Question

A bracket carrying a load of $125\text{kN}$ is connected to the column flange by means of two horizontal fillet welds, each of $180\text{mm}$ effective length and 10 mm thick. The load acts at $75\text{mm}$ from the face of the column as shown in figure. The throat stress developed is _______.

Answer 1

Throat thickness
$t=0.7\times 10=7\text{mm}$

Direct stress
$f_a=\frac{P}{2Lt}=\frac{125\times 1000}{2\times 180\times 7}=49.6{\text{N/mm}}^2$

Moment
$M=125\times {10}^3\times 75=9.375\times {10}^6\text{N-mm}$

The resisting couple due to bending in the two welds
$=(180\times 7\times f_b)\times 120$
$\therefore (180\times 7\times f_b)\times 120=9.375\times {10}^6$

$\Rightarrow f_b=62{\text{N/mm}}^2$

$\therefore$ Resultant stress
$f_R=\sqrt{3f_a^2+f_b^2}=\sqrt{3\times {49.6}^2+{62}^2}=105.95{\text{N/mm}}^2$