The new Eurocode for early-age concrete crack control generally follows and builds on BS 8007 for liquid-retaining
and containment structures and the fundamental theory for early-age thermal cracking in concrete. In conjunction with
CIRIA Report C660 summarising recent research and experimental data evenmore effective and economical design
should be possible. Unfortunately however there can be serious conflict in one major respect where large and
unnecessary increases in reinforcement can be required for controlled cracking of edge-restrainedmembers. Thus efficient use of rebar and fibre reinforcement combinations to achieve well distributed fine cracks withminimumtotal reinforcement at the critical steel ratio could be seriously undermined for other types of concrete structures as well as water-retaining structures. The paper therefore examines themajor changes in the new code for early-age concrete crack control and compares these both with BS 8007 for convenience and with the fundamental theory for early-age cracking to resolve any conflicts or errors.
Barry P. Hughes, DEng, DSc, PhD, CEng, FIStructE, FICE
Emeritus Professor, University of Birmingham, UK