Fatih Alemdar

• PhD
• Professor (Assistant) at Yıldız Technical University

Corrosion damage is a serious problem in steel structures. The cross-sectional loss in the structural members due to corrosion reduces the load-carrying capacity of the members and the stability of their structures. In this study, the main reasons for the collapse of three steel sports infrastructure facilities after moderate snowfall were investig...

The connections are used to transfer forces and moments due to applied loading. The capability of the connection in the resisting moment is used to classify the types of connections in steelwork particularly for cold-formed steel. Classification schemes based on the total moment-rotation behavior have been developed to aid in the design and analysi...

The structural design process has many vital roles in preventing the collapse of structures and should be conducted according to national obligatory standards. However; structural failures or even catastrophic collapses based on improper design, underestimated design loads, unexpected extreme loads, and improper erection are reported worldwide on l...

This paper describes the experimental performance of the bolted stiffened end-plate (BSEP) and bolted flange-plate (BFP) connections using European hot-rolled profiles and built-up profiles. Four connections are designed and constructed according to FEMA-350 and are performed under cyclic loading. The influence of using different member profiles (E...

Rib-to-rib (RR) butt welded connections are one of the most sensitive locations for encountering fatigue failure in orthotropic steel decks (OSDs), and numerous fatigue cracks arising from these areas have been identified in existing OSD bridges. Due to dynamic factors in their service life bridges with an orthotropic steel deck (OSD) are prone to...

Bu çalışmada takviyeli alın levhalı bulonlu kolon-kiriş birleşiminin çevrimsel yükleme altında deneysel çalışması sunulmaktadır. Bunun için biri hadde profilleri ile diğeri yapma profiller ile oluşturulmuş olan iki adet numune hazırlanmıştır. Çalışmada hadde veya yapma profiller ile hazırlanmış takviyeli alın levhalı bulonlu birleşimin çevrimsel yü...

The long span orthotropic bridge decks applied around the World are used with open or closed cross-sectional longitudinal ribs placed below the steel deck to increase the strength of the deck. Fatigue cracks are developed in the longitudinal ribs due to traffic loadings. In this study, two different longitudinal ribs having trapezoidal and triangul...

Fiber-reinforced polymer (FRP) overlays have been successfully used in the aerospace industry to repair fatigue damage in aluminum plates. With this success there is potential for use of similar FRP overlays to repair fatigue damage in aging steel bridge structures. This study investigated the effectiveness of repairing fatigue damage in steel plat...

This paper presents the results from computer simulations of 914 mm (36 in.) deep girder-cross frame subassemblies to study the effects of distortion-induced fatigue and to evaluate the effectiveness of a newly proposed cost-effective retrofit measure. The proposed retrofit measure consists of adding steel angles connecting the girder web and the t...

Physical simulations of 914 mm (36 in.) deep girder-cross frame subassemblies subjected to cyclic loading were carried out to study the effects of distortion-induced fatigue and to evaluate the effectiveness of a new retrofit measure. The new repair method consists of adding steel angles connecting the girder web to the cross frame transverse conne...

This study evaluates the performance of various methods to prevent and repair fatigue damage in welded connections, a recurring problem that affects a significant number of steel bridges. Experimental tests and analytical simulations were carried out to investigate the fatigue performance of coverplate specimens in which the welded connections were...

Carbon-fiber reinforced polymer (CFRP)-overlay elements were developed with the purpose of enhancing the fatigue perfor-mance of welded connections in steel bridge girders. Fatigue tests of seven specimens, including four CFRP-strengthened specimens and three control specimens, were performed to quantify the effect of the CFRP overlays on the fatig...

This study focuses on evaluating retrofit measures for steel bridges with distortion-induced fatigue damage. Simulations using finite element models (FEA) were performed to analyze the complex stress field that develops in the web-gap region of bridge girders affected by distortion-induced fatigue. Finite element models were calibrated with experim...

Experiments and computer simulations were carried out at the University of Kansas to investigate the use of composite materials for strengthening and repair of fatigue-vulnerable steel bridges. Prefabricated CFRP overlays were attached to welded coverplate specimens using a layer of epoxy resin. The specimens were then subjected to three-point bend...

A parametric investigation into the use of CFRP materials to extend the fatigue life of vulnerable connection details in steel bridge girders is described in this paper. CFRP overlay elements were attached to an AASHTO category E" detail and tested under cyclic loading. Several parameters were studied experimentally and analytically, including the...

This study investigates mainly two different topics related to the use of CFRP's for strengthening and repair of steel bridges: the use of CFRP's to prevent damage in fatigue vulnerable welded connections prior to fatigue-crack initiation, and the use of CFRP's to stall the propagation of fatigue cracks in welded connections and in steel plates sub...