The objective of the present report is to evaluate the state of harmonised use of the Eurocodes in the EU and EFTA Member States. Besides that, the report is deemed to assess the potential for further harmonisation and the associated needs to support the on-going activities of CEN/TC250 "Structural Eurocodes" in the development of the second generation of the Eurocodes.
The report analyses the national choices of the 28 EU Member States and two EFTA Member States (Norway and Switzerland). The European Commission Nationally Determined Parameters Database (NDPs Database) was used as a source of information on the countries' choices regarding the values adopted in the Eurocodes National Annexes.
The data available was subject of extensive analyses, comprising (i) assessment of the representativeness of the data set to draw conclusions on the country choices, (ii) examination of harmonised patterns of the NDPs, per country, Eurocode and for specific Eurocodes parts, (iii) study of cross-border convergence of the maps for climatic and seismic actions, (iv) identification of specific NDPs that achieved a high or a low consensus in the national choices, and (v) analysis of parameters with the largest divergence from the recommended values. The analysis of the reliability levels of structural members designed with the Eurocodes using the NDPs chosen by the Member States, complemented the statistical analysis of the NDPs, providing a more global assessment of the combined impact of the national choices on the levels of safety achieved.
The results demonstrate that the Eurocodes have achieved a high level of harmonisation in the EU and EFTA Member States, since most countries accepted the parameters recommended in the Standards. In fact, the analysis performed with a data availability of 71%, shows a mean acceptance rate of 73% for all NDPs with recommended values. The high rate of acceptance of the NDPs does not automatically imply that these NDPs shall be eliminated in the second generation of the Eurocodes, since many of them are directly related to the safety which is under national responsibility, or account for local geographical, geological and climatic conditions.
Nevertheless, it is of primary interest for the achievement of a deeper internal market for construction products and engineering services that further harmonisation in the use of the Eurocodes is attained, as foreseen in the second generation of the Eurocodes. There are still a number of NDPs in the standards that have a good potential to be considered in the works on the second generation of the Eurocodes, as these NDPs are accounting for different design cultures and procedures for structural analysis. The cross-border convergence of the national maps for climatic and seismic actions shall be considered as an indicator for the harmonised use of data and methods for derivation of these maps.
Harmonising the use of the Eurocodes in the EU and EFTA Member States, by reducing the number of Nationally Determined Parameters in the standards, will reduce the obstacles arising from different national practices and will boost the free circulation of products and services within the European Economic Area.