Steel braced frame systems (SBFs) having high stiffness and high strength are commonly utilized due to their resistance to lateral seismic forces in regions with high seismicity. In this study, concentrically braced frames (CBFs) having different bracing configurations are used to obtain the significance of the pulse period associated with near-fault (NF) ground motion by time-history dynamic analysis. Besides, far-fault (FF) ground motions are also used to compare with NF ground motion results according to chancing bracing configurations. To achieve dynamic responses of steel frames with different concentric bracings under NF ground motions, which especially have small, medium, and long pulse periods, 3-story and 4-span CBFs having different bracing configurations were selected as an example. 4 FF and 12 NF ground motions having different pulse durations were chosen to evaluate the dynamic response of concentrically braced frames. The results showed that peak ground acceleration (PGA) could be identified as a key parameter that controls the response of braced frames under FF ground motions. In addition, the ratio of the pulse duration to the first mode period is the dominant parameter when this ratio is only greater than 1.0 under the NF ground motions.

Bu çalışmada, Yalova ilinde inşa edilmiş olduğu varsayılan binaların deprem performansları, TBDY-2018 ve DBYBHY-2007 tasarım yönetmeliklerine göre değerlendirilmiştir. Çalışma kapsamında, binaların döşeme sistemi, kat sayısı ve yerel zemin sınıfları değiştirilerek, yapıların davranışları ve depreme karşı performansları STA4CAD betonarme yapısal analiz paket programı ile değerlendirilmiştir. Bu analizler sonucunda, elde edilen veriler ışığında yapıların doğal titreşim periyotları, taban kesme kuvvetleri ve etkin göreli kat ötelemeleri gibi parametreleri karşılaştırılmış ve beton ve donatı miktarlarındaki değişim incelenmiştir. Ortak bir mimari plan kullanılarak, yapıların tasarımında zemin sınıfı, kat sayısı ve döşeme sistemlerindeki değişiklikler göz önünde bulundurulmuş ve TBDY-2018 ve DBYBHY-2007’deki sınırlar dikkate alınarak yapıların davranışları incelenmiştir. Yapılan analizler sonucunda TBDY-2018’de zorunlu hale getirilen etkin kesit rijitliklerinin, yapıların davranışını önemli ölçüde değiştirdiğini ortaya koymuştur. Bu değişiklikler, yapıların daha rijit hale gelmesine ve dolayısıyla depreme karşı daha güvenli olmasına yol açmıştır. Bu doğrultuda, TBDY-2018’e göre tasarımı yapılan yapıların, DBYBHY-2007’ye göre çok daha fazla donatı ve betona ihtiyaç duyduğu görülmüştür. Ayrıca, DBYBHY-2007’ye göre tasarlanmış binaların deprem performanslarının, TBDY-2018’in belirlediği performans kriterlerini karşılamadığı tespit edilmiştir.

It is well known that structural displacement or ductility demands of structures subjected to near-fault ground motions are generally greater than ordinary ground motions. Therefore, the effect of earthquake records in the near region on the seismic behavior of structures has been widely studied in the last decades. Peak ground acceleration (PGA) is an important key parameter, which determines structural behavior. However, structural behavior depends on the distance of the structure to the fault zone, the ratio of peak ground velocity (PGV) to peak ground acceleration, the velocity pulse duration of ground motion, and the natural period of the structure. In this study, the seismic behavior of buildings with flat slab systems was investigated under near-fault ground motions. Linear time history analysis was performed for a 30-storey building designed according to TBEC-2018 using SAP 2000 finite element analysis software. Results were compared with the behavior of the building with a solid slab system. It is concluded that the ratio of PGV/PGA is very effective on the flat slab systems.

This study investigates the combined influence of forward directivity (FD), site class, and damping ratio on the seismic input energy demand of linear single-degree-of-freedom (SDOF) systems using an energy-balance framework. Four near-fault ground-motion sets with FD and non-forward directivity (NFD) were compiled for ZC and ZD soil classes, and elastic input energy spectra were computed for damping ratios of 2%, 5%, and 20%. Analysis of the earthquake records showed that increasing the damping ratio from 2% to 20% reduced the peak average input energy by approximately 35-40% for the selected records. The effect of forward directivity in the selected ground motion is that the average input energy increases by approximately 35-50% in the ZC soil class, while this increase is almost three times greater in the ZD soil class. Overall, increasing damping systematically reduces peak mean input energy, while FD effects markedly amplify energy demand, especially on soft soils. These findings underline that near-fault pulse-like characteristics and site conditions should be jointly considered when interpreting energy-based seismic demand.