Steel Buildings in Europe

Title A.6 Worked Example – Bolted connection of an angle brace in tension to a gusset plate 6 of 6 4 – 103 The procedure to determine the throat thickness of the double fillet welds is the same for the gusset plate/column web connection and for the gusset plate/base plate connection. The following calculations show the design of the weld between the gusset plate and the base plate. It is possible to provide full strength double fillet welds following simplified recommendations, see SN017 [4] . However, that approach is too conservative for this example. SN017 [4] The recommended procedure is to choose a weld throat and to verify whether it provides sufficient resistance: In this case, try 4 mm  a . Design resistance for the double weld, according to the simplified method: l F N w,Rd w,hor Rd, 2  f a F vw,d w,Rd  EN 1993-1-8 § 4.5.3.3 2 w M2 u vw,d 233,66 N/mm 0,85 1,25 430 3 3       f f  233,66 4 934,6 N/mm w,Rd    F  467 kN 2 934,6 250 10 3 Rd,w,hor       N It supports the horizontal component of the force acting in the bracing: 161 kN sin 40 250 sin 40 Ed hor Ed,     N N Therefore the horizontal weld is OK. The same approach can be used to design the vertical weld (the gusset plate is welded to the column web). 6.3. Summary The following table summarizes the resistance values for the critical modes of failure. The governing value for the joint (i.e. the minimum value) is shown in bold type. Table A.2 Summary of the resistance values in the bolted bracing connection Mode of failure Component resistance Bolts in shear N Rd,1 282 kN Bolts in bearing on the angle leg N Rd,2 471 kN Angle in tension N Rd,3 407 kN Some modes of failure have not been verified in this example, such as the gusset plate in bearing and in tension. These verifications are not necessary because the thickness of the gusset plate is greater than that of the angle, and therefore the angle cleat would fail before the plate.