本研究旨在探討使用自攻螺絲作為木構造接點緊固件的剪力行為，與自攻螺絲運用於集成非膠合構件的彎矩傳遞效益與力學行為。透過改變自攻螺絲鎖入角度試圖提升接點的力學性能，並在破壞前提供更佳的韌性。經由足尺剪力試驗與自攻螺絲拉拔試驗及其他附帶材料試驗，驗證本研究接點具備更佳的力學效益。試驗結果亦對照歐盟木構造設計規範雙剪強度與破壞模態評估公式(EuroCode5，Equation 8.7)並預測接點的破壞模態。
本研究剪力試驗中探討不同角度(0°、30°、45°)，與不同配置(單側鎖入、兩側鎖入)接點的力學行為與破壞模式。剪力試驗以萬能試驗機施加3mm/min向下載重，加載至試體強度明顯下降或外觀破壞。由試驗結果，相比於水平鎖入螺絲，傾斜鎖入的試體在接點剪力強度皆有提升。30°與45°傾斜鎖入試體極限強度分別提升8%與20% ; 降伏強度則分別提升19%與40%。在勁度方面，傾斜鎖入的提升效益更加明顯，30°與45°鎖入分別高出水平鎖入179%與217%。由此結果可見自攻螺絲傾斜鎖入對於接點剪力強度的提升具有相當效益。傾斜鎖入接點具備良好的延展性，和水平鎖入接點相比其延性比高出82%、且均在四倍以上，歸類為中等延展性破壞。
對照歐盟木構造設計規範剪力評估公式(EuroCode5 ， Equation 8.7)，其中水平鎖入試體與30°單側鎖入試體對應破壞模態為ModeIII，30°雙側鎖入與45°鎖入試體對應ModeI。代表水平與較小傾斜角度鎖入的接點由緊固件產生塑性鉸控制破壞，較大角度鎖入與雙側配置自攻螺絲下，緊固件相對強度與剛度較大因此由木材壓潰控制。且剪力試驗極限強度均約為理論強度的兩倍左右，代表此公式運用於評估國產材的木構造剪力接點具備相當足夠之安全邊際。考慮自攻螺絲與木材間綜效作用，與水平鎖入試體相比，30°鎖入試體的強度增加量有約50%來自拉拔力的貢獻，45°鎖入試體的強度增加量則完全來自於拉拔力貢獻。因貫入螺絲長度較長而能提供較大抗拉拔力，此抗拉拔力的增加將對接點剪力強度有很大的貢獻。
本研究將剪力試驗之接點配置運用於續接非膠合樓板，設計三種試體型式，分別為全連續(AC)、外部連續(OC)、內部連續(IC)，以千斤頂進行四點抗彎試驗，測試其力學性能。樓板構件以全連續為基準分析彎矩傳遞效益。外部連續型式極限強度理論上為全連續的67%，而經續接後為87%，增加30% (以87% / 67%計算)；內部連續型式極限強度理論上為全連續的33%，而經續接後為68%，增加106% (以68% / 33%計算)。可見此類以自攻螺絲集成與續接的非膠合樓板，具備相當程度的彎矩傳遞效益。
總結本研究，傾斜鎖入自攻螺絲運用於受剪力接點，具備良好的力學性能，除較高強度與剛度外，也具備較佳延展性。而自攻螺絲作為緊固件續接非膠合樓板亦表現出良好的彎矩傳遞能力。此類應用國產木材與結構用自攻螺絲的接點在本研究具備優良力學性能。未來若有更多相關研究提供設計者安全可靠的遵循依據，應用此類國產建材都將能符合低碳足跡、循環經濟與扶植在地產業永續發展等重要價值。

This thesis investigates the effects of self-tapping screw(STS) insertion angles and configurations on the shear behavior of timber joints composed of wood and steel. The specimens are made of Taiwan domestic Japanese cedar (Cryptomeria japonica) with a cross section of 6×6 cm and a height of 30 cm. A shear test specimen is made up of three laminas. The shear test explored the mechanical behavior and failure mode of joints with different angles (0°, 30°, 45°) and configurations (single、double-side insertion). Shear tests of joints and screws pull-out tests reveal that inclined screws significantly enhance joint performance compared to horizontal insertion. Specifically, screws inserted at 30° and 45° exhibit ultimate shear strengths increased by approximately 8% and 20%, respectively, and yield strengths increased by 19% and 40%. The joint stiffness improvement is even more pronounced, with 30° and 45° angles showing increases of 179% and 217% compared to horizontal screws. Load-displacement curves for inclined screws display a secondary strength increase after the initial peak, indicating improved ductility and energy dissipation capacity. Moreover, the contribution of pull-out resistance, especially at larger insertion angles, plays a critical role in the shear strength of the joints, a phenomenon known as the “rope effect”. This effect is not fully considered by existing European Union (EU) timber structure design code (EuroCode 5), which tend to underestimate strength for inclined screws. Comparing the shear test results with EuroCode5, the corresponding failure modes of the horizontal insertion and the 30° single-sided insertion specimens are Mode III, and the 30° double-sided insertion and 45° insertion specimens are Mode I. This means that the horizontal and small-angle insertion joints are controlled by the plastic hinge generated by the fasteners. The ultimate strength of the shear test is about twice the theoretical strength, which means that this formula has a sufficient safety margin. The study also demonstrates the potential of self-tapping screws to improve the moment-transition capability in AFLT slab. The two connection and lamination methods in this study, external continuity (OC) and internal continuity (IC), respectively increase the moment-transition capability by 30% and 106%. Summarize the above research results, this study provides instructive insights and data for optimizing steel-timber joints designs composed of self-tapping screws under varied angles and configurations. In conclusion, more relevant research is needed in the future to provide reliable design rules for such joints using domestically produced materials in Taiwan.

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