Toprak Barajlardaki Plastik Noktaların Dağılımının Su Seviyesi, Banket ve Deplasmanına Göre Sayısal Analizi

Yıl 2022, Cilt: 4 Sayı: 1, 1 - 15, 30.06.2022

Abolfazl Asadi

Öz

Toprak barajların sismik koşullar altında çökmesi oldukça yıkıcı ekonomik hasarlara ve can kayıplarına neden olabilir. Bu nedenle sismik güvenlik değerlendirmesi ve sayısal analizlerin etkin bir şekilde yapılması gerekmektedir. Bu makale, toprak barajların plastik noktalarının dağılımının sonuçlarını sunmaktadır. Plastik noktaların analizi, göçme öncesi koşullarda toprak barajın gövdesindeki plastikleşme değişimlerini gösterir. 10 m yüksekliğinde dik kil çekirdekli homojen olmayan bir dolgu, PLAXIS 2D yazılımı kullanılarak harmonik ve statik mod dikkate alınarak üç farklı su seviyesinde incelenmiştir. Suyun varlığı yapıdaki plastik nokta sayısının artmasına ve yer değiştirme miktarının artmasına neden olmaktadır. Sonuç olarak, plastik noktaların durumunu ve maksimum yer değiştirmelerin görünümünün yerini değiştirir. Birinci, ikinci ve üçüncü modlarda plastik nokta sayısı 26, 47 ve 116'dır. Ayrıca birinci, ikinci ve üçüncü modlarda maksimum yatay yer değiştirme miktarı sırasıyla 72, 97 ve 227 mm'dir.

Anahtar Kelimeler

Sayısal analiz, Plastik noktalar, Toprak Baraj, Su Seviyesi, Banket

Numerical Analysis of the Distribution of Plastic Points in the Earth Dams Concerning the Water Level, Berm, and Displacement

Öz

Failure of earth dams under seismic conditions may cause disastrous economic damage and loss of lives. Therefore, it is necessary to conduct a seismic safety evaluation and numerical analysis effectively. This paper presents the results of the distribution of plastic points of earth dams. The analysis of plastic points shows the plasticize variations in the body of the earth dam in pre-failure conditions. An inhomogeneous embankment with an upright clay core, which is 10 m high, was studied in three different water levels considering harmonic and static mode using the PLAXIS 2D software. The existence of water causes increasing the number of plastic points in the structure and increasing the amount of displacement. As a result, it changes the situation of plastic points and the location of the appearance of the maximum displacements. The number of plastic spots in first, second and third modes are in order 26, 47 and 116. Also, the amount of maximum horizontal displacement in first, second and third modes are in order 72, 97 and 227 mm.

Anahtar Kelimeler

Numerical analysis, Plastic points, Earth dams, Water level, Berm

Kaynakça

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