Incrseased characteristic strength of confined lightweight aggregate concrete: the coefficient k
Eurocode 2 part 1-1: Design of concrete structures 11.3.7 (1)
If more precise data are not available, the stress-strain relation shown in Figure 3.6 may be used, with increased characteristic strength according to:
| flck,c = flck (1,0 + k σ2 / flk) | (11.3.24) |
where:
- flck,c
- the increased characteristic strength
- flck
- the characteristic strength of lightweight concrete, see Table 11.3.1
- σ2
- (= σ3) the effective lateral compressive stress at the ULS due to confinement
- k
- the coefficient depending on National Annex.
Recommendation
The recommended value of k is:
- 1,1 for lightweight aggregate concrete with sand as the fine aggregate
- 1,0 for lightweight (both fine and coarse aggregate) concrete.
