Within several Norwegian research projects, extensive field testing of high performance concrete structures has been carried out, and calculation methods and materials models for the hardening phase and the serviceability limit states in general have been verified. Within a recent Brite-Euram project, IPACS, a field instrumentation programme related to the hardening period and assessment of early age cracking has been carried out. Temperatures and strains have been measured in more than 70 points in several sections of a large culvert structure. In the instrumented sections the temperature history, and the corresponding stresses and strains were calculated by Diana. The second part of this paper considers the longtime behaviour of three concrete cantilever bridges with main span width ranging from 220 to 301 metre. Regarding the oldest bridge, built in 1987, deflections and strains have been recorded for a time period of 13 years. The bridges have been analysed by Diana utilising the phased analysis method, where the construction history is sub-divided into phases representing the real construction history as closely as possible.