单斜无黏结内藏钢板支撑剪力墙滞回性能的试验研究

Experimental study on the hysteretic behavior of single-diagonal unbonded steel plate brace encased in reinforced concrete panel

通过6个单斜无黏结内藏钢板支撑剪力墙试件的拟静力试验,研究无黏结材料及支撑与墙板间的间隙、墙板内的加强构造措施与钢筋布置、墙板的厚度和混凝土强度等因素对试件滞回性能的影响。试验表明,在破坏前,所有试件均无强度和刚度退化现象,其骨架曲线呈双折线形式,试件破坏时的侧移角分别达1/87～1/29。当墙板与钢板间的间隙较小且均匀、墙板内钢筋布置合理时,试件的耗能能力和延性较好;墙板在局部间隙较大的部位易较早被支撑冲切或弯曲破坏。试验后钢板支撑均保留残余的多波弯曲变形,说明支撑并非不失稳,而是以多波失稳的形式来提高其稳定的承载力,直至达到屈服承载力为止。

Six quasi-static tests on single-diagonal unbonded steel plate brace encased in reinforced concrete panel, referred to as panel buckling-restrained brace （panel BRB）, arc conducted. The effects of the unbonded materials as well as the clearance between the panel and the core brace, the configuration of the reinforcement and the steel bars, the thickness of the panel and the concrete strength on the hysteretic behavior of panel BRBs are investigated. The results show that all panel BRBs exhibit stable hysteretic behavior without deterioration in load resistance and stiffness before failure of the panels, and the skeleton curves of all the specimens are close to the bilinear models. The lateral drifts of the specimens at failure are as high as 1/87-1/29. The tests also indicate that the specimens with more even and smaller clearance and reasonable steel bar configurations performed better, whereas where the clearance is slightly larger, the specimens fail earlier by either punching shear or local flexure. The braces still retain residual flexural deformation with multiple waves after the test, which testifies to that the stability capacity of the core brace has been enhanced to its yield strength by the buckling form with multiple waves.