Efficiency of Transmitting Boundaries on Dynamic Response of Soil- Structure Interaction Systems

In this study, efficiency of transmitting boundaries which is one of the local procedures is investigated for dynamic analysis of the soil-structure interaction systems and the results are compared with traditional boundaries. Sarıyar concrete gravity dam is chosen for an application. For the soil-structure interaction system of the chosen dam, two different finite element models are prepared. In the first model, the infinite soil media on which the dam has been built is classically represented with finite size using traditional boundaries. In the second model, the infinite soil region is represented with finite size using transmitting boundaries. Dynamic analysis of these soil-structure interaction systems are performed with a computer program for approximate 3-D analysis of soil-structure interaction problems (FLUSH). As a result of the analyses, spectrums of acceleration, velocity and displacement are obtained for crest point of the dam

Çeşitli Sinir Şartlarina Sahip Elastik Kirişlerin Hareketli Yük Etkisi Altinda Dinamik Analizi

Konferans Bildirisi -- Teorik ve Uygulamalı Mekanik Türk Milli Komitesi, 2008Conference Paper -- Theoretical and Applied Mechanical Turkish National Committee, 2008Bu çalışmada, sabit hızla hareket eden tekil yük etkisi altındaki Euler-Bernoulli kirişlerinin değişik sınır şartları için dinamik analizleri yapılmıştır. Kirişlerin hareketli yük etkisi altındaki davranışı analitik ve sayısal metotlar kullanılarak elde edilmiş ve yük hızının dinamik davranış üzerindeki etkileri incelenmiştir.In this study, dynamic analyses of Euler-Bernoulli beams to a moving force with constant speed for various boundary conditions are carried out. The dynamic responses of beams are obtained by using an analytical and a numerical method and effects of the load speed on the dynamic behavior are studied

Seismic analysis of arch dams subjected to in-phase and anti-phase ground motions

In this study, the response of arch dams is obtained for in-phase and anti-phase ground motions when there is no water in the reservoir. The material of the dam is considered to be linearly elastic, homogenous and isotropic. The foundation and banks of the dam, which are usually of hard rock, are assumed to be rigid. The S16E component of San Fernando Earthquake, February 9, 1971, has been used in the calculations. The response of arch dams determined for anti-phase dynamic effects is compared with that of in-phase (uniform) dynamic effects

Shear strain related non-linear stochastic dynamic analysis of rock-fill dams

The effect of the non-linear material behavior of a rock-fill dam subjected to random loads is investigated by the equivalent linear method that considers the non-linear variation of soil shear moduli and damping ratios as a function of shear strain. The Keban dam constructed in Elazığ, Turkey is chosen as a numerical example. The interaction of the rock-fill dam with the reservoir is neglected, but not the foundation rock. The properties of the dam materials were taken from the dam project and assumed to be isotropic in the analysis. A stationary and ergodicity assumption are made for stochastic dynamic analysis. The E-W component of the Erzincan earthquake recorded on March 13, 1992, Erzincan, Turkey is chosen as a ground motion since it occurred nearby the dam site. The component considered is applied to the dam in the horizontal direction. The non-linear stochastic responses of the Keban dam are compared to its linear stochastic and deterministic response

Modal response identification of a highway bridge under traffic loads using frequency domain decomposition (FDD)

In this study, a four-span, 224m long, post-tensioned concrete box girder bridge supported on single column piers was subject to a series of controlled vehicle tests. Bridge acceleration response datasets were used to study the effect of truck speed and a sudden stop, on the modal identification of the bridge structure. Natural frequencies and mode shapes of the bridge were determined using the frequency domain decomposition technique for all datasets. The passing of the truck rendered difficult to identify the first bridge frequency. Conversely, the vehicle tests improved the identification of higher vibration modes. This is because the truck preferentially excites the bridge vertical response, which is associated with higher modes of vibrations, especially when a sudden stop of the vehicle occurs. Thus, carefully conducted vehicle-crossing tests provide detailed information about the bridge structure dynamics in the vertical direction. However, to identify lower modes, no vehicle on the bridge is preferred

Pounding response between rc buildings with equal heights and different dynamic characteristics considering seismic zone 1 of Turkey

Son meydana gelen depremlerde, aralarında yetersiz derz boşlukları bulunan komşu binaların birbirlerinden etkilendikleri gözlemlenmiştir. Bu etkileşim, çarpışan binaların büyük depremler sırasında ciddi zarar görmelerine veya tamamen yıkılmalarına sebep olabilir. Bu çalışmada, Türkiye’nin birinci deprem bölgesinde, eşit yüksekliklere ve farklı dinamik karakteristiklere sahip komşu betonarme binaların çarpışma davranışları incelenmiştir. Binalar arasındaki çarpışma, literatürde sıkça kullanılan lineer olmayan elastik yay (Hertz modeli) çarpışma modeli ile temsil edilmiştir. Bu çalışmada, ivme kayıtları Türk Deprem Yönetmeliğinde (TDY–2007) birinci derece deprem bölgesi için verilen tasarım spektrumuna göre ölçeklendirilmiştir. Komşu binalar, Türkiye’de çok sık kullanılan üç boyutlu kolon kiriş sistemi olarak modellenmiştir. Komşu binaların çarpışma analizleri SAP2000 program kullanılarak zaman tanım alanında analiz yöntemiyle gerçekleştirilmiştir. Birinci derece deprem bölgesinde, eşit yüksekliklere ve farklı dinamik karakteristiklere sahip komşu betonarme binaların çarpışma analizleri neticesinde çarpışma kuvvetleri elde edilmiştir. Bu çalışmanın sonucunda, TDY–2007’de tanımlanan derz miktarlarının yetersiz olduğu anlaşılmıştır.Interactions between inadequately separated neighboring buildings have been repeatedly observed during earthquakes. These interactions may result in substantial damage or even total destruction of colliding structures during strong ground motions. This study focuses on investigation of pounding response between RC buildings with equal heights and different dynamic characteristics considering Seismic Zone 1 of Turkey. A collision between buildings is represented by a pounding model commonly used in the literature, which is a nonlinear elastic spring (Hertz model). In this study, the considered ground motion records are scaled according to design spectrum given for Seismic Zone 1 in Turkish Earthquake Code 2007 (TEC–2007). Neighboring buildings are modelled as a three-dimensional beam-column system which is a widely constructed building type in Turkey. Pounding analyses of the neighboring buildings are performed in time domain by aid of SAP2000 program. Pounding forces obtained from the analyses are used to investigate the pounding response between buildings RC buildings with equal heights and different dynamic characteristics considering Seismic Zone 1 of Turkey. The results presented in this study represents that gap values defined in TEC–2007 are insufficient

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