Research On The Performance Of Minor Axis Flush End-plate Connections

In this paper, experiment on minor axis flush end-plate connections and minor axis seatand web angles connections under monotonic load is conducted to discuss the capacity ofthose connections. Minor axis flush end-plate is selected to go on further relevant study. Byusing ABAQUS correct and reasonable FE model is built comparing with the tests results, andeffects of different parameters on behavior of joints are researched. Initial stiffness ofconnections is calculated basing on equivalent T-stub in tension and component method ofEC3. A simplified model of flush end plate is proposed, and the correlation between keyparameters is obtained by MATLAB, then a simple calculation formula of the initial stiffnessof minor axis flush end plate connections is obtained by the simplified model and thecomponent method. Through this paper, the following conclusions can be obtained.1) Minoraxis flush end-plate connections is a typical semi-rigid connections, however seat and webangles connections is a hinge connections.2) The failure mode of minor axis flush end-plateconnections under negative moment is that out-of-plane bending deformation occurs in theflush end plate, local plate buckling occurs in the lower flange of beam and bolts are stretchbent.3) Increase of thickness of flush end plate, bolt type and depth of beam can improve thebehavior of connections. However, the way to arrive at an economic and reasonable design fora semi-rigid connection is not to increase thickness of flush end plate and bolt type blindly. Abetter scheme is that the thickness of flush end plate should be slightly below the nominaldiameter of bolts in tension.4) A20%reduction of the pre-tensile force of bolts has littleeffect on the initial stiffness of connections.5) Anti-slip coefficient of friction surface iswithout influence upon the initial stiffness of connections.6) The equivalent T-stub in tensionof EC3can’t exactly simulate flush end plate.7) A simple calculation formula of the initialstiffness of minor axis flush end plate connections can be obtained by the simplified model offlush end plate and the component method, and this formula indicates that the influential orderof key parameters affecting the initial stiffness of minor axis flush end plate connections isthickness of flush end plate, depth of beam and bolts type.