碳纤维布抗震加固开门窗洞口砌体墙片的试验研究与受剪承载力分析

Experimental investigations and analysis of shear capacity of masonry walls with window and door openings reinforced with CFRP sheets

通过对6片开门窗洞口砖砌体墙片在低周往复荷载作用下的抗震性能试验研究,探讨碳纤维布用于抗震加固无筋开洞口墙片的破坏形态、受力特性和加固效果,对比不同碳纤维布粘贴方式对无筋开洞口砌体墙片抗震加固效果的影响,据此建议对地震区开窗洞墙体采用沿洞口周围粘贴碳纤维布并在窗洞角部附加锚固碳纤维布条的有效加固方式,对开门洞墙体采用沿洞口周围粘贴碳纤维布并在宽墙肢上对角粘贴碳纤维布的有效加固方式。同时根据试验研究结果,建立以碳纤维布拉杆机制为基础的碳纤维布加固开洞口砌体墙片的受剪承载力计算模型,计算结果与试验结果吻合较好,说明该计算模型能较好地反映碳纤维布与无筋砌体墙体共同工作的受力机理,可供工程设计参考使用。

An investigation of the seismic behavior of masonry walls with window or door openings reinforced with Carbon Fiber Reinforced Polymer （CFRP） sheets is presented. Six specimens were tested by horizontal cyclic loading combined with constant gravity loads. The failure mode, mechanical properties of specimens, strengthening effects and comparison of different retrofitting schemes are explored. The experimental results indicate that the retrofitting techniques using CFRP sheets, proposed in this paper, am significantly effective for improving the seismic performance of unreinforced masonry walls with openings. In addition, shear capacity of the masonry walls with openings reinforced with CFRP is also analyzed. Based on the assumption of the mechanism of CFRP sheets acting as the tensile bars on wall surfaces, a validating calculation of shear strength is proved to be considerably in accordance with test results, which demonstrates a good working condition of CFRP sheets together with masonry walls.