the bolts are 20mm $\phi$ m and 4.6 grade

Step I

list bolt value=$\frac{fub\times Anb\times hn}{\sqrt{3}ymb}$

=$\frac{400\times245\times 1}{\sqrt{3}\times 1.25}$

Vdsb=45.26kN

Step II

dirct shera force per bolt=$\frac{w}{6}$ in horizontal direction

direct shear force per bolt=$\frac{2}{6}$in vertical direction

F1=$\sqrt{(\frac{w}{6})^{2}+(\frac{w}{6})^{2}}$=0.236w

Step III

force in bolt due to tortion

F2=$\frac{\sum(w.e)\gamma n}{\sum \gamma ^{2}}$ …