Stochastic Seismic Analysis of a Cable-Stayed Bridge Using CFRP Cables

Fiber reinforced polymer (FRP) composites have found increasingly wide applications in civil engineering due to their high strength-to-weight ratio and high corrosion resistance for last two decades. This paper presents a numerical study on the stochastic seismic analysis of a cablestayed bridge subjected to earthquake ground motion using carbon fiber reinforced polymer (CFRP) cables. Jindo Bridge is chosen and schemed using CFRP cables. The cross-sectional areas of CFRP cables are determined by the principle of either equivalent cable stiffness or equivalent cable strength. The analysis of the selected bridge is conducted and the results obtained for CFRP cables are compared with steel counterpart. The results indicate that response values obtained for CFRP cables correspond well with those of the steel cables

Asma Köprülerin Analiz Yöntemleri

Konferans Bildirisi -- Teorik ve Uygulamalı Mekanik Türk Milli Komitesi, 2015Conference Paper -- Theoretical and Applied Mechanical Turkish National Committee, 2015Bu çalışmada, asma köprülerin deterministik ve stokastik dinamik analizleri; geometrik olarak lineer olmayan davranış dikkate alınarak incelenmektedir. Uygulama olarak Boğaziçi Asma Köprüsü seçilmiştir. Yer hareketi olarak 1971 San Fernando depremi Pacoima Barajı S16E bileşeni ile 1992 Erzincan depremi doğu-batı bileşeni ivme kayıtları kullanılmaktadır. Stokastik analizlerde yer hareketini temsil etmek üzere Clough ve Penzien tarafından düzeltilerek elde edilen filtre edilmiş beyaz gürültü modeli dikkate alınmaktadır. Yer hareketi modeli, mesnetlere etkiyen yer hareketlerinin yansıma ve kırılmalarla değişebilir olmasından kaynaklanan korelasyon etkisini, dalga yayılma etkisini ve zemin özelliklerinin yer hareketine etkisini içermektedir. Analizler sonucunda köprü kuleleri ve tabliyesine ait yerdeğiştirme ve kesit tesirleri elde edilmiştir. Yer tabakasının karmaşık yapısından dolayı, yer hareketlerinin farklı noktalardaki değişiminden doğan etkilerin asma köprüler gibi uzun açıklıklı sistemlerin deterministik ve stokastik analizlerinde dikkate alınması gerektiği vurgulanmaktadır.In this study, deterministic and stochastic dynamic responses of suspension bridges are investigated by considering geometrically nonlinear behavior. Bosporus Suspension Bridge is chosen as an example. S16E component of Pacoima Dam record of 1971 San Fernando earthquake and east-west component of 1992 Erzincan earthquake are used as ground motions. Filtered white noise model modified by Clough and Penzien is considered as a ground motion in the stochastic analyses. The ground motion model includes the effects of incoherence, wave passage, and site response. The bridge towers and deck displacement and internal forces are obtained in the end of the analyses. Because of the complex nature of earth crust, it is emphasized that the multiple support seismic excitations should be taken into account in the deterministic and stochastic analyses of long span structures like suspension bridges

Dynamic Analysis of a Suspension Bridge Using CFRP Composite Material

Fiber reinforced polymer (FRP) is a class of advanced composite materials used in civil engineering because of their advantages when these materials are compared to traditional ones. These advantages are light weight, high stiffness-to-weight and strength-to-weight ratios, damping capabilities, and high resistance to environmental degradation. This paper presents a numerical study on the dynamic analysis of a suspension bridge subjected to earthquake ground motion using carbon fiber reinforced polymer (CFRP) materials. Bosporus Suspension Bridge is selected for application. The cross-sectional areas of CFRP elements are determined by the principle of either equivalent-stiffness or equivalent-strength methods. The YPT330 component of Yarımca station records of 1999 Kocaeli Earthquake is chosen as a ground motion. The calculated displacement and internal forces occurring in the towers and deck are examined. It is seen from the analyses results that, CFRP material are more effective than steel material for suspension bridges

