Dalmuir Waste Water Treatment Works

Aarsleff completed the installation of more than 300 precast
concrete piles to create the foundations for an extension to a
waste water treatment facility for Saur Services Glasgow at
Clydebank. The project for MWH, the global wet infrastructure
engineering consultancy on behalf of Capita Symonds and Saur,
the operators of the Scottish waste water treatment works, was
completed exactly on schedule.

“I was very impressed with the site crew,” reported Stefan
Erbes, site manager for MWH. “We had prepared the site which
has a lot of made up ground, in line with the platform layout and
specification. However it was found that the operating space
was limited but the Aarsleff crew worked around this problem
and did not lose any time.”

The Dalmuir site treats 378,000m³ of waste water daily and
requires increased sludge treatment capacity. The new sludge
management building holds increased centrifuge capacity to
increase water removal and also to improve the quality of the
waste water discharged under license into the River Clyde. The
new operation will be ready for commissioning in Spring 2015.

The piling design was developed by Capita Symonds in
association with MWH and Aarsleff’s own in-house technical
team. The 335 precast concrete piles were driven into position
by a Junttan PM20 piling rig with a six tonne accelerated hammer
from Aarsleff’s own comprehensive fleet. The project took six
weeks including the associated dynamic testing. 166 piles of
350mm x 350mm achieved loads of 1150KN-1250KN and were
driven between 14m-21metres as were the 155 piles of 300mm
x 300mm which achieved loads of 700KN-800KN. Fourteen piles
250mm x 250mm were driven between 13m-20metres to achieve
loads between 175KN and 600Kn.

Dan Broadley of Aarsleff confirmed that the piling project ran
smoothly. “Although the location is quite remote, access was not
a problem for the rig and the pile deliveries. There were deep
excavations for the base storage facility so we had to carefully
manage the rig movements and the piling action. It all ran
perfectly.”

The Centrum Pile System of precast reinforced concrete piles
installed by Aarsleff are manufactured by subsidiary company
Centrum Pile Ltd at the state-of-the-art facility at Newark,
Nottinghamshire. With headquarters in Denmark, the UK facility
is one of four including Sweden and Poland, which give a
production capacity of 3.2 million metres of piles annually.

Casting is a fully automatic process using bespoke machines
designed by Centrum specifically for pile production with
self compacting concrete which does not require vibration.
Detailed mix and product data records are maintained for full
product traceability, which can be seen on each pile’s barcode
reference.

Piles are manufactured in sizes from 200 x 200mm up to 450
x450mm in lengths from 4m-15metres with the high-grade steel
reinforcement being incorporated during fabrication.