To capitalise on prime development space, a trend for taller structures is emerging. This requires the use of innovative special concretes with significantly higher compressive strengths to maximise usable space, generate savings and increase productivity.
Laying thinner, stronger material for both the walls and floors not only increases available space, the external envelope and levels of light in the subsequent rooms, but also makes the building weigh less.
Cost savings can be achieved due to smaller foundations and a reduced façade surface, because less material is needed for construction compared with traditional concrete.
Independent research by Arup on real-world projects has demonstrated how self-compacting and high early strength concretes are able to add value to multi-storey developments.
The Arup study showed that efficiency savings can be realised for composite slabs and shear cores for steel-framed commercial buildings as the material can be poured more quickly and requires less finishing than a standard mix. In a 21-storey steel framed building for example this could unlock overall savings of approximately £268,000, with faster construction also allowing earlier access for follow-on trades.
For a 16-storey concrete-framed residential building, the combined savings on materials, plant and labour with the reduced external envelope totals £391,000, representing a cost saving of 8.4 per cent.
If the concrete cores for these types of buildings are on the critical path and constructed using jump-form, using high early strength concrete in this way can potentially offer a 40 per cent time saving for the core construction, translating into a five per cent reduction to the total overall programme.
Being able to reduce element sizes, speed up construction and facilitate easy installation of the product at height by using special concretes all create project cost savings while boosting productivity, maximising space and reducing materials.