Numerical Modeling of Masonry Infilled Reinforced Concrete Building during Construction Stages Using ABAQUS Software

The effects of seismic actions on reinforced concrete (RC) structures are strongly influenced by the dynamic behavior of their materials. It is crucial to find a simple definition of the natural frequencies of reinforced concrete buildings, particularly in relation to both principal and secondary elements constructing the reinforced concrete building type. This paper firstly presents a comparison with the ambient vibration surveys. An analysis model of different stages of construction of the reinforced concrete masonry wall was compared using the finite element software. In the second step, structural responses of the model were investigated by means of static analysis. Three main types were examined: Bare frame for one, two and three storeys; brick-walled; and coated cases. Modal analysis is carried out by ABAQUS software starting from the deformed building, to provide the natural frequencies and mode shapes. For the natural frequencies, a good agreement is obtained between analytical and experimental results. Furthermore, the comparison results between different cases show that the application of the plaster work increases the lateral stiffness and has significant effects on the dynamic response of the buildings

Yakın Ve Uzak Fay Yer Hareketi Etkisindeki Asma Köprülerin Yapısal Davranışlarının Belirlenmesi

Konferans Bildirisi -- Teorik ve Uygulamalı Mekanik Türk Milli Komitesi, 2011Conference Paper -- Theoretical and Applied Mechanical Turkish National Committee, 2011Bu çalışmada, yakın ve uzak fay yer hareketi etkisinde bulunan asma köprülerin yapısal davranışlarının belirlenmesi amaçlanmıştır. Çalışmada örnek olarak, Ülkemizde bulunan iki asma köprüden biri olan Boğaziçi Köprüsü örnek olarak seçilmiştir. Köprünün sonlu eleman modeli proje verileri dikkate alınarak SAP2000 programında oluşturulmuş, analizlerde geometrik olarak lineer olmama durumu dikkate alınmıştır. Köprünün yapısal davranışının belirlenmesinde, 1999 yılında meydana gelen Kocaeli ve Chi-Chi depremlerinin aynı maksimum ivmeye ve yakın-uzakfay özelliklerine sahip ivme kayıtları kullanılmıştır. Analizler sonucunda, tabliye uzunluğu ve kule yüksekliği boyunca yerdeğiştirmeler ve kesit tesirleri elde edilmiş, elde edilen değerler karşılaştırmalı olarak irdelenmiştir. Çalışmadan, yakın fay yer hareketinin yerdeğiştirme ve kesit tesirlerinde uzakfay yer hareketine oranla dahafazla etkili olduğu görülmüştür

On the earthquake-related damages of civil engineering structures within the areas impacted by Kahramanmaraş earthquakes

Two major earthquakes occurred on the Eastern Anatolian Fault Line (EAF) on February 6, 2023, with an interval of nine hours. These earthquakes, measuring Mw 7.7 and Mw 7.6, were centered in the districts of Pazarcık and Elbistan in the province of Kahramanmaraş. They directly affected 11 provinces (Kahramanmaraş, Hatay, Adıyaman, Osmaniye, Gaziantep, Şanlıurfa, Malatya, Diyarbakır, Adana, Kilis, and Elazığ) in the Eastern and Southeastern Anatolia, caused significant loss of life and property. This study aims to present the field investigation and performance evaluation of engineering structures in the mentioned cities. The types of damages occurring in the reinforced concrete (RC) and masonry buildings, historical and industrial structures, bridges, and mosques were given in detail. According to the data of the Ministry of Treasury and Finance of Türkiye, it has been reported that the cost of these earthquakes is approximately 103.6 billion dollars, which corresponds to nine percent of Türkiye's national income expectation for 2023 and causes damage and losses of approximately six times more than the 1999 Marmara earthquake. In the areas affected by earthquakes, many of the errors determined by professionals from previous earthquakes still exist today