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Increasing demand for high speed railway lines necessitates reducing construction and maintenance costs. Accordingly, RC slab tracks are preferred due to their advantages such as being almo...

The effectiveness of 100/30, 100/40 and SRSS directional combination rules on the response of asymmetric setback buildings is examined. Because of the irregularity in setback buildings, the maximum seismic response would be correlative with the direction of earthquake. To verify the directional combination rules of mode superposition methods, the time history analyses of setback buildings to real earthquake records are carried out. Example analyses have been used to compare the validty and accuracy of SRSS and percentage methods for frame and dual frame-wall systems.

Precast hollow-core slabs (PHSs) are widely used in precast construction due to their relatively low dead weight and easy assemblage. Cast-in-place topping concrete (TC) is utilized to obtain composite sections and to enhance in-plane stiffness of the slab system. Shear transfer between the layers of a composite slab can be provided by the upper face roughness of PHS. However, the roughening process may not be preferred in some plants. This paper evaluates the efficiency of Z-type shear connectors applied in the interface between PHS and TC. Three dissimilar interface conditions (i.e., Z-reinforced, smooth and rough) were studied experimentally in full-scale specimens. Push-off loading was applied to evaluate the interface shear transfer capability of the specimens, and Z-type shear connectors were found to be the most effective when they are applied at each joint between PHSs. The achievements of some code equations to assess interface shear strength were also investigated, and an alteration for the interface shear capacity equation of ACI 318M is proposed.

The goal of this paper is to investigate the non-linear response and to assess the seismic performance of a six story eccentrically braced steel frame (EBF). For this, split-K-braced EBF with high ductility level designed according to the Turkish Earthquake Code-2007 (TEC-07) is analyzed under seven selected earthquake records. The performance of the EBF is assessed considering drift, story and base shear demands, brace and column axial forces and bending moment demands, link beam shear force and rotation demands. Mean values of the demands are used in the performance assessment. The provisions based on capacity design approach specified in TEC-07 for EBFs with high ductility level are discussed by employing the findings., Bu çalışmada, Deprem Bölgelerinde Yapılacak Binalar Hakkında Yönetmelik-2007 (DBYBHY-2007) ye göre boyutlandırılan altı katlı dış merkez çaprazlı bir çelik perdenin deprem performansı, zaman tanım alanında doğrusal olmayan hesap yöntemi kullanılarak değerlendirilmiştir. Bu değerlendirmede göreli kat ötelemeleri, kat kesme kuvvetleri, çapraz ve kolonların iç kuvvet istemleri ile bağ kirişi kesme kuvveti ve dönme istemleri dikkate alınmıştır. Zaman tanım alanında doğrusal olmayan analizler yedi adet deprem ivme kaydı kullanılarak gerçekleştirilmiştir. Analizler sonucu elde edilen istemlerin ortalama değerleri esas alınarak dış merkez çaprazlı çelik perdelerin kullanıldığı orta yükseklikteki binalar için DBYBHY-2007'de öngörülen kapasite tasarımı yaklaşımının yeterliliği araştırılmıştır.

An attempt to estimate the displacement demands of precast cantilever columns has been presented here. The purpose of the findings presented is to set up a more reliable design philosophy based on dynamic displacement considerations instead of using acceleration spectrum based design which initiates the action with unclear important assumptions such as the initial stiffness, displacement ductility ratios etc. The sole aim of this chapter is to define a procedure for overcoming the difficulties rising right at the beginning of the traditional design procedure.

The purpose of this study is first to determine the conditions for excessive torsional irregularity and then to discuss the validity of code provisions. A parametric investigation is performed on six groups of typical struc- tures with varying shear wall positions, story, and axis numbers. It is found that torsional irregularity coefficients increase as the story numbers decrease, i.e., maximum irregularity coefficients occur for single-story structures. They reach maximum values when the asymmetrical shear walls are placed as close as possible to the centers of mass. However, the results obtained for floor rotations are quite contradictory. A new provisional definition for torsional irregularity coefficient based on floor rotations is proposed.