Comparative study on seismic performance of precast and reinforced concrete wide beam-column connections

초록

The precast concrete (PC) moment-resisting frames with PC wide beams have been increasingly adopted in the construction of large-scale logistics centers and industrial factories. But the shear lag effect of wide beams can greatly affect the seismic performance of wide beam-column connections. Compared to monolithically-cast reinforced concrete (RC) wide beam-column connections, the PC wide beam-column connections have somewhat different seismic-resistant mechanism due to its inherent discrete connection details. Revealing the difference of shear lag mechanism in PC and RC wide beam-column connections can be beneficial to understanding their seismic resistance mechanisms and promoting the performance-based seismic design (PBSD) of PC moment-resisting frames constructed with PC wide beams. To this end, a pair of full-scale PC and RC wide beam-column connection specimens were fabricated and tested under reversed cyclic loads. The reinforcement strain responses along the wide beams of the PC and RC wide beam-column connections were also measured and compared to identify the shear lag effect. Furthermore, a series of numerical analyses was conducted to further investigate the shear lag mechanism behind overall seismic-resistant responses in PC and RC wide beam-column connections. It was found that the shear lag effect of wide beams had significant impact on the overstrength of wide beam-column connections, where the PC wide beam-column connection had higher overstrength capacity than RC wide beam-column connection because PC corbel can mitigate the shear lag effect of PC wide beams.

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