11.6Connections

11.6.2.1

Actual stress in bolt in shear, $f_{\mathrm{sb}}$ should be less than or equal to permissible stress of the bolt, $f_{\mathrm{as} b}$ as given below:

The actual stress in bolt in shear, $f_{\mathrm{sb}}=V_{\mathrm{sb}} / A_{\mathrm{sb}}$

The permissible stress in bolt in shear, $f_{\mathrm{as} b}=0.60$ $V_{\mathrm{nsb}} / A_{\mathrm{sb}}$

where

• $V_{\mathrm{sb}}=$ actual shear force under working (service) load,
• $\begin{aligned} V_{\mathrm{nsb}} & =\text { nominal shear capacity of the bolt as given } \\ & \text { in } 10.3 .3 \text {, and }\end{aligned}$
• $A_{\mathrm{sb}}=$ nominal plain shank area of the bolt

11.6.2.2

Actual stress of bolt in bearing on any plate $f_{\mathrm{pb}}$ should be less than or equal to the permissible bearing stress of the bolt/plate, $f_{\mathrm{apb}}$ as given below:

Actual stress of bolt in bearing on any plate,

$f_{\mathrm{pb}}=V_{\mathrm{sb}} / A_{\mathrm{pb}}$

The permissible bearing stress of the bolt/plate,

$f_{\mathrm{apb}}=0.60 V_{\mathrm{n} \mathrm{pb}} / A_{\mathrm{pb}}$

where

$V_{\mathrm{npb}}=$ nominal bearing capacity of a bolt on any plate as given in 10.3.4, and

$A_{\mathrm{pb}}=$ nominal bearing area of the bolt on any plate.

11.6.2.3

Actual tensile stress of the bolt, $f_{\mathrm{tb}}$ should be less than or equal to permissible tensile stress of the bolt, $f_{\mathrm{atb}}$ as given below:

Actual tensile stress of the bolt, $f_{\mathrm{tb}}=T_{\mathrm{s}} / A_{\mathrm{sb}}$

The permissible tensile stress of the bolt,

$f_{\mathrm{atb}}=0.60 T_{\mathrm{nb}} / A_{\mathrm{sb}}$

where

• $T_{\mathrm{s}} \quad=$ tension in bolt under working (service) load
• $\begin{aligned} T_{\mathrm{nb}} & =\text { design tensile capacity of a bolt as given in } \\ & 10.3 .5 \text {, and }\end{aligned}$

$A_{\mathrm{sb}}=$ nominal plain shank area of the bolt

11.6.2.4

Actual compressive or tensile or shear stress of a weld, $f_{\mathrm{w}}$ should be less than or equal to permissible stress of the weld, $f_{\mathrm{aw}}$ as given below:

The permissible stress of the weld, $f_{\mathrm{aw}}=0.6 f_{\mathrm{wn}}$

where

$\begin{aligned} f_{\mathrm{wn}} & =\text { nominal shear capacity of the weld as } \\ & \text { calculated in } 10.5 .7 .1 .1\end{aligned}$

11.6.2.5

If the bolt is subjected to combined shear and

tension, the actual shear and axial stresses calculated in accordance with 11.6.2.1 and 11.6.2.3 do not exceed the respective permissible stresses $f_{\mathrm{as}}$ and $f_{\mathrm{at}}$ then the expression given below should satisfy:

$\left[\frac{f_{\mathrm{sb}}}{f_{\mathrm{asb}}}\right]^{2}+\left[\frac{f_{\mathrm{tb}}}{f_{\mathrm{atb}}}\right]^{2} \leq 1.0$

where

$\begin{aligned} f_{\mathrm{sb}}, f_{\mathrm{tb}} & =\text { actual shear and tensile stresses } \\ & \text { respectively, and }\end{aligned}$

$f_{\mathrm{as} b}, f_{\mathrm{atb}}=$ permissible shear and tensile stresses respectively.

11.6.3.1

Actual stresses in the throat area of fillet welds shall be less than or equal to permissible stresses, $f_{a w}$ as given below:

$f_{\mathrm{aw}}=0.4 f_{\mathrm{f}}$

11.6.3.2

Actual stresses in the butt welds shall be less than the permissible stress as governed by the parent metal welded together.