Seismic plastic–damage analysis of mass concrete blocks in arch dams including contraction and peripheral joints. Issue 95 (April 2017)

• Record Type: Journal Article
• Authors: Omidi, Omid; Lotfi, Vahid
• Is Part Of: Soil dynamics and earthquake engineering. Issue 95(2017)
• Page Start: 118
• Page End: 137
• Publication Date: 2017-04
• Subjects: Plastic–damage -- Discrete crack -- Contraction joints -- Concrete arch dam -- Dam–water interaction -- Peripheral joints; Soil dynamics -- Periodicals; Earthquake engineering -- Periodicals; Sols -- Dynamique -- Périodiques; Génie parasismique -- Périodiques; 624.176205
• DOI: 10.1016/j.soildyn.2017.01.026
• Languages: English
• ISSNs: 0267-7261

Abstract

Abstract: Seismic nonlinear analysis of concrete arch dams is a topic having been extensively studied in the last two decades. Due to the existence of different joints within the body of arch dams, the discrete crack (DC) approach utilizing interface elements for the joints is the most realistic method. In fact, it could be the first step to assess the seismic safety of an arch dam. Furthermore, since the mass concrete blocks may crack due to severe ground excitations, a plastic–damage (PD) model well capturing stiffness degradation and permanent deformation due to tensile cracking and compressive crushing might be needed. In this study, a special finite element program called SNACS is developed based on the combined discrete crack and plastic–damage (DC–PD) technique. The dam–reservoir interaction as an important factor affecting the seismic response of arch dams is also treated by the Lagrangian–Eulerian formulation. The joints modeling strategy adopted herein is addressed first and then, a brief review of the plastic–damage model proposed by Lee and Fenves and extended herein to 3-D space is presented. Afterwards, the nonlinear seismic analysis of a typical thin arch dam is performed based on the combined approach and the response is compared with the results of each method. It is emphasized that employing the combined DC and PD models gives more reliable and consistent response in comparison with using DC or PD approaches applied alone. Therefore, the DC–PD technique could be considered as a major step toward a more accurate seismic safety evaluation of concrete arch dams. Abstract : Highlights: Damages in middle cantilevers will remarkably be increased due to joints opening. Multi-axial stress states governed in mass concrete blocks lead to shear damages. Cracking zones were found to be influenced by the dam-water interaction solution. Damage-dependent damping severely affects cracking zones in mass concrete blocks. The DC-PD technique is proved to be essential for a safety assessment of arch dams.