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K 2 = (ε 1 + ε 2)/(2ε 1) (7.13) where ε 1 is the greater and ε 2 is the lesser tensile strain at the boundaries of the section considered, assessed on the basis of a cracked section. Crack width calculations according to eurocode 2 Eurocode 2 (EN1992-1-1) proposes equations for the calculation of crack width, taking into account several parameters, like the concrete and steel strain and reinforcing bar diameters.
CRACK WIDTH CALCULATIONS ACCORDING TO EUROCODE 2 Eurocode 2 (EN1992-1-1) proposes equations for the calculation of crack width, taking into account several parameters, like the concrete and steel strain and reinforcing bar diameters. According to Eurocode 2, the crack width, w k, can be calculated from the following equation: wk = sr,max (εsm –εcm), where sr,max: the maximum crack spacing εsm: the mean strain in the reinforcement under the relevant combination of loads, including the effect of imposed deformations and taking into account the effects of tension stiffening. Fisica molecular e termodinamica pdf. Only the additional tensile strain beyond the state of zero strain of the concrete at the same level is considered εcm: the mean strain in the concrete between cracks • The difference εsm –εcm can be calculated from the following expression:, where: σs: the stress in the tension reinforcement assuming a cracked section. For pretensioned members, σs may be replaced by Δσp the stress variation in prestressing tendons from the state of zero strain of the concrete at the same level.
Αe: the ratio Es/Ecm ρp,eff (As + ξ1 2 Ap’)/Ac,eff,where Ap‘ is the area of pre or post-tensioned tendons within Ac,eff.