雙角鋼剪力連接件之實驗探討

Abstract

本研究提出以雙角鋼作為剪力連接件，並以實驗方法進行研究。依Eurocode 4相關規範製作七組試體並進行試驗，以探討角鋼間淨距與角鋼尺寸對力學行為之影響。試驗結果顯示，雙角鋼剪力連接件的破壞模式均為混凝土承壓破壞，角鋼僅明顯變形；抗剪強度等同於5至7顆剪力釘；除一組試體外，各組試體之韌性均滿足Eurocode 4之要求。參數影響方面，抗剪強度隨著角鋼間淨距的增加而增大；角鋼對承壓混凝土之圍束效應隨角鋼間淨距的增大而減弱，隨角鋼厚度的增加而增強。本研究基於壓拉桿理論建立雙角鋼剪力連接件之力學分析模型，並以迴歸分析擬合角鋼對於混凝土之圍束係數，進而提出抗剪強度計算公式。

This research aims to evaluate experimentally the strength and ductility of the Double Angle Shear Connectors. Seven specimens were fabricated and conducted push out test according to Eurocode 4. The variable parameters included angle dimension and the clear distance between two angles. The experimental results demonstrated the failure mode was the crush of the concrete while the angle deformed insignificantly. The shear strength of a pair of angles is equal to that of 5-7 shear studs. Except one specimen, all specimens met the ductility requirement of Eurocode 4. The results also showed that shear strength of the double angles increased with the increase of the angle clear distance. The angles can provide a confinement effect on the concrete and enhance the compressive strength. The confinement effect attenuated with increase of the clear distance and enhanced with increase of the angle thickness. Using the strut and tie model and regression analysis, an expression for calculating the shear strength of the double angle shear connector is proposed and the expression can predict well the test results.