Tensar Wall System Means Cost Savings On The DLR

On the Thames Wharf section of the £143m extension toLondon Docklands Light Railway (DLR), the Tensar Wall System was selected for the construction of two bridge abutments and associated wingwalls.

On the £143m extension to the London Docklands Light Railway (DLR) from Canning Town to North Woolwich, contractor AMEC needed to construct 4.5km of largely elevated twin track railway.

On the Thames Wharf section of the project, the Tensar Wall System designed and supplied by Tensar International was selected for the construction of two bridge abutments and associated wingwalls.

"Tensar's system is a lot quicker than alternative methods such as reinforced concrete, and the facing units do not require specialist lifting equipment as they are easily handled," said AMEC senior engineer Tim Haylock.

For both economic and environmental reasons AMEC chose to use recycled crushed concrete graded to a Type 1 specification as the reinforced fill for the abutments and wingwalls.

The Tensar solution was chosen primarily on economic grounds, but also as an alternative to a galvanised steel strip reinforcing solution which would have corroded as the crushed concrete fill has a high sulphate content.

Use of Tensar geogrids was possible because they are manufactured from high-density polyethylene which is exceptionally inert and highly resistant to chemical attack, including sulphates.

Tensar's abutment and wall system has British Board of Agrement (BBA) certification for 120 year design life and consists of modular pre-cast concrete facing blocks and layers of geogrid which reinforce the granular fill.

The geogrids are connected to the block wall by a unique high strength polymer "key".

Pea shingle was used behind the blocks for drainage purposes.

Wall System units are available in a variety of colours, styles and finishes.

They are manufactured from high-quality pre-cast concrete and are easily handled, dry-bedded and locked together with a single shear connection.

AMEC chose a standard flint block with a split face finish which gives an attractive exposed aggregate appearance.

Tensar also offer a block wall system specially designed to allow a facade of architectural masonry or brickwork to be secured using stainless steel wall-ties is available, where the site demands.

The walls are designed to Highways Agency Standard BD 70/97.

The blocks and geogrid components are all designed for one-man lift.

Back to top