Seismic vulnerability of prefabricated reinforced concrete frame structure based on local outsource steel tube bolted column–column connection

Abstract

In this paper, the seismic performance of a prefabricated frame structure with a local outsource steel tube bolted column–column connect is evaluated from the perspective of seismic vulnerability theory. Firstly, a simplified model of the prefabricated frame structure was constructed and validated by experiments. Then, a six-story prefabricated reinforced concrete frame structure (PRCS) and a cast-in-situ reinforced concrete frame structure (CRCS) were designed as examples to get the increment dynamic analysis (IDA) of the structure under 12 ground motions, and the two-parameter damage model was used as the structural requirement index. As a traditional structural requirement index-the maximum inter-storey drift angle cannot accurately describe the mechanism of structural damage. Therefore, two types of damage models are compared and analyzed. In addition, in order to evaluate the damage of frame structure effectively, a new damage index weighted combination method is proposed, and its feasibility is verified. Finally, the IDA curve and vulnerability curve with Kunnath two-parameter damage model and the maximum inter-story displacement angle as the requirement index are drawn. The results show that the two-parameter damage model is more accurate than the maximum inter-storey drift angle model in evaluating the seismic performance of the PRCS and CRCS. It shows that the maximum inter-story displacement angle model can overestimate the collapse resistance of the PRCS by 60.7% on average, and the collapse resistance of the CRCS by 75.67% on average. The seismic performance of the CRCS is better than that of the PRCS as the seismic intensity increases. Although the seismic performance of fabricated columns is similar to that of cast-in-place columns, there is still a certain gap in the seismic performance of frame structures.

An experimental study of the shear behavior of joints in precast concrete columns

“…But on-site assembly brings a large number of joints into play in precast concrete structures, and joints are generally considered as weak points in concrete structures (Ding et al, 2021;Tsoukantas and Tassios, 1989). Because columns are usually the main load-bearing components of a structure, the shear performance of the joints joining precast columns has a major impact on the safety of the entire structure, especially under earthquake loading (Belleri et al, 2015;Zhang et al, 2021). Wu and Wei (2021) have recently proposed the new type of column-to-column connection shown in Figure 1.…”