Paper by STET RUITER from ISCR 8th 1998 Lisbon Portugal
The last decade, the technology to design concrete mortars with a high compressive strength have evolved tremendously. The strength of concrete has progressed upto strength values of 130 Mpa. The development of high strength concrete can give the traditional pavement construction techniques a new impulse. Due to the relatively short hardening period and the strength development, the construction period and necessary time for hardening can be reduced to 24-36 hours. The progressive strength-development with high internal stresses due to hardening, also implies a higher risk towards shrinkage cracking. This especially reflects to concrete mortars with a low w/c ratio and a high cement content, ergo high strength concrete. The risk of premature failure is examined with a special purpose FEM program. The risk early-age cracking e.g. feasability of high-strength concrete in road construction is evaluated based on the stress-strength development of fresh, hardening concrete.