冷弯型钢剪切耗能框架-K形支撑结构抗震性能研究

STUDY ON THE SEISMIC PERFORMANCE OF COLD-FORMED STEEL FRAME WITH SHEAR ENERGY DISSIPATION K-SHAPED BRACES

  • 摘要: 为提升冷弯型钢结构抗震性能,推动多层冷弯型钢结构的发展,该文提出了冷弯型钢剪切耗能框架-K形支撑结构体系。共设计2个足尺单层单跨框架试件进行拟静力试验研究,通过变化耗能板宽厚比,得到试件的抗震性能指标并进行评估。同时,为了考察蒙皮效应的影响,在ABAQUS中对上述2个试件双面覆12 mm厚石膏板并对其滞回性能进行研究。此外,还建立多层冷弯型钢剪切耗能框架-K形支撑结构体系模型并对其进行弹塑性动力时程分析。试验及有限元分析结果表明:该结构滞回曲线饱满,在层间位移角达到2%以前,损伤主要集中在耗能板上,并依靠耗能板的滞回塑性变形耗能。双面覆石膏板之后,结构的极限承载力及抗侧刚度有所提高,但是不会影响结构的破坏模式。与冷弯型钢-钢板剪力墙结构相比,该文提出的新型结构在地震作用下各层层间位移角均明显减小,在8度罕遇地震作用下,结构横、纵向层间位移角减小幅度分别为43.29%和46.25%。

     

    Abstract: To improve the seismic behavior of cold-formed steel (CFS) structures and promote the development of multi-storey CFS structures, a CFS frame with shear energy dissipation k-shaped braces was proposed in this paper. The quasi-static tests of two full-scale one-storey one-bay specimens were carried out. By changing the width-to-thickness ratios of energy dissipation panels, the seismic performance indexes of the specimens were obtained and evaluated. In addition, to investigate the influence of diaphragm effect, the above two specimens were covered with 12 mm-thick gypsum boards on both sides in ABAQUS, and the seismic performance of the structures were studied. Furthermore, the models for multi-storey CFS frames with shear energy dissipation k-shaped braces were established and the elastoplastic dynamic time history analysis was carried out. The test and finite element analysis results showed that the structures proposed had plump hysteretic curves. Before the 2% inter-storey drift, the damage was mainly concentrated on the energy dissipation plates, and energy was dissipated by the plates too. The ultimate load carrying capacities and lateral stiffness of the structures were increased after the double-sided cladding of the gypsum boards, but it did not affect the failure modes of the structures. Compared with the CFS plate shear wall structure, the inter-storey drift of the structure proposed was significantly reduced under earthquakes, and the reductions of the horizontal and longitudinal inter-storey drift were 43.29% and 46.25% respectively under an 8 degree rare earthquake.

     

/

返回文章
返回