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| MEMORIAL
HALL Architectural gem gets costly, structurally
unobtrusive retrofit. (Photo courtesy of William Porter)
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For
years, many national contractors steered clear of construction
work at the University of California's Berkeley campus, citing
contracts that even school officials described as risky and
unfair. But when the university launched a $1-billion-plus
seismic retrofit program four years ago, they knew they needed
moreand more qualifiedbidders to save taxpayer
money. So they began experimenting with contracting strategies
new for the public campus. Unfortunately, the experiment may
not be working as well as expected financially, based on experiences
on UC's first seismic project now under way. Contractual disputes
appear to be as complex as the task of removing the foundations
of an historic brick building just yards from a dreaded fault.
In a 1998 industry speech,
Jeffrey Gee, UC-Berkeley's former director of design and project
management, promised "a big paradigm shift in the way
we've been doing business with contractors." The campus'
adherence to lump-sum contracting and hold-harmless clauses
kept many of the area's most highly qualified designers and
contractors away and often escalated project costs. He sought
instead to employ a blend of construction management and general
contracting that would allow team members to collaborate better
and identify pertinent risks sooner.
To launch the approach, Gee, now
a vice president at San Francisco-based Degenkolb Engineers,
chose a high-profile projectthe challenging retrofit
of UC's nearly century-old Hearst Memorial Mining Building,
used for instruction. The technically complex upgrade "was
the first major project in the shop...that lent itself to
a way of thinking of a new model of delivery," adds Robert
R. Gayle, a former UC project manager on the structure who
succeeded Gee.
But results since work began in
the 1990s have given participants an education in the realities
of construction. Originally estimated in 1993 to cost $51.2
million as a base isolation project "of average complexity,"
according to UC officials, the project rose to $67.6 million
in 1997 for more historic preservation. Last July, the total
was increased to $80.6 millionand counting. Retrofit
completion, set for last October after an extension was granted,
is now months behind. Plans call for work to finish in July.
But the Oakland office of Turner Construction Co., the project's
CM-GC, may face liquidated damages of $5,000 per day since
the Oct. 1 deadline.
HAT TRICK. Built on more than 70
change orders so far, the four-story mining building rests
on an elaborate new foundation. Without the luxury of any
preexisting steel columns to work with, crews placed the building
on a grillage of cast-in-place concrete beams set on base
isolators. "This is an amazing hat trick for the university,"
says Brendan Kelly, a senior associate in the San Francisco
office of NBBJ, which designed the renovation. In January,
UC officials held a ceremony to symbolically unlock the isolators,
to cushion all the weight of brick walls up to 7 ft thick.
Unlike other base-isolation retrofits
elsewhere, the project lacks any substantial new framing from
the ground floor on up, despite concerns for safeguarding
the building's architectural history.
Team members show off the renovated
Memorial Hall atrium, with its vaulted ceiling and Guastavino
ceiling tiles like those in New York's Grand Central Terminal.
But they admit that major construction problems happened below
grade. Crews excavated the building's basement in mining-like
conditions during the wet 1999-2000 winter. "The logistics
of material movement under that building were quite challenging,"
says Grant Griffanti, Turner's senior project manager in Oakland,
Calif. Turner ended up mired in delaysand working through
the process of alternate dispute resolution.
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| (Photo
and graphic courtesy of NBJ/Photo Marion Brenner, photo
manipulation by Nancy Soulliard for ENR) |
Although
Griffanti declines to elaborate on the substance of the dispute
with UC, he says, "We feel that the contract we signed
says one thing and they feel it says another." But he
and colleagues hesitate to air much dirty laundry in what
they view as an architectural, structural and construction
tour de force. "It's going to be a very successful projectI
wouldn't want the contractual issues to put a cloud over the
entire performance," says Danny Cooke, Turner's operations
manager. "It's too soon to tell from a commercial aspect."
Turner played the role of guinea
pig in UC's adoption of the CM/GC method. In November 1998,
the firm began building the Hearst project on change orders,
self-performing 10% and receiving 7.1% for base amount "amendments"
but just 5% fees for "scope changes." UC's Gayle
denies that the fee scheme encouraged campus officials to
low-ball the base sum. He points out that the current dispute
does not concern the fee scheme; instead, delays are due to
"excavation and demolition in very constrained spaces."
Last August, Mike Iker, Turner's regional sales manager, told
ENR: "The interesting thing about that job is it's like
working in the bowels of hell."
But UC regents now warn that "additional
campus funds beyond the [2001] budget increase currently requested
will be required to sustain construction progress to completion
under the conditions of dispute now prevailing."
The regents gave several reasons
for last year's budget increase. They cited "numerous
unforeseen conditions" as in the roof and floors; more
"sub-surface rock beyond that anticipated"; "uncompetitive
market conditions" in the Bay Area's subtrades back in
1998 with bids that "substantially exceeded the pre-construction
cost estimates"; and an extent of work that "had
not been fully defined in the architect's contract documents."
