M.Sc. Tezi Görüntüleme

Student: Hakan ÖZMEN
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: Modeling of Blast-induced Ground Motion and Their Effect on Above-Ground Structures
Level: M.Sc.
Acceptance Date: 17/4/2006
Number of Pages: 73
Registration Number: i1680
Summary:

      Today, there is a rapidly increasing use of explosives as a facilitating method in many engineering practices, principally in stone quarries, mining sector, tunneling works on rock grounds and demolition of old buildings in the city. Therefore, their possible environmental effects should be known well.

In this study, first the characteristic acceleration–time changes of ground vibrations created by using various explosives have been determined by finite element method according to the single chamber single explosion ground model. Then, the effect of earthquake and blast-induced ground motion on the behavior of two and higher freedom degree systems has been comparatively studied. Finally, damage levels have been determined using blast-induced acceleration changes computed for various three-dimensional types of structures.

      Parallel to findings obtained from this study, it was seen that peak value high frequency ground motions have occurred in short distances in the ground environment as a result of explosion, and the maximum value has rapidly decreased with the reduction of explosive amount or increase of distance. It was also determined that the dynamic behavior of ground motions in remote distances harmonized with sinus distribution. It was seen that the vertical component of ground motion was effective in short distances and its horizontal component in remote distances.

It was understood, for the purpose of structural analysis under blast-induced ground motions or similar high frequency dynamic influences, that modeling is required, considering higher modes followed by basic modes. It was observed that crack-level damage occurred in structures in high frequency ground motions. It has been noted that crack formation in walls surrounded by columns has decreased in comparison with those not surrounded, that crack formations in high-storey frame structures were higher on first floors and that crack formation may be at its highest in stack structures.

      Key words : Blast, Blasting Ground Motion, Structural Damage