Below ground waterproofing to the perimeter retaining walls of Royal Liverpool Hospital, as well as across the entire sloping site. Additional protection was also required for the lift pits and a link tunnel for this project.

The challenge

Value engineering the waterproofing of over 1200m3 of concrete across the entire site of this new state of the art hospital. A 25 year warranty required by the client upon completion, therefore longevity was key.

The initial construction phase included the retaining walls around parts of the perimeter. A second phase extended to an underground tunnel requiring a Grade 3 (BS 8102:2009). Waterproofing was required for all elements (slab, walls, suspended roof slab).

The Xypex solution

Xypex Admix was used for all retaining walls requiring watertight specification.

With the additional ability to provide protection from aggressive chemical contamination, including salt, Xypex was the perfect stand-alone solution for this site. This enhanced resistance ensured durability within the concrete, without the need for secondary solutions or costly post-build remedial works.

The slip formed lift pit core also included Xypex, where it was used below ground.

Xypex Admix C Series – Retaining walls, lift pits, tunnel base and walls and suspended roof slab within tunnel

Xypex Concentrate – All joints

Hydroswell Bentostrip – All joints

The results

By not limiting pour size or aspect ratio, the use of Xypex Admix ensured concrete placement was quick and efficient. This reduced the number of joints required, in turn helping to keep the project on schedule and minimising costs.