Design shear stress is less than the design shear strength; therefore OK

ei = 4 ■ d ei = 48 mm 62 mm provided, OK max(7 ■ d, 80 mm) = 84 mm 87 mm provided, OK

Example 12.8.2 Each end of a timber beam is connected to plywood gusset plates, which are glued to a rigid supporting structure in an office area. The beam is strength class C27 to BS EN 338:2003, spans 3.5m and supports a design load of 10.0kN/m at the ultimate limit states (ULS) and 6.83 kN/m at the serviceability limit states (SLS) from a combination of permanent and medium-term actions. It is bolted to the plywood-gusset plates at each end as shown in Figure E12.8.2. The connection comprises two 24-mm-thick Finnish birch plywoodgusset plates connected to the timber beam by 12-mm bolts acting in double shear. The bolts have a characteristic tensile strength of 400 N/mm2 and the connection functions under service class 2 conditions. The factor is 0.3 and the strength of the plywood gusset plates will comply with the requirements of EC5.

Compare the semi-rigid behaviour of the connection with the assumed fully rigid behaviour at the ULS and check the adequacy of the connection on the basis of semi-rigid behaviour. Also check the instantaneous deflection of the beam at mid-span for each condition.

Inner member:

75 X 300 mm C27 timber

0 0

Post a comment