Sürdürülebilir Kalkınma Amaçları
Yazarlar
Yayınlar
- MakaleYalnız künye2023Influences of Wall Configurations on Earthquake Behavior of Cantilever Retaining Walls Considering Soil-Structure Interaction Effects
Ozturk, Kasif Furkan; Cakir, Tufan; Araz, Onur
Cantilever walls are frequently and necessarily built not only in earthquake prone regions but also on different foundation subsoils with various physical and mechanical characteristics. The response of these structures is a complicated soil-structure interaction (SSI) problem, in which the relative stiffness between the soil and structure is of critical importance. In addition to different soil conditions and earthquake motions, the wall configurations have an important role in the cantilever retaining wall design. Thus, the major objective of this work is to investigate the effects of various configurations on seismic response of the cantilever retaining walls considering SSI. Accordingly, the seismic response of the interaction systems is revealed using the 3D finite element models (FEM) in time domain, assuming linearly elastic behavior for the wall, and elastoplastic behavior for backfill and foundation soil. Viscous absorbent boundaries are employed to both simulate radiation scenario and avoid undesirable wave reflections generated by soil lateral boundaries. Backfill-wall interfaces are modeled using the unidirectional interface elements with nonlinear force-deflection abilities. The interaction systems are analyzed considering three different cantilever wall configurations (inverted T-type, L-type, and the wall with a base key), four different ground motion records, and four different subsoil systems. Nonlinear seismic analyses are carried out to visit how considering the variation of these parameters influences the wall behavior. The results from parametric studies show that the wall configuration, SSI effects and ground motions are remarkably influential on seismic responses of the cantilever walls such as the stresses and horizontal displacements.
- Yüksek Lisans TeziAçık Erişim2015Afet bilinci ve kader ilişkisi: Gümüşhane örneği
Mazhar Oyanık
Afet; bir toplumu derinden sarsan, ciddi can ve mal kayıpları yaşatan doğal veya insan kaynaklı olaylardır. Ülkemizde meydana gelen çeşitli afetlerden dolayı içinde bulunduğumuz coğrafyada insanlar sürekli afet riski altındadır. Toplumun dini inancı gereği afetlerin meydana gelme sebebi bazıları tarafından kader olarak değerlendirilir. Ancak tüm yaşanan felaketler kader olsa bile dinimizin öğretisi sırtımızı kadere yaslamak değil tedbirli olmayı göstermektedir. Bu bağlamda bölgemizde gerçekleşen afetlerin çeşitliliği ve sıklığı sebebiyle afet öncesi, sırası ve sonrası yapılacak faaliyetleri bilmek ve daima afet bilincine sahip birey olmak toplumun geleceği için önemlidir. Bu araştırma, Gümüşhane'de yaşayan bireylerin afet konusunda bilgi ve bilinç düzeyleri ile kader inançları arasındaki ilişki düzeyleri ve afete ne kadar hazır oldukları üzerinedir. Çalışmamız Gümüşhane ilinde ikamet eden 385 kişi ile yüz yüze yapılan görüşmelerde afet bilinci ile kader inançları arasındaki ilişki kavranmaya çalışılarak, kader inancının afet bilinç düzeylerini ne derece etkilediği ve katılımcıların ne düzeyde afet bilincine sahip oldukları ölçülmeye çalışılmıştır. Afet bilinci ile kader ilişkisi, sorulan üç soruda tespit edilmiş olup genel anlamda bir ilişki tespit edilememiştir. Elde edilen bulgular SPSS 20 paket programında analiz edilerek yorumlanmaya çalışılmıştır. Anahtar Kelimeler: Afet, Afet Bilinci, Kader, Afet Bilinci ile Kader İlişkisi
- MakaleYalnız künye2011Finite element model calibration effects on the earthquake response of masonry arch bridges
Sevim, Baris; Bayraktar, Alemdar; Altunisik, Ahmet Can; Atamtürktür, Sezer; Birinci, Fatma
The focus of this paper is to illustrate the importance of model calibration and in situ vibration testing by comparing the finite element model predictions of the earthquake response of the two historical arch bridges, Osmanli and Senyuva, before and after model calibration. The three-dimensional finite element models of these two arch bridges, built in the ANSYS finite element program, are used to predict bridge dynamic characteristics, such as natural frequencies and mode shapes. Following the analytical study, ambient vibration tests were conducted to experimentally obtain dynamic characteristics of these two bridges. During ambient vibration tests, accelerometers were placed at several points on the bridge to collect the vibration response due to natural and operational excitation sources. Enhanced frequency domain decomposition and stochastic subspace identification techniques were used to extract the experimental natural frequencies, mode shapes and damping ratios. Finite element models of the two arch bridges were adjusted such that the model predictions reproduce the ambient vibration test results with increased fidelity. The behavior of the masonry arch bridges under earthquake excitation recorded during the Erzincan Earthquake in 1992 is simulated by both the initial and adjusted finite element models. The findings of this study emphasize the importance of model calibration and ambient vibration testing. (C) 2010 Elsevier B.V. All rights reserved.
