FARKLI ZEMİN ORTAMLARINA YERLEŞTİRİLEN ESNEK GÖMÜLÜ BORULARIN DÜŞEY YÜKLER ALTINDAKİ ŞEKİL DEĞİŞİMİMİN DENEYSEL VE AMPRİK YÖNTEMLERLE İNCELENMESİ

Esnek boruların şekil değişimi ve zamana bağlı davranış biçimleri çelik ve betondan malzemelerden üretilen rijit borular ile kıyaslandığında bir çok yönden farklılıklar gösterir. Düşey yükler altındaki deformasyon davranışları; geri dolgu mazlemesi ve yerleştirme koşulları ile doğrudan ilişkilidir. Bu çalışmada 100 mm yarıçapındaki bir HDPE esnek borunun düşey yükler altındaki davranışı labaratuvar ortamında incelenmiştir. Çalışmalarda, deney kutusu, şişebilen membran yastıklar, yağmurlama sistemi, pozisyon ve şekil değişimi ölçerler kullanılmıştır. İnceleme kapsamında farklı zemin ortamları dikkate alınmıştır. Matematiksel analizler için Geliştirilmiş Iowa yöntemini temel alan Masada Derivasyonu kullanılmış ve deney sonuçları ile matematiksel sonuçlar birbirleri ile karşılaştırılmıştır. Yapılan değerlendirmeler sonucunda geri dolgu malzemesinin boru davranışında önemli bir etken olduğu görülmüş, Masada Derivasyonunun boru dayanımının kestiriminde güvenilir çözümler ortaya koyduğu saptanmıştır.

Anahtar Kelimeler:

HDPE gömülü boru, Labaratuvar testi, Masada derivasyonu formülü.

EXPERIMENTAL AND NUMERICAL INVESTIGATION OF FLEXIBLE BURIED PIPE DEFORMATION BEHAVIOR UNDER VARIOUS BACKFILL CONDITIONS

Deformation characteristics of polyethylene based flexible pipes are different than rigid pipes such as concrete and iron pipes. Deflection patterns and stress-strain behaviors of flexible pipes have strict relation between the engineering properties of backfill and its settlement method. In this study, deformation behavior of a 100 mm HDPE flexible pipe under vertical loads is investigated in laboratory conditions. Steel test box, pressurized membrane, raining system, linear position transducers and strain gauge rosettes are used in the laboratory tests. In order to analyze the buried pipe performance; Masada Derivation Formula which is mostly used by designers is employed. According to the test and mathematical studies, it is understood that relative density of backfill and its settlement method is a considerable effect on buried pipe performance and Masada Derivation method is very efficient for predicting the pipe performance.

Keywords:

HDPE buried flexible pipe, Laboratory test, Masada derivation formula.,

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