timeline item
Results
Here is the information we have
on the item you selected
This entry was funded by
More like this
NEW SEARCH
| |
sign up for our newsletter
© 2017 Engineering Timelines
engineering-timelines@severalworld.co.uk
engineering timelines
explore ... how   explore ... why   explore ... where   explore ... who  
home  •  NEWS  •  search  •  FAQs  •  references  •  about  •  sponsors + links
North Morecambe Gas Terminal foundations
Rampside, Barrow-in-Furness, Cumbria
North Morecambe Gas Terminal foundations
associated engineer
Keller Ground Engineering
date  1991 - 4th April 1992
era  Modern  |  category  Factory/Industrial Plant  |  reference  SD225678
ICE reference number  HEW 579
photo  Keller Ground Engineering
Site preparation and foundation construction for the North Morecambe Gas Terminal on the shores of Morecambe Bay achieved a world first in its innovative solution to the need for foundations designed to withstand seismic forces on a site with unstable ground above potentially liquefiable alluvial sands.
The terminal was constructed for British Gas. It covers some 20 hectares and is associated with the development of the North Morecambe Gas Field, the largest undeveloped offshore gas field in the UK at the time. Development of the gas field started in April 1991 and was in full operation late in 1994.
The site is coastal and consisted of deep lagoons of water-logged pulverised fuel ash (PFA) — waste product from the local coal-burning power station — contaminated with heavy metals. The foundations had to be designed to withstand up to 10,000-year seismic events.
The water-logged PFA could not be removed from site for environmental reasons. The foundation designers, Keller Ground Engineering, used vibro-replacement to overcome the problem of the potential liquefaction of the underlying sands. In this process, a vibrating probe is driven into the ground to the required depth and the resulting column-like hole is backfilled with stone aggregate, which is then compacted to form a stone column deep in the ground.
Short piles were then driven. These were chosen as a means of transferring the weight of the gas terminal to be built above, through the unstable PFA layer to the underlying strengthened ground. All this required heavy machinery on the site and to support the construction plant, a 2m layer of PFA was removed and replaced with a blanket of granular material.
The whole foundation works cost 9m. In the winter of 1991/92, 500,000 cubic metres of the underlying soil was strengthened, overlaid with some 335,000 tonnes of granular material. Nearly 3,500 piles were driven and 2,000 stone columns constructed in the sub-soil.
Keller's solution not only provided a unique answer to the ground problems of the site but allows a degree of flexibility for the evolution of the gas terminal plant built above.
Although the gas works are of course visible (photo above shows the works under construction), the foundations are underground, so cannot be seen. The site is not open to the general public.
Design engineer: Christopher Andrew Raison
Main contractor: Keller Foundation Engineers plc
Research: PD and AJD
bibliography
"Ground Stabilisation and Foundations for the North Morecambe Gas Terminal"
by Keller Foundations, May 1992
(Submission for the British Construction Industry Awards 1992)
Location

North Morecambe Gas Terminal foundations