Effect of Imperfections in FEM Modelling on the Seismic Performance Assessment of Liquid Storage Tanks

Abstract

Fluid-structure interaction (FSI) algorithms of the finite element method (FEM) is employed to evaluate the seismic response of three dimensional (3D) atmospheric tanks containing fluid under seismic loading by taking into account sources of nonlinearity of tanks. Numerical analysis model was generated both design drawing data and point cloud data obtained from 3D Laser Scan Process. All FEA Model was analysed and evaluated by performing dynamic time-history analysis under multi-dimensional. Fluid-structure interaction (FSI) was modelled with SPH technique. 5 pairs of horizontal ground motion time history components (two horizontal components for each ground motion record orthogonal to each other and vertical ground motion) was selected complying with near fault distance and frequency content of motion. Influence of imperfection in FEM modelling was evaluated in terms of seismic failure mechanism.

Keywords

• Atmospheric Tank
• 3D Laser Scan
• Finite Element Method
• Fluid-Structure Interaction
• SPH Modelling

Sonlu Elemanlar Modeli Anomaliliklerinin Sıvı Depolama Tanklarının Sismik Performans Değerlendirmesine Etkisi

Abstract

Tank-sıvı etkileşiminin doğrusal olmayan (nonlineer) davranış kaynaklarını göz önüne alabilen sonlu elemanlar yöntemi (FEM) kullanılarak, sıvı ihtiva eden üç boyutlu atmosferik tankların deprem yükleri altında doğrusal olmayan davranışları incelenmiştir. Sayısal analiz modeli hem tasarım çizim verileri hem de üç boyutlu (3D) Lazer Tarama sonucu elde edilen nokta bulut verileri ile hazırlanmıştır. Sismik performans değerlendirmesi her iki farklı model tipi için üç doğrultulu zaman tanım alanı analizleri ile gerçekleştirilmiştir. Yapı-sıvı etkileşimi SPH (Smoothed Particle Hydrodynamics) metodu tekniği ile modellenmiştir. Sismik analizlerde deprem yer hareketleri fay mesafelerinin yakınlığı ve kayıt frekans muhtevasına göre seçilmiştir. İki farklı modelleme yaklaşımının karşılaştırılması sismik hasar mekanizmaları üzerinden değerlendirilmiştir.

Keywords

• Amosferik Tank
• 3D Lazer Taraması
• Sonlu Elemanlar Metodu
• Yapı-Sıvı Etkileşimi
• SPH Modelleme

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