Moment redistribution without explicit check on the rotation capacity: the values of k1, k2, k3, k4 and k5
Eurocode 2 part 2: Design of concrete bridge structures 5.5 (104)
In continuous beams or slabs which:
a) are predominantly subject to flexure and
b) have the ratio of the lengths of adjacent spans in the range of 0,5 to 2,
redistribution of bending moments may be carried out without explicit check on the rotation capacity, provided that:
| δ ≥ k1 + k2 xu/d for fck ≤ 50 MPa | (5.10a) |
| δ ≥ k3 + k4 xu/d for fck > 50 MPa | (5.10b) |
| δ ≥ k5 where Class B and Class C reinforcement is used | |
| No redistribution is allowed for Class A steel |
Recommendation
In these expressions for redistribution of bending moments the recommended value for k1 is 0,44, for k2 is 1,25(0,6 + 0,0014/εcu2), for k3 is 0,54, for k4 is 1,25(0,6 + 0,0014/εcu2), and for k5 is 0,85. Where εcu2 is the ultimate strain according to Table 3.1.
