Akköprü barajı’nın hesaplanan ve gözlenen deformasyon davranışı
Bu çalışmada, kil çekirdekli kaya dolgu tipteki, 162.50 m. yüksekliğe sahip Akköprü Barajı’nın inşaat ve su tutma aşamalarındaki deformasyon davranışı incelenmiştir. Oluşan yer değiştirmelerin belirlenmesi amacıyla, iki boyutlu düzlem şekil değiştirme prensibi kullanılarak sonlu elemanlar analizleri gerçekleştirilmiştir. Kaya dolgu malzemenin doğrusal ve elastik olmayan, gerilme bağımlı davranışını temsil etmek için sertleşen zemin modeli kullanılmıştır. Malzeme sonlu eleman model parametreleri, kil çekirdek malzemesi için üç eksenli basınç deney sonuçlarından, diğer malzemeler için ise önceki çalışmalar temelinde seçilmiştir. İnşaat sonrasına ait hesaplanan ve ölçülen deformasyonlar, büyüklük, zamanla değişim ve baraj gövdesindeki konumları itibarı ile uyumludur. En büyük oturma baraj gövde yüksekliğinin yaklaşık yarısında ortaya çıkmıştır. Su tutma aşamasındaki davranış da değerlendirilmiş, oluşması beklenen oturmalar için tahminlerde bulunulmuştur.
Predicted and observed deformation behavior of Akköprü dam
In this study, the settlement behavior of Akköprü Dam, which is a 162.50 m high rockfill dam with clay core, is investigated for the end-of-construction and reservoir impoundment stages. Finite element analyses that are based on a 2-D plain strain solution are performed to determine the displacements. Hardening soil model is used to represent the non-linear, inelastic, and stress-dependent behavior of rockfill. Material model parameters for clay are selected from triaxial compression test results. For other materials, preliminary values for model parameters are chosen based on the results from previous studies on dams. Predicted and measured displacements are in agreement as a function of time, in terms of magnitude and location for the end-of-construction stage. The maximum settlement is observed to be approximately at the middle of the dam height. Predictions are also made for the displacements for reservoir impoundment conditions.
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- ISSN: 1300-3453
- Yayın Aralığı: 6
- Yayıncı: TMMOB İnşaat Mühendisleri Odası