Ph.D. Tezi Görüntüleme

Student: Murat Emre KARTAL
Supervisor: Prof. Dr. Alemdar BAYRAKTAR
Department: İnşaat Mühendisliği
Institution: Graduate School of Natural and Applied Sciences
University: Karadeniz Technical University, Turkey
Level: Ph.D.
Acceptance Date: 4/6/2010
Number of Pages: 152
Registration Number: Di772

      In this thesis, reliability analyses of concrete-faced rockfill dams under static and earthquake are performed considering dam-foundation-reservoir interaction. The effect of reservoir water on dam is considered using fluid finite elements based on the Lagrangian approach. Welded and friction contact are considered in various joints. One dimensional surface-to-surface contact elements obeying Coulomb’s friction law are used for frictional contacts. Earthquake response of the dam to deconvolved ground acceleration record is obtained. Non-reflecting boundary conditions are defined by viscous dampers. Drucker-Prager model is used for concrete and multi-linear kinematic hardening model is used for rockfill in the materially nonlinear analyses. Geometrically nonlinearity is also considered.

FERUM, reliability analysis program, is combined with ANSYS finite element program in the reliability analysis of concrete-faced rockfill dam. The needed values used in the implicit limit state function are obtained by the established connection between these programs. Improved Rackwitz-Fiessler Method is used with Direct Coupled Method and Response Surface Method in the reliability analysis of the dam under static loads and used with Response Surface Method in the reliability analysis of the dam to earthquake. The probability of failure is computed for the selected critical points in the concrete slab.

      This thesis is composed of four chapters. In the first chapter, literature researches, used methods and formulations are given. In the second chapter, numerical model of the concrete-faced rockfill dam is given and the reliability analysis algorithm is explained. In the third chapter, initially, earthquake response of the dam is examined and then reliability of the dam under static and earthquake loads is studied. In the last chapter, it is deducted from the study that reservoir water decreases the reliability of the concete slab and to consider friction in the joints increases the reliability of the concete slab and in addition to this the proposals for further studies are given. This chapter is followed by the references.

Key Words : Dam-foundation-reservoir interaction, Drucker-Prager model, Probability of failure, Reliability analysis, Multi-linear kinematic hardening model, Lagrangian approach, Nonlinear response, Concrete-faced rockfill dam, Frictional contact, Contact elements.