Brownfield sites - green light

Foamed concrete gives brownfield sites the green light

Since 2010 the government has been taking steps to prioritise the use of brownfield sites for new building developments. When Chancellor George Osborne announced that 200,000 new homes could be built if planning permissions were relaxed on these developed sites, brownfield became the key to getting Britain building again.

By removing the red tape around 5,000 hectares of brownfield land, the UK can meet the growing demand for new residential and commercial properties while protecting green spaces for the future. But with these sites often made up of vacant or derelict buildings, how can we prepare them for redevelopment? Propump Engineering has a simple and economical solution – lightweight foamed concrete.

Foamed concrete is a free-flowing, self-compacting, and highly insulating material. Already a well-established material in void-filling and highway reinstatement, it is also ideal for soil stabilisation and brownfield remediation and can efficiently and economically breathe new life into these once ‘unbuildable‘ pieces of land.

As an extremely versatile product, foamed concrete can also flow through small enclosed voids such as sewers and yet when set can be tooled to provide access for services. And with a flexible and speedy process, foamed concrete is used as it is delivered and can be poured in 1 metre lifts for a smooth and efficient application.

Produced with densities as low as 375 kg/m3 in situ, it can still provide exceptional strength as high as 20 Newton. So whether the brownfield site has disused sewers that require filling or existing foundations that need re-strengthening – foamed concrete offers a lightweight but strong solution for preparatory regenerative work.

For quality management, foamed concrete is also very hard to beat. Produced using an innovative process which allows total control over each element, this allows much greater management of the final result and ensures the highest quality material is supplied.

Breaking new ground
At the £400 million Bridge Estate development in Dartford, Kent, Propump supplied 15,000m3 of foamed concrete to stabilise a new roadway and food distribution centre car park – built on a 264 acre brownfield site near the Thames Estuary.

The site of the new road was a mixture of made up ground from previous quarrying activities with soft peat and clay beneath. Standard road construction materials would have caused consolidation and settlement of the finished road, so to avoid this, the made up ground was excavated and replaced with Propump’s quality assured foamed concrete.

As the new roadway was also being built on ground with a high water table, Propump had to ensure the foamed concrete supplied had a heavier density than water – approximately 1000kg/m3. For this, the company supplied 1100kg/m3 density foamed concrete to complete the first UK application of foamed concrete to support a road this size, more than 1 kilometre in length.

Following this successful installation, Propump was appointed to create a sub base for further extensions to the road, as well as a solid base to enable the construction of a block paved car park for a new-build food distribution centre. Built on land less susceptible to flooding, Propump produced and installed 500kg/m3 density foamed concrete.

With enough previously developed brownfield land across the UK to deliver up to 200,000 new homes – restoring vacant, derelict or contaminated land will play a key role in the government’s long-term economic plan. By turning to lightweight and high performance foamed concrete from Propump Engineering, developers can provide a solid base for the on-going revival of the UK construction industry.

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