7. Tension tables

7.1Tension members: Single angles

EN 1993‑1‑1

For angles in tension connected through one leg, BS EN 1993-1-1, 6.2.3(5) refers to BS EN 1993-1-8, 3.10.3. However the Eurocode does not cover the case of more than one bolt in the direction perpendicular to the applied load. Therefore the resistance has been calculated using expressions from BS 5950-1 for angles bolted and welded through one leg.  The resistance is independent of the number of bolts along the angle and their spacing. Tables only give values for the cross-sectional check; see AD351[17] for more information.


The value of the design resistance to tension Nt,Rd  has been calculated as follows:



Aeq is the equivalent tension area of the angle
fy is the yield strength
γM0 is the partial factor for resistance of cross sections (γM0 = 1.0, as given in the National Annex).

The equivalent tension area of the section Aeq is given by:

For bolted sections:     
For welded sections:   


Ae = ae1 + ae2 but Ae ≤ 1.2 (an1 + an2)
ae1 = Ke an1 but ae1 ≤ a1
ae2 = Ke an2 but ae2 ≤ a2
Ke = 1.2 for grade S275
  = 1.1 for grade S355
an1 = a1 - nbolts d0t
a1 = h x t  if the long leg is connected
  = b x t  if the short leg is connected
nbolts is the number of bolts across the angle
d0 is the diameter of the hole
an2 = a2
a2 = Aa1
A is the gross area of a single angle.

Note:    A block tearing check (BS EN 1993-1-8, 3.10.2) is also required for tension members. However, block tearing resistances have not been tabulated, as there are too many variables in the possible bolt arrangements.