From the start, Gayle and others
wondered what to expect in a 135,000-sq-ft building that first
opened in 1907 with minimal foundations: spread footings,
with some walls directly on rock. Unknown conditions also
existed above. With a 183- x 186-ft footprint, the light-filled
building originally contained spaces tall enough to accommodate
mining rigs. But a 1948 renovation inserted an additional
10,000 sq ft of floor space that has now been removed. Without
two new wings that add back the 10,000 sq ft, the building
lacked any vertical framing other than unreinforced walls.
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KNIT
Needle beams provided temporary support, threaded through
old brick. (Photo courtesy of Turner Construction Company)
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Designed as a memorial to 19th-Century
mining mogul and U.S. Sen. George Hearst, the building's design
reflected a confidence in masonry's rigidity. But according
to local legend, students discovered the highly active Hayward
seismic fault while practicing quarrying operations next to
the building. Seismologists now predict a magnitude 7.2 quake
on the fault with ground accelerations of 0.7 g. To keep retrofit
costs down, UC decided to accept the likelihood of significant
but hopefully reparable damage to the building's nonstructural
systems in such a quake. Still, they directed engineers to
keep the structure occupiable after a magnitude 6 quake with
0.48 g.
The retrofit posed considerable
risks. Above grade, engineers pretty much left the structure
alone except to add perimeter beams to secure floors to walls.
All the structural work cost approximately $25 million, yet
"it's what we call a bare' building," says
Harold A. Davis, principal structural engineer in the Oakland
office of Rutherford & Chekene. He considers it the first
such retrofit without any new shear walls, bracing or other
such strengthening, and one of the few with a foundation replacement.
Davis proceeded with an awareness
of cost overruns on other base isolation retrofits, where
lead engineers specified means and methods for transferring
a building to a new foundation. For the Hearst retrofit, he
and UC decided to try to save money by relying on the contractor's
judgment.
But the university took its time
in choosing whom to hire and how, critics contend. "This
is the first project on campus to use the CM/GC method...it
wasn't adopted in a sufficiently timely manner," UC's
Gayle admits. Rather than hire a CM to provide input from
the start of design in 1996, UC waited until 1998 to solicit
bids, then looked at fees proposed by Turner and Rudolph &
Sletten, Foster City, Calif. Rejecting them, UC started over
with a revised definition of "general conditions,"
meaning the use of onsite managerial staff. Turner then submitted
a bid of 7.1% for fees and general conditions, compared to
R&S's 11.16%.
Not that UC officials gave Turner
time to provide preconstruction services. "There really
wasn't a CM function; there wasn't that opportunity,"
Gayle says. But he emphasizes that using the CM/GC method
opened up more opportunities for a dialogue with Turner about
how best to transfer the building onto a new foundation.
Former construction chief Gee
contends "there were opportunities potentially to define
some middle ground, to finish in December instead of this
summer, and to make everyone a little more whole than they
will be now." But he still sees much value in the project
delivery method. Although it failed to work as well as possible
because the campus did not hire Turner soon enough during
preconstruction, CM/GC can help contractors, especially those
that self-perform just a small portion of work, to assess
risks sooner and adequately prequalify low-bid subcontractors,
says Gee.
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| Base
Isolators (left) sit on new pile caps among temporary
steel (top left) that underpinned building for new basement
and first floor (right). (Photos courtesy of Turner Construction
Company) |
Since letting that contract, the
campus has used the method on four other retrofits with a
combined value of $75 million. All have been under Rudolph
& Sletten's control, and all have remained within budget,
Gayle says.
"To me, it's a win-win
situation for everyone involved," says Ken Brickwedel,
Rudolph & Sletten senior project manager on campus. The
CM/GC method makes public-sector work "more of a private-sector,
streamlined project," he says. Although campus and company
officials have not agreed on all requests for change orders
and time extensions on other campus retrofits, CM/GC has worked
well for handling unforeseen conditions such as buried sheet
piles, Brickwedel says. By giving responsibility for preconstruction
services to the contractor rather than to a third-party cm,
the approach has fostered a non-exploitative relationship
with UC.
On the Hearst building, the once
hellish site conditions have given way to signs of progress.
Crews excavated as much as 28 ft to add a new first floor
and basement and drilled in 687 concrete-filled steel piers.
Despite few opportunities to make up lost time, they underpinned
the building and installed 132 high-damping elastomeric rubber
base isolators, each 30 in. high and designed to shear horizontally
as much as 28 in.
Pleased with the work and the
minimal cracking of masonry, Gayle praises the "extremely
productive relationship" between UC and Turner in a "well-behaved
dispute." While he concedes that "there are significant
dollars at risk," he is unconcerned about possible fallout.
"I'm not aware of any deterrent effect," he says.
"We want to be seen as a good partner." Gayle says
other A-list contractors such as Charles Pankow Builders Ltd.
and M.A. Mortenson Co. now do business with UC-Berkeley. "These
are names that you would not have seen on our campus 10 years
ago," he says.
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