Case Study // British Museum

Working alongside Carey’s, Swanton advised and designed the temporary support of the 12m deep excavation during construction of the new World Conservation and Exhibition Centre for the British Museum.

The project incorporated 3/4 levels of propping, which connected to steel walers and concrete beams that restrained the piled wall during excavation and construction. The walers spanned a maximum distance of 11m between supports. Due to high wall loads, twin steel UB sections were utilised.

CHS steel sections were used for props with some spanning just over 25m between the piled walls either side of the excavation. The props on site where staggered so that the onsite tower crane could lift sections in for each level. Larger props were also installed in sections due to their size. Props were designed so that they could be pre-loaded to reduce the movement of the piled walls during construction and meet the requirements as per our brief.

Swanton also conducted the excavation sequencing for the props. This design allowed for excavation past props to allow a greater work area during the installation of the props while minimising disturbance to the excavation works.

We designed both tower crane base grillages, the larger of which spans 15 metres across the deep excavation.