冷成型钢龙骨-石膏板自攻螺钉连接低周往复荷载试验-《建筑科学与工程学报》

文章信息/Info

Title:: Low Cyclic Load Experiment of Cold-formed Steel Self Tapping Screw Connection of Keel-plasterboard

Author(s):: CHEN Wei, CHEN Li-wei, CHEN Sheng-gen, ZHANG Yi-dong, SU Yi-ran, LIU Bin; Key Laboratory of Building Fire Protection Engineering and Technology of MPS, Tianjin Fire Research Institute of MPS

Keywords:: cold-formed steel; plasterboard; self tapping screw connection; shear performance; low cyclic load

摘要:: 开展了冷成型钢龙骨-石膏板自攻螺钉连接抗剪试验研究，完成了32个典型试件低周往复荷载试验，分析了螺钉边距和覆板层数对自攻螺钉连接抗剪强度的影响，并提出了抗剪强度简化公式。结果表明：由于石膏板沿板边与板内方向所具备的抗挤压能力不同，试件正向加载抗剪强度普遍小于负向加载抗剪强度；部分试件在达到抗剪强度峰值后荷载位移曲线发生突变，此时一般伴随石膏板迅速开裂或者螺钉拔出等现象；试件主要呈现石膏板挤压破坏，部分自攻螺钉存在少量倾斜现象；螺钉边距为10~25 mm时，试件抗剪强度随边距增大呈增大趋势；螺钉边距超过25 mm时，试件抗剪强度增长不明显；双层覆板试件抗剪强度明显高于单层覆板试件，但尚未达到单层覆板试件抗剪强度的2倍；所提出的抗剪强度简化公式预测结果与试验结果吻合良好。

Abstract:: The experimental research on the cold-formed steel self tapping screw connection of keel-plasterboard was carried out. The low cyclic load experiments of 32 typical specimens were completed. The influences of screw margin and number of surface plates on the shear strength of self tapping screw connections were analyzed, and the simplified formula of shear strength was put forward. The results show that because of the different anti extrusion abilities of plasterboard along the edge of plate and the inside direction of plate, the shear strength of specimen under positive load is generally less than that under negative load. The load-displacement curves of some specimens are abrupt after reaching the peak value of shear strength, which is generally accompanied by rapid cracking of plasterboard or bolt pull-out. The specimen mainly presents the extrusion damage of the plasterboard, and some self tapping screws have a small amount of tilts. When the screw margin is 10-25 mm, the shear strength of specimens increases with the increase of margin. When the screw margin exceeds 25 mm, the shear strength of specimens dont increase obviously. The shear strength of double surface plates specimen is significantly higher than that of single surface plate specimen, but has not reached 2 times of that of the single surface plate specimen. The predicted results by simplified formula of shear strength are in good agreement with the test results.