Key innovation: partnering
The work to stabilise LUL's earth embankments is taking place next to a live railway and a formal alliance between Kvaerner and Mott was the best way to maximise safety and minimise disruption. On the East London Line minipiles had to be bored at 1m intervals, 1m into some of the oldest embankment on the network. By rethinking the usual design process a solution was specified that, instead of stipulating a toe level for the pile, required a minimum penetration into the gravel layer. This gave flexibility to operations on site, allowing actual site conditions to determine the pile length rather than an assumed strata profile gained from soil samples. Waste was eliminated in areas where the gravel layer was higher than expected and where it was deeper the full pile length was installed to do the job.
Project team: LUL, Kvaerner Cementation Foundations, Mott MacDonald