Resistance to transverse force tables
9.1. I and H sections and channels
(a) The design shear resistance
The design shear resistance V c,Rd is given by:
Code ref
§6.2.6 (1), (2)
where:
| A v | is the shear area for rolled I sections A v = A − 2 b t f + ( t w + 2 r ) t f but not less than η h w t w, for channels A v = A − 2 b t f + ( t w + r ) t f for tapered flange channels, the value of t f quoted in the section property tables is used in this formula (see Section 3.1) |
| f y | is the yield strength |
| γ M0 | is the partial factor for resistance of cross sections ( γ M0 = 1.0 , see Section 5.1) |
(b) Design resistance to local buckling
The design resistance of an unstiffened web, F Rd, to local buckling under transverse forces is given by:
Code ref
EN 1993-1-5,
§6.2 (1)
where:
Code ref
Figure 6.1
| f y | is the yield strength | |
| t w | is the thickness of the web | |
| L eff | is the effective length for resistance to transverse force ( χ F l y ) | |
| χ F |  | |
| l y | is the effective loaded length | |
| γ M1 | is the partial factor for resistance of members ( γ M1 = 1.0 , see Section 5.1) | |
 F |  | |
| F cr |  | |
| k F |  | |
| h w | is the depth between flanges = h - 2t f | |
| s s | the length of stiff bearing (see Figure 6.2 of EN 1993-1-5) | |
| c | the distance from the end of the stiff bearing to the end of the section. | |
The effective loaded length l y has been calculated as the least value of the following three expressions:
| l y1 |  | Eq (6.10) |
| l y2 |  | Eq (6.11) |
| l y3 |  | Eq (6.12) |
where:
| l e |  | Eq (6.13) |
| m 1 |  | |
| m 2 |  | |
| m 2 |  | |
(Note that, at present, EN 1993-1-5, §6.5(3) erroneously refers to Equations 6.11, 6.12 and 6.13. This error is due to be corrected by CEN.)
Values of F Rd have been calculated for two values of c, where c is the distance from the end of the member to the adjacent edge of the stiff bearing length, as shown in Figure 6.1 of EN 1993-1-5.
Code ref
EN 1993-1-5,
§6.1(4)
| c | = 0 for stiff bearing positioned at the end of the section. |
| c | = c lim for stiff bearing positioned at a distance c lim from the end of the section. This position represents the minimum value of c at which the maximum resistance of the web for a given stiff bearing length, s s is attained. |
where:
| c lim | = max (c buckling ; c bearing ) |
| c buckling |  |
| c bearing |  |
For the case where the stiff bearing is positioned at an intermediate distance (i.e. c < c lim ) the resistance given for c = 0 is conservative.