Norwich Northern Distributor Road

We were engaged on the Norwich Northern Distributor Road as BIM managers and 3d modellers.

Balfour Beatty’s earthworks strategy on the Norwich project was not to take any material off site and limit the amount of material imported to the absolute minimum.

Once the overall earthworks calculations had been carried out it transpired that they had a huge shortfall of acceptable material due to initial survey errors and as such we were asked to take a look at their earthworks quantities with a view to finding them more acceptable material.

The approach we took was to increase the size of ponds and lagoons, widen the areas of cuttings and take material from landscape areas by local lowering. We also reduced the height of some landscaping bunds to lessen the need for material in these bunds.

In order to be able to calculate how much additional material we generated we had to calculate how much material was being generated by the current design and then compare those volumes with our amended design. To calculate the volumes of material won from a pond or lagoon we created terrain models from the top surface of the pond and then compared that surface to the terrain model created from the pond surfaces.

Examples are shown below.

This extract shows an existing lagoon enlarged to extract more acceptable material – the difference between the current design and our design can be clearly seen.

An isometric view of the earthworks model is shown below.

Another enlarged pond showing the additional material won

We also changed the position of a bridleway in cutting to increase the amount of material won from the cutting, as shown below