Ph.D. Tezi Görüntüleme

Student: Durdu Mehmet ÖZCAN
Supervisor: Prof. Dr. Alemdar BAYRAKTAR
Department: İnşaat Mühendisliği
Institution: Graduate School of Natural and Applied Sciences
University: Karadeniz Technical University, Turkey
Title of the Thesis: Determination of the Blast-Induced Nonlinear Behavior of Structures Using Experimental Methods
Level: Ph.D.
Acceptance Date: 27/12/2010
Number of Pages: 133
Registration Number: Di813

      In this thesis, it is aimed to determine the nonlinear behavior of structures considering the blast-induced ground motion using experimental methods. For this purpose, a reinforced concrete building, a masonry building, a reinforced concrete bridge, and a masonry bridge are selected, blasting data are attained from the ground during the blasting and experimental vibration signals obtained from the structures. A total of 64 blasting data are used to develop the blast induced damage criteria. Dynamic characteristics such as natural frequencies, mode shapes and damping ratios are obtained using Operational Modal Analysis method. Three dimensional finite element models of the structures are constituted using ANSYS software and dynamic characteristics are obtained analytically. Finite element models of the structures are updated according to the experimental results using some uncertainty parameters such as material properties and boundary conditions. Nonlinear dynamic behaviors of the structures are determined using blast induced ground motion records. Drucker-Prager material model is considered in the nonlinear analysis.

This thesis is composed of four main chapters. In the first chapter, literature researches, damage criterias used foreign countries and formulations are given. In the second chapter, experimental measurements obtained from the ground and structure are given and modal analyses of the structures are carried out. In the third chapter, damage criteria are determined, finite element models of the structure are updated and nonlinear dynamic behaviors are determined using blast induced ground motion records. In the last chapter, the conclusions deducted from the study and the suggestions for further studies are presented. This chapter is followed by the references and backround.

      Key Words : Dynamic characteristic, Nonlinear behavior, Drucker-Prager model, Damage criteria, Operational Modal Analysis, Blast induced ground motion, Finite element model updating.