Yazar "Soydan, Cihan" seçeneğine göre listele

Listeleniyor 1 - 4 / 4
  • Küçük Resim Yok
    Öğe
    A moment resistant beam end connection using energy dissipative couplers for precast concrete structures
    (Springer, 2025) Soydan, Cihan; Ozkaynak, Hasan; Surmeli, Melih; Senol, Erkan; Saruhan, Hakan; Yuksel, Ercan
    There is an increasing demand for precast reinforced concrete (RC) structures due to their undeniable advantages, such as rapid assembly, material standardization, and labor quality. The structural performance of precast RC structures depends not only on the quality of the precast members but also on joints and connections. In recent years, significant attention has been given to replaceable energy-dissipative devices for beam-to-column connections in precast RC structures. This paper proposes a novel moment-resisting energy-dissipative beam end connection in precast RC systems. The proposal is based on the results of intensive experimental and numerical studies conducted in the research project. The beam longitudinal reinforcements are connected to the joint using the developed fuse-type mechanical couplers (FTMCs) that have energy dissipation capability. While the bending moment in the connection is transformed into an axial force couple and transferred by FTMCs, the shear force is transmitted through the steel hinge at the center of the beam. The cyclic behavior of the proposed connection was experimentally investigated, resulting in a robust numerical model for the connection. The experiments demonstrated that the proper configuration of FTMCs in the connection enables reaching a 4% drift ratio without causing major damage to the RC beams. Macro models adopting pivot and kinematic hysteresis approaches for FTMCs were built in the numerical part. The pivot model reasonably and consistently predicted the experimental force-displacement relations of the proposed connections. The ability of the pivot model to estimate the energy dissipation capacities varies almost 6 similar to 16%.
  • Küçük Resim
    Öğe
    Betonarme Manto Uygulamasının Prefabrike Yapıların Deprem Performansına Etkisi
    (Süleyman Demirel Üniversitesi, 2019) Soydan, Cihan; Özkaynak, Hasan
    Ülkemizdeki sanayi yapıların çoğunluğunu, kolon-kiriş birleşim bölgelerinde moment aktarımı olmayan tek katlı prefabrike sistemleri oluşturmaktadır. Yaşanmış depremler sonrasında yapılan gözlemler; prefabrike yapıların deprem etkisi altında yüksek yatay yerdeğiştirmeleri nedeniyle kolon-kiriş birleşim bölgelerinde ve yapı genelinde önemli hasarların oluştuğunu göstermiştir. Bu tip yapı sistemlerinin depreme karşı güçlendirilmesi, sadece yüksek maliyetli cihazlar için değil öncelikli olarak insan yaşamı açısından hayati önem taşımaktadır. Bu çalışmada betonarme (BA) mantolama yönteminin prefabrike yapıların deprem performansındaki rolü sayısal olarak incelenmiştir. Çalışmanın ilk bölümünde, literatürde deneysel sonuçları yer alan BA mantolu ve mantosuz kolonların nümerik modelleri oluşturulmuştur. Tersinir tekrarlı yerdeğiştirme protokolü etkisi altında yapılan deneylerden elde edilen yükyerdeğiştirme ilişkileri, oluşturulan nümerik model sonuçları ile karşılaştırılmıştır. Nümerik modeller, belirli yerdeğiştirme eşikleri arasında deneysel sonuçları iyi bir şekilde tahmin edilebilmektedir. Deneysel olarak kalibre edilmiş olan nümerik model, üç boyutlu sanayi tipi mevcut bir yapı sisteminin lineer olmayan dinamik analizlerinde kullanılmıştır. Sayısal sonuçlar, mantolama sayesinde prefabrike yapının ortalama en büyük ve en küçük göreli ötelemelerin %54 ile %72 arasında değişen oranlarda azaldığını göstermiştir. Mevcut yapının seçilen kolonları, birim şekildeğiştirme açısından değerlendirildiğinde; güvenlik sınırı (GV) civarında olan kesit performansının BA mantolama ile minimum hasar sınırının (MN) altına çekildiği görülmüştür.
  • Küçük Resim
    Öğe
    Experimental İnvestigation And Pseudoelastic Truss Model For İn-Plane Behavior Of Corrugated Sandwich Panels With Polyurethane Foam Core
    (Elsevier, 2021) Özkaynak, Hasan; Yüksel, Ercan; Güllü, Ahmet; Soydan, Cihan; Khajehdehi, Arastoo; Şenol, Erkan; Saghayesh, Amir Mahdi; Saruhan, Hakan
    Sandwich panels are commonly used in facades and the roofs of industrial buildings due to their well-known advantages. However, there is limited data about the in-plane behavior of the panels. Hence, this paper aimed to propose a pseudoelastic truss model to represent the effective in-plane stiffness and strength properties of the corrugated sandwich panels with a polyurethane foam core. Two separate sets of experiments (mock-up and system test) were conducted in the laboratory. The variables were the number of fasteners, sheet thickness, loading direction, and number of ribs. The number of fasteners, sheet thickness, and loading direction are the most effective parameters for the in-plane behavior. A formula was proposed to compute axial stiffness of the truss members by considering the effective parameters. Experimental results showed that the proposed robust truss model could give a good estimate of the pseudoelastic stiffness and maximum load bearing capacity of the sandwich panels.
  • Küçük Resim Yok
    Öğe
    Monotonic Behavior of a Novel Energy Dissipative Mechanical Connector
    (Springer Science and Business Media Deutschland GmbH, 2024) Özkaynak, Hasan; Şenol, Erkan; Yüksel, Ercan; Soydan, Cihan; Sürmeli, Melih; Karakuş, Kubilay; Saruhan, Hakan
    Prefabrication technology has gained an increasing demand during the past decades due to some crucial benefits such as; ensuring material and labor quality and quick assembling features. Past earthquakes have shown that beam to column connections of precast structures demonstrated inadequate seismic performance. Lack of robust connections, inadequate detailing of ductile elements and displacement incompatibility of structural and non-structural elements led to non-uniform distribution of lateral loads among the structural system. Thus, special attention should be paid to the design and construction of beam to column joints. Several proposals exist for the joints in the Turkish Building Earthquake Code-2018 (TBEC-2018), which are categorized as moment resisting and non-moment resisting connection details. However, all these proposed connection details need concrete pouring and steel welding on-site requiring careful inspection during construction. In this study, fuse type mechanical couplers (MCs) are proposed, as a robust dry connection tool for use in beam to column connections of precast structures. The main philosophy of the connection aims to decouple the moment effects to two axial forces in opposite directions acting on MCs, where the shear force is transferred by a steel hinge, which is located at the natural axis of the beam. Since the fuse elements are strut type slender elements, they have serious vulnerability in terms of buckling. The preliminary development process for the MCs with improved buckling behavior is demonstrated herein. Preliminary monotonic experiments performed on MCs showed that the preliminary design could contribute to energy dissipation by yielding of fuse elements. The buckling behavior could be improved by the use of external steel jackets. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2024.