39
d
&
ri
MAY-JUNE 2015
SITE REPORT
of oil-filled transmission cableswith
polyethylene replacements –work that has to
be completed throughout Belgiumby2020.
TheZeebruggeproject included the
demolitionof twoheavily reinforced storage
tanks, eachofwhichonce contained5million
litres (1.1milliongallons) of kerosene. Each
was buriedunder 1m (3.3 ft) of sand, andhad
a 60 cm (2 ft) thick reinforced concrete top
plate and slightly thinner reinforced concrete
sidewalls.
In addition to the tanks, therewere two
heavily armoured reinforced concretebunkers
that housed thenecessaryhighpressure
pumps that transferred the fuel through the
pipelines, and anumber of other buildings
around the site, includingguardhouses and
associated residential structures. In addition,
all theunderground cables andpipes had to
be found anddugup, and at the endof the
demolitionphase, the sitehad tobe totally
clean and exactly level.
In a first for the region, Princen recently
tookdeliveryof the firstVolvoEC480D
HRhigh reachdemolition excavator tobe
deployed in theBenelux countries along
with associatedDehaco attachments. It is
equippedwith a short, straight boom and arm
configuration. Thiswas deployed to the site to
dealwith thephysical demolitionof themore
robust structures.
According tooperator andownerWesley:
“With the short boom, I have apinheight of
14m andbecauseof themachine’sweight of
63 tonnes, additional counterweight and4
m trackwidth, I canworkwith a 4.8 tonne
crusherwith excellent stability,”Wesley
added. “I also like thehydraulically variable
undercarriage andVolvo’s hydraulic joint,
whichmakes tool changes quick and easy.”
Ground conditions had an impact on
Princen’s selectionof theother earthmoving
equipment on the site. The companyopted
for trackeddumpers insteadof articulated
haulers tomovematerials during earthmoving
operations, since inwet conditions the
ground surface veryquickly could turn into a
quagmire because of its claynature, a fact that
was not helpedby the fact that the ground
surface inmanyplaceswas very close to, if not
at, the groundwater level.
Leveling the sloping sitewithheight
differences of up to3m (10 ft) involved the
recycling of some 12,000 tonnes of concrete
and50,000m
3
of earth.
Given the clay conditions andhighwater
table, the ground surfacehad tobeprepared
for the constructionof thenew substation,
whichwill require covering the entire site
with sand0.7mdeep. The sandused for
thiswas recovered from the site and stored
until theworkbegan - in total, 95%of the
materials used to level the sitewas recycled.
Theproject began inmid-December 2015 and
thedemolition and the clean-upphasewas
completedon schedule.
■
Reaching
high
When fitted with its 27m (88.6 ft) high
reach boom, the Volvo EC480DHR can
carry an attachment up to three tonnes.
Safety features include boom-and-arm
holding valves, forward and rear view
cameras, as well as roof and front screen
protection. It also has a Total Moment
Indicator that warns the operator if the
machine approaches themaximum safe
working load. For enhanced visibility and
reduced operator fatigue when working at
high reach, the tilting cab pivots up to 30°.
When not required for high reach work,
themachine’s boom can be switched from
its demolition equipment to a standard dig
boom and arm in just 1.5 hours.
The one remaining fuel storage tank on the site
at the time of D&Ri’s visitwas heavily protected
by thick reinforced concretewalls and alsowith
a thick covering of sand, which Princen had to
remove before starting the demolition
Once cleaned and remediated, the ground
surface is very close to thewater table so a 0.7
m layer of sand is being laid across the entire
site prior to construction beginning.
One of two oil tanks thatwere originally
buried under the surface for protection and
which proved a challenge to remove
In addition to the 4.8 tonne Dehaco , Princen also acquired a newDehaco SH550R shear for the new
Volvo to allow it to process themetals from the site
