The Effects of Track Stiffness on Track Performance

Öz

Required stiffness value for a railway track must determined within the safety limits and it should reduce maintenance costs. While track must be stiff enough to conserve track’s geometric qualities, it must also provide sufficient flexibility in order to provide proper load distribution and avoid wear in track components. While determining this value, effects of the track stiffness on the track design parameters that influence track performance such as track deformations, pressure and strains must be taken into consideration.

In this work, variation of the parameters that influence track performance with respect to the change of track stiffness is examined. Problems faced in tracks with very high stiffness or very low stiffness are discussed. Therefore, importance of the determination of optimum stiffness value that provides maximum safety, minimum maintenance cost and long service life is shown.

Anahtar Kelimeler

• Track modulus,Track stiffness,Winkler model,Track performance

Hat Esneme Direncinin Hat Performansı Üzerindeki Etkileri

Öz

Bir demiryolu hattının sahip olması gereken esneme direnci değeri, hattın güvenli hizmet vermesini sağlamakla birlikte hattın bakım maliyetini de azaltacak şekilde belirlenmelidir. Hattın geometrik özelliklerini korumak için hat esneme direnç değerinin yüksek olması istendiği gibi, uygun yük dağılımını sağlamak ve hat bileşenlerinin yıpranmasını önlemek amacıyla bu değerin azaltılması gerekir. Bir bütün olarak hattan en fazla verimin alınabilmesi için en uygun esneme direnci değerinin seçilmesi gerekir. Bu değerin seçiminde, esneme direncinin hat performansını etkileyen ray sehimleri, basınç ve gerilmeler gibi unsurlar üzerindeki etkileri göz önünde bulundurulmalıdır.

Bu çalışmada hat esneme direncinin değişmesiyle hat performansını etkileyen parametrelerin değişimi incelenmiştir. Çok yüksek ve çok düşük esneme direnci değerleri altında karşılaşılan sorunlar ele alınmıştır. Böylece en yüksek güvenlik, en az bakım maliyeti ve en uzun hizmet ömrünü sağlayan bir esneme direnç değeri seçilmesinin önemi ortaya konulmuştur. Son olarak, belirlenen esneme direnci değerinin uygulamada sağlanabilmesi için yapılan çalışmalara yer verilmiştir.

Anahtar Kelimeler

• Hat modülü,Hat esneme direnci,Winkler modeli,Hat performansı

Kaynakça

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