自攻螺钉波峰连接的抗剪性能试验研究

Shear tests of screw connections in crest-fixed profiled steel sheetings

为了满足防水要求,目前我国在蒙皮连接上广泛采用自攻螺钉在压型钢板的波峰处与构件相连的形式。通过对30个波峰连接的自攻螺钉连接件的试验研究,探索波峰连接的抗剪性能,同时比较支承构件(以下简称支承板)板厚不同对连接试件抗剪性能的影响。结果表明,支承板过薄时,对螺钉根部锚固力不足,会导致螺钉在受力过程中倾斜,使试件的抗剪承载力大大增加而刚度降低;支承板越薄,其性能对安装缺陷越敏感;当支承板达到一定厚度,其厚度的变化对试件抗剪承载力影响不大;压型钢板波高越高,试件的抗剪承载力越低;波峰连接的抗剪承载力和抗剪刚度远远低于相同条件下波谷连接的相应性能,连接的抗剪承载力的降低,将较大影响蒙皮体的整体抗剪性能,但与裸骨架相比,此种连接形式仍具有相当的受力蒙皮作用可资利用。

In China, profiled steel sheeting claddings are commonly crest-fixed to members with self-tapping screws in order to improve its waterproof performance. Thirty shear tests of screw connections in crest-fixed profiled steel sheeting were conducted. The shear behavior of these connections, including the shear-carrying capacity and the shear rigidity, has been evaluated, and the effect of the thickness of the supporting member board, ‘the supporting board＇ for short below, was also studied. The results show that, both the shear-carrying capacity and the shear rigidity of the connections in crest-fixed profiled steel sheeting are significantly lower than those in the valley-fixed. The shear-carrying capacity reduction influences the overall shear behavior of the diaphragm. But comparing with the bare skeleton, it has considerable stressed skin diaphragm action for benefit. When the supporting board is excessively thin, the bolt inclination, due to insufficient anchorage force around its root, results in great increase of the shear-carrying capacity and reduction of the shear rigidity. But when the supporting board reaches certain thickness, additional variation of thickness has almost no influence on the shear behavior of the connections. The thinner the supporting board, the higher the sensitivity to its fixing is. The larger the wave height, the lower the shear-carrying capacity is.