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| CLOSE
Venues in 2004 Summar Olympics may finish just barely
before games begin in August. (Photo courtesy of Nikos
Daniilidis) |
Preparations for
the summer Olympic Games in Greece, set to begin Aug. 13,
are so late that the prime minister took personal responsibility
for their timely completion just after winning this months
elections. Last-minute construction is most critical at the
crowning main stadium in Athens. Even with nonstop work, its
304-meter-span arching roof will be ready only weeks before
the globally televised opening ceremony is set to take place
under its cover.
After meeting Prime Minister Costas
Karamanlis, Jacques Rogge, president of the International
Olympic Committee, said recently "there is still time
for the preparation if all energies are mobilized." At
the stadium, nobody doubts the urgency. "Can you imagine
an Olympic Games with the steel structure unfinished on top
of the stadium?" says Leonidas Kikiras, project coordinator
for the stadium complexs architect, Santiago Calatrava.
"Its a nightmare."
Before workers can install more
than 2 hectares of polycarbonate roofing and hook up equipment,
next month they must slide the two halves of the 77-m-tall,
18,000-tonne structure over stadium seating. "Other companies
have slid more weight, but this thing is so high. Its
still a risk factor," says Petros Stavrou, construction
manager with main roof contractor Aktor S.A., Athens.
With its bridge-size arches, the
roof is "a very symbolic issue," says Costas Cartalis,
the culture ministrys general secretary for the Olympic
Games. He labels as "extremely unfair" the pall
that has spread over other preparations by the stadiums
notorious progress. "Everything will be completed [on
time]," Cartalis says. "The focus now is on all
elements that make the games really successful, or really
a mess."
Around Athens, many Olympic venues
are visibly well-advanced. All 2,300 apartments at the Olympic
Village are to be handed over to organizers in May. A contractor
is installing 9,000 seats at the wrestling center, having
begun construction 17 months ago. About 30 out of a total
of 40 venues are either complete or more than 90% built, say
Cartalis staffers. The main stadium complex and a soccer
field in Piraeus, both less than 80% ready, are the least
advanced. Transportation links are mostly in place, but work
continues on the 27-kilometer tramway. The 32-km suburban
railroad along the airport expressway wont likely open
before July.
But even Cartalis agrees that valuable
time was lost after Athens won the right to host the Games
in late 1997. The initial ill-fated policy of extensively
privatizing venue developments took up much of the first two
years. "A number of projects were tempting from a finance
and exploitation point of view...but it didnt work out,"
he says.
Political indifference and legal
and bureaucratic obstacles were rampant then, says George
Leventis, the first director general of construction for the
Games Athens Organizing Committee. "By mid-1999,
it became evident to us that it was not working," says
Leventis, a principal at Langan Engineering and Environmental
Services Inc., Elmwood Park, N.J.
In 2000, "the government took
over, and the master plan was updated with a clear view to
use the games as a catalyst for urban development," says
Cartalis. Local objections then hindered planning, adds Sotiris
Douros, a former mayor of the municipality containing the
Olympic Village. Cartalis says he spent most of 2002 defending
49 legal challenges. He won 48.
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| CARTALIS |
STAVROU |
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| (Photo
by Peter Reina for ENR) |
With the slow buildup, construction
of many projects began only in 2002, although work started
earlier at the Village. Because of hurried preparation, design
proceeded after construction started. "Designs existed,
but they needed clarification," says Douros, now a government
technical adviser. "They were not [fully] available during
the tender." Resulting cost hikes have been widespread
but within the budget, claims Cartalis.
With a current $4.5-billion budget,
95% for Athens, the Olympic facilities represent a vast investment
for a nation with fewer than 11 million people. The public
commitment now is many times higher than at the start, when
the entire budget, including nonconstruction elements, was
about $2 billion.
Design changes at the 37,000-sq-m
shooting center outside Athens added 10% to the $62-million
cost, says Costas Arvanitakis, main contractor Alte S.A.s
project manager. The 18-month project should have ended last
year, but "we had a few extra jobs," he says. But
the cost hike "is not much for such a project,"
Arvanitakis adds.
At the stadium complex, an extra
$30 million has been allotted for the main roof, but further
claims are pending. The main contractor, Aktor, and its Italian
steelwork subcontractor are in arbitration over costs related
to the projects rocky past. The Calatrava-designed roof
is the Games boldest element. By adopting his daring
design, the government made "an historic decision,"
says Dimitris Kallit-santsis, Aktor managing director.
