COMPARISION OF INTERNATIONAL CODES FOR STEEL ANCHORS DETAILS USING IN SEISMIC STRENTHENING

Abstract

Having poor seismic performance reinforced concrete frame must be strengthened to reach sufficient seismic performance. The main factor that affects the seismic performance, designing and application of the anchor dowels in the connection zone of infill shear wall and weak reinforced frame. Connection between the frame and the infill wall are usually achieved by using dowels that are placed in the holes drilled into inner faces of the frame members, and fixed by a resin. In this study, the design and detailing guidelines for the design of the post-installed anchors in TEC (2007), ACI 318, JCI (2001) and IS15988 have been compared. According to the results, in ACI 318-14, the shear capacity of anchors is effected by embedment depth, anchor bar diameter, concrete strength, strength of the bar and edge distance. In TEC-2007, shear strength is affected only by two properties of the anchor bar: strength and diameter. JCI-2001 design code considers the two factors outlined in TEC-2007 and concrete strength. Based on the comparison conducted in this study, there are insufficient guidelines in TEC-2007 for the design and detailing of anchor bars that are typically used as connection between an existing frame and new RC infill wall.

Keywords

• Infill walls
• Post-installed anchors
• Strengthening
• Shear capacity

Sismik Güçlendirmede Kullanılan Ankraj Detayları İçin Uluslararası Yönetmeliklerin Karşılaştırılması

Öz

Deprem performansı yetersiz olan betonarme çerçevelerin yeterli performans seviyesine gelebilmesi için betonarme perde duvarlar ile güçlendirilmesi gerekmektedir. Sonradan yapılan betonarme perde duvarların davranışını etkileyen en önemli unsur çerçeve ve betonarme duvar arasında bağlantı olarak kullanılan ankrajların tasarımı ve uygulamasıdır. Çerçeve ve betonarme dolgu duvarlar arasındaki bağlantı genellikle çerçeve parçalarının iç yüzeylerine açılan deliklere yerleştirilen ankraj donatılarının reçine ile sabitlenmesiyle elde edilir. Bu çalışmada ankrajlar için TEC–2007, ACI 318–14, JCI–2001 ve IS1–5988 gibi yönetmeliklerde verilen tasarım kuralları karşılaştırılmıştır. Yapılan karşılaştırmaya göre ACI 318-14’te, ankrajların kesme dayanımının gömme derinliği, donatı çapı, beton dayanımı, ankraj donatı dayanımı ve kenar mesafesi ile ilişkili olduğu görülmüştür. TEC-2007’de ise ankrajların kesme dayanımı sadece ankraj donatısının çekme dayanımı ve ankraj çapından etkilendiğinden bahsedilmektedir. ISI–5988, JCI-2001’in TEC- 2007’ gibi beton basınç dayanımına dikkat ettiği görülmüştür. Bu çalışmada dört yönteminde kıyaslanması sonucunda, mevcut çerçeve ve yeni betonarme dolgu duvar arasında bağlantı olarak kullanılan ankrajlar için TEC-2007’nin yetersiz kaldığı görülmüştür.

Anahtar Kelimeler

• Perde duvar
• Ankraj
• Güçlendirme
• Kesme kapasitesi

Kaynakça

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