In 1978, the UK Government announced its decision to commission a new national library. The old library at the British Museum had long since outgrown its Bloomsbury home, with much of the collection being housed in poor-quality storage 10 miles away. The new library would bring these and other important national collections together in a single, purpose-built building. Designed by Sir Colin St John Wilson with 120,000m2 of space over 14 floors, the new British Library would be the largest public building constructed in the UK in the 20th century.

Arup was challenged in designing the foundation for the new building, which would have to reconcile a complex set of conditions. Five levels of basement would run 24 meters below ground and support nine levels of public reading and office space above, plus the enormous weight of the books themselves. The site would have to cope with London’s chalk and clay layers and their natural capacity to shrink and swell. On top of it all, the geotechnical teams would have to plan around the Northern and Victoria underground lines running below the library. 

When it opened, the library was home to 120 million books and print items, from da Vinci’s notebook and the world’s oldest printed document to today’s newspapers. The foundation and supporting columns that Arup designed had to support that weight, as well as the operations of a busy institution and attraction, and the coffered slabs that form the library. With over 500,000 titles being added each year, Arup’s design had to optimise use of space. 

Sketches showing the basement which runs 24 metres below ground – the equivalent of an eight storey building – and reach as deep as the Victoria line which runs alongside them.

Geotechnical & geotechnics services 

For the supporting columns, our team used cased steel sections as well as reinforced concrete. They were able to reduce the column sizes to match the width of the library’s bookstacks, creating a much more efficient layout. Today, the library’s collection has grown to over 170 million items, all supported by these space saving columns. In 2015, the library was awarded Grade 1 listing for its architectural interest and the craftsmanship of its construction. 

Computer modelling and finite element analysis were in their infancy in the 1970s. Our geotechnical team had developed their own finite element computer programme, SAFE, to model and test how the foundations would behave faced with these challenges. The team were also able to accurately and confidently predict any likely movement of the tube tunnels and surrounding buildings. 

The British Library, Arup
With over 500,000 titles being added each year, Arup’s design had to optimise use of space