A comparison of seismic low cycle fatigue and extremely low cycle fatigue on steel moment frames with reduced beam section connection (RBS). (February 2019)

• Record Type: Journal Article
• Authors: Ghaderi, Mohsen; Gerami, Mohsen; Vahdani, Reza
• Is Part Of: International journal of fatigue. Volume 119(2019)
• Page Start: 139
• Page End: 149
• Publication Date: 2019-02
• Subjects: Low cycle fatigue -- Extremely low cycle fatigue -- Steel moment frame -- Reduced beam section connection (RBS) -- Cyclic void growth model; Materials -- Fatigue -- Periodicals; Materials -- Fatigue; Periodicals; 620.1122
• DOI: 10.1016/j.ijfatigue.2018.09.010
• Languages: English
• ISSNs: 0142-1123

Abstract

Highlights: Study the effects of LCF and ELCF on a reduced beam section connection (RBS). Low cycle fatigue is effective when the behavior of the structure's material is linear. The ELCF index is significant when the connection's material stresses exceeded the yield stress. Comparison of the damage induced in the LCF and the failure indices in the ELCF. Abstract: Damage to the connections of buildings with steel moment frames during past earthquakes indicates that the damage to some buildings cannot be justified by the mechanisms of common failure. This is due to the effects of low cycle fatigue (LCF) and extremely low cycle fatigue (ELCF) on the moment frame connections. On the other hand, studies on moment connections have mostly focused on the permitted connection capacity, and the issue of fatigue (LCF and ELCF) has not been considered in these types of connections. The present study focused on the effects of LCF and ELCF on a prequalified reduced beam section connection (RBS) in the steel moment frames of a 6-floor commercial complex and compared these two effects. The results showed that although the RBS connections of the studied structure were not damaged by LCF and ELCF, low cycle fatigue was effective when the behavior of the structure's material was linear. The extremely low cycle fatigue index was significant when the connection's material stresses, caused by an earthquake, exceeded the yield stress. In addition, the comparison of the damage ratios induced in the LCF method and the failure indices in the ELCF method on different floors indicated that the ratios of these two indices were consistent across all the floors.