Zeytinburnu Tram, Taksim - 4. Levent İstanbul Subway are introduced and their superstructures are examined. The superstructure features of the tracks with indefinite superstructure types which are under construction or in the phase of planning are not mentioned, only general presentations of them are annexed. In the third section, superstructure calculations of railway systems are explained and the superstructure calculations of current railway systems are computed. In these calculations, Winkler s hypothesis about the joist fitting upon an elastic ground is taken as the main basis. When applying this hypothesis to the calculation of railway systems superstructure, Zimmermann method is followed. For consolidating the dynamic factors with the results about the static loads in the calculation, the formulations which depend on the type of the superstructure and speed and which are developed by Eisenmann and given by Munich Technical University Highways and Railways Construction Institute are used. The current superstructures are investigated in the light of the calculated dynamic values and are proven to qualified. Yüksek Lisans M.Sc.

Abstract

With the help of Under Sleeper Pads (USP) a further step towards a sustainable, and durable superstructure in railway engineering can be achieved. The development of USP within the classic components used in the construction of permanent ways can bring defined elasticity into the track. They are installed on the bottom surface of the sleeper and thereby increase the degree of vertical elasticity in the track superstructure. The objective is to transmit the loads from the vehicles through the rails, rail fasteners and the sleepers into the superstructure and the subgrade in the smoothest, safest and most evenly distributed manner possible. With the use of USP not only the bending line of the rail is activated and the load is distributed to more sleepers but also the contact area of the sleepers with the ballast is widely increased – and vibrations can be mitigated. A normal concrete sleeper shows a contact area of around 2-8% of the sleeper’s bottom area towards the ballast meanwhile the use of polyurethane USP show up to 35 % contact area. Therefore, next to other positive effects, ballast wear will be reduced in a great manner and looking on the sustainability and life cycle analysis the tamping cycles can be reduced up to 2.5 times. Looking back on more than 25 years of USP in track, turnouts and transition zones for ballast protection, improved track stability or vibration isolation, a vast number of projects are evaluated and the long term benefits can be seen in tracks all over the world."br" With the ongoing development of new materials and improvements of the existing products the technology of Under Sleeper Pads is up-to-date and ready to react on upcoming challenges.