Steel Buildings in Europe

Part 11: Moment Connections 11 - 13 t p > t p Figure 3.2 End plate – compression zone 3.3 Stiffeners The various types of stiffener used in an eaves connection are shown in Figure 1.3. A compression stiffener is usually provided. Other stiffeners should be avoided if possible. Stiffeners to the end plate are never needed – a thicker end plate can be chosen to increase the resistance. Column flange stiffeners are used to increase the resistance of the connection. In preference to providing stiffeners, increased resistance can also be achieved by:  Providing more bolt rows  Extending the end plate above the top of the rafter, as shown in Figure 3.3  Increasing the depth of the haunch  Increasing the weight of the column section. 2 1 1 Extended column – may require skew cut 2 End plate stiffener – not preferred Figure 3.3 Extended end plate connection 3.4 Bolts Bolts in moment connections are generally M20 or M24, class 8.8 or 10.9. In some countries, class 8.8 is standard. Bolts should be fully threaded, which means that the same bolts may be used throughout a building. Bolts are generally set out at cross-centres (gauge) of 90 or 100 mm. The vertical pitch is generally 70 to 90 mm. In some countries, common practice is to have bolts regularly spaced over the complete depth of the connection. In other countries there may be a significant distance between the ‘tension’ bolts and the ‘shear’ bolts. EN 1991-1-8 does not preclude either detail. Maximum bolt spacings are given in the Standard to ensure components do not buckle