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| RISKY
Calatrava-designed stadium roof was a bold move for Greece
(top) but it has been tough for contractors. (Graphic
above courtesy of Santiago-Calatrava S.A., photo below
by Peter Reina for ENR) |
The main roof is in halves, each
supported by two arches, one above the other. With diameters
of 3.2 m and 3.6 m, respectively, the upper and lower tubes
merge at a common "shoe" at each end. Weighing 550
tonnes each, the hollow steelwork shoes are 6.5 m high, 11
m long, ultimately supported by piled slabs.
Cables from upper arches suspend
roof girders and help support the lower tube. The tubes
main function is to counter, with up to 15,000 tonnes of torsion
each, out-of-balance loads from the roof that curves over
the long banks of seats on either side of the stadium.
The roof halves, which connect
only at each end, consist of tapering, inclined steel truss
ribs that weigh 15 tonnes, on average. Bolted at right angles
to the lower tube, their lengths increase from mid-span outwards.
Cantilevering lengths toward the field range from 5 m to 55
m, while the corresponding opposite projections are 32 m to
11 m.
Kallitsantsis own motivation
in leading Aktor to the contract was partly to gain international
kudos for succeeding with the remarkable roof, he says. The
countrys largest construction firm tried unsuccessfully
to find an international contractor to share the risk. Even
knowing that failure would give Aktor "a bad name in
Europe," Kallitsantsis urged its management to bid alone.
From the start, the roof project
faltered when a disappointed consortium challenged its exclusion
from the bidding process, says Cartalis. With the ensuing
legal battle, "a project that had a comfortable timetable
suddenly lost eight months," he says. Firms that did
prequalify in April 2002 submitted bids that summer, but all
broke the budget, says Stavrou.
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| FINISH?
Velodrome roof will be slid into place any day
now at summer games construction site. (Photo by Peter
Reina for ENR) |
After negotiations, Aktor signed
a contract the following November. Its work at the main sports
complex includes covering seating areas of the 22-year-old
main stadium and installing a similar, 3,500-tonne cover on
the existing oval velodrome nearby. Landscaping and other
work raised its contract total to nearly $250 million, not
counting disputed extras.
In the first months, the team developed
outline designs used for bidding. "The contract was awarded
[even] before wind tunnel tests," says Stavrou. A major
design change enlarged the roofs upper and lower tubes
by 0.3 m and 0.4 m, respectively, in exchange for better buckling
resistance, says Calatravas Kikiras. "That had
important impacts on the weight," he adds.
While designs continued, the roofs
fate remained uncertain. Having to move such large arches,
"the magnitude created fears," says Kikiras. "Only
after last July [were] all the participants convinced the
structure was safe, feasible and could be built on time."
Aktors Stavrou adds that the firms familiarity
with other contractors on the job allowed it to promise owners
that the team could meet the deadline.
Aktors Italian subcontractor,
Costruzioni Cimolai Armando S.p.A., Pordenone, had an initial
$75-million contract to fabricate and erect the main roof,
but the total will be significantly higher, according to Salvatore
de Luna, its commercial director. Fabricating the steel at
four of its five Italian plants, Cimolai regained some lost
time by doubling tube erection supports to raise both sets
almost simultaneously.
Cimolai began by raising, with
the use of cranes, parts of each top arch on five temporary
towers on either side of the stadium. Other stadium work prevented
erection at the final positions. With tower-top strand jacks,
the contractor then raised preassembled intermediate sections.
Each lower arch was similarly built, and upper and lower tubes
welded together at their ends.
After main cables between the top
and bottom tubes of the west roof were stressed, the weight
of the arches was recently transferred to its supporting shoe,
and the towers removed. Workers are now bolting roof ribs
to the lower tube, supporting them on a second set of towers.
Cables between the top arch and ribs are being simultaneously
added and partially stressed. Final stressing will start in
May when polycarbonate roofing is applied. Work on the east
roof follows closely.
With current progress, Cimolai
is set to slide both roof assemblies an average of 65 m over
the stadium bowl. Powered by horizontal jacks, the shoes will
slide on stainless steel-lined tracks until the arches are
over the innermost seats, about 140 m apart. Set for April
14 and 24, the slides should take about 10 to 12 hours each,
but Aktor has allotted four days in case of snags.
Until now, Cimolais workers
have concentrated on welding and bolting inside the arch tubes.
Roof erection has seemed quiet, raising press complaints of
inactivity. But a furious de Luna insists that Cimolai is
"working day and night with 150 people and 10 cranes."
As time passes, project principals admit to sleepless nights
of anxiety. But racing to an adrenaline-fueled conclusion,
says Aktors Kallitsantsis, "is the Greek way."
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