Eurocode standards

Stability calculations are inextricably linked to “standards”.
“Standards” contain rules relating to the design of structures. They are usually imposed by the government.
In Europe, we use the “Eurocodes” as the standard during a structural analysis.

A brief history of the Eurocodes

The development of the Eurocodes began in 1975 following a decision by the European Commission. The first Eurocodes were published in 1984. In 1990, the preliminary standard ENV was published. In 1998, the conversion from ENV (preliminary standard) to EN began. By 2007, the EN series (as we know it today) had been published in its entirety.

Purpose of the Eurocode

The objectives of the Eurocode are:

• ensuring structural safety (strength, stability and rigidity)
• achieving uniformity in calculations across Europe
• harmonising national regulations
• creating a uniform basis for research and development
• simplifying the exchange of services and products within the European construction industry

If a structure does not meet the requirements for structural safety, it may collapse, resulting in considerable damage and/or casualties.

The Eurocodes are adopted by all EU countries and some neighbouring countries that are also CEN members: Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic, Denmark, Estonia, Finland, Germany, Greece, Hungary, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Poland, Portugal, Romania, Slovakia, Slovenia, Spain and Sweden. However, the Eurocodes are more established in some countries than in others.

Several other countries have also adopted (parts of) the Eurocodes or are in the process of becoming CEN members.

The Eurocodes are published by CEN in three languages: English, French and German.
Most countries that use the Eurocode choose to translate (some parts of) the Eurocodes (or only the national annexes) into local languages.

The structure of the Eurocode

The Eurocode suite consists of 10 standards, numbered EN 1990 to EN 1999. Each standard covers a general topic (see image below).

Each of the standards (except EN 1990) is divided into several parts that deal with specific aspects of the subject. In total, there are 58 EN Eurocode parts spread across the ten Eurocodes (EN 1990 – 1999).

All EN Eurocodes relating to materials have a Part 1-1 dealing with the design of buildings and other civil engineering structures, and a Part 1-2 for fire design. The standards for concrete, steel, steel and concrete composite, and timber structures and earthquake resistance have a Part 2 on the design of bridges. Part 2 must be used in conjunction with the applicable general parts (Parts 1). For example, when designing a steel bridge, we need EN 1993-1-1 (design of steel structures). But we also need EN 1993-2 (specific rules for the design of steel bridges). To determine the loads, we need EN 1991, and for the foundations, we need EN 1990. So it is not the case that we only need one part for the design.

Maintaining the Eurocodes is essential to preserve their credibility, integrity and relevance, and to ensure that they do not contain any errors. Over the years, corrigenda or amendments have been published for certain Eurocode parts. The name of each Eurocode is followed by the year of publication. For example:

• EN 1993-1-1:2005 is the European standard for the design of steel structures, published in 2005
• EN 1993-1-1:2005/AC: 2009 is the corrigendum to the European standard for the design of steel structures, published in 2009
• EN 1993-1-1/A1: 2014 is the first amendment to the European standard for the design of steel structures, published in 2014

In national annexes (NA) to the Eurocode, countries can fill in a significant part of each Eurocode using NBP (nationally determined parameters). A national annex to a Eurocode is indicated by a country code followed by the name of the Eurocode. For example:

• NBN EN 1993-1-1 ANB:2018 is the Belgian national annex to Eurocode 3, part 1-1, published in 2018.
• NF EN 1993-1-1/NA: 2007 is the French national annex to Eurocode 3, part 1-1, published in 2007.

When a Eurocode component is updated, the national annex is also updated (if relevant). It is important to check that you are using the latest version of the Eurocode and that the corresponding National Annex has also been updated.

Challenges in Eurocode

Although the principle of uniform calculations throughout Europe sounds like music to the ears, the Eurocode also has its challenges.

The text is not a step-by-step guide, but is often written by specialists who assume a certain basic (or sometimes advanced) level of knowledge on the part of the reader.

Compared to its predecessor (the ENV), the first generation of EN Eurocodes omitted a lot of background information about the origin of the calculation rules.

The current Eurocode dates from 2007, but technology has not stood still. The Eurocodes and national annexes are sometimes behind because the update process is time-consuming. The second generation of EN Eurocodes is currently being written.

The complexity of the Eurocode makes knowledge of structural analysis and a willingness to never stop learning essential. An office library, exchanging opinions with colleagues, training courses, calculation examples, research into older versions of standards, experience… these are underestimated tools for an engineer.

Eurocodes in the future

Work on the second generation of Eurocodes officially began in 2015 and is expected to be completed in 2026 (without national annexes). All new Eurocodes (with national annexes) should be published by 30 September 2027, and the first generation of Eurocodes will be withdrawn by 30 March 2028 at the latest. Between 30 September 2027 and 30 March 2028, the first and second generations of Eurocodes will coexist.

National standardisation bodies are already working on national annexes to the new Eurocode parts that are already ready. During the drafting of the new Eurocodes, strong emphasis was placed on greater ease of use in order to obtain a more user-friendly set of design standards.

The second generation will include improvements to the existing design rules, but its scope will also be extended to include new materials such as structural glass (the future Eurocode 10) and fibre-reinforced concrete. Robustness requirements will become more important, as will the reuse and adaptation of existing structures.

How Buildsoft is preparing for the second generation of Eurocodes

At Buildsoft, we are closely following the evolution of the second generation of Eurocodes. Our team of engineers and developers is currently analysing the new provisions and performing extensive calculation examples to understand the impact on structural analysis. Based on this, we are working step by step to implement the updated standards in our software, so that our users can switch smoothly as soon as the new regulations come into force.

In addition, we are preparing information material and training courses to provide our customers with optimal support during the transition. We want to offer not only up-to-date software, but also the knowledge and guidance needed to work confidently in accordance with the new Eurocodes.