High-visibility hope

Standout bridge receives much-needed paint job

Bridges Article March 18, 2003
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When it was built in 1932, Cleveland's art deco-style Hope
Memorial Bridge was hailed as one of the most beautiful bridges constructed
that year. The historic landmark bridge spans the industrial Cuyahoga River
Valley and is one of four major viaduct bridges that connect the east and west
sides of Cleveland.

Since its last rehabilitation in the early 1980s, sections
of the 3,285-ft-long bridge had deteriorated significantly. Its elegant arched
steel trusses were rusted and damaged by an inadequate water drainage system,
and the huge sandstone sculptures that stand sentry at the east and west
entrances to the bridge were covered with years of dirt and beginning to
spall. 

While Cuyahoga County is responsible for the maintenance of
the Hope Memorial Bridge, in 2000 the Ohio Department of Transportation (ODOT),
District 12, stepped in to fund the $20.275 million, three-year rehabilitation
project because of the project's scope and size. A key objective was to restore
the bridge's appearance and preserve its beauty as an integral part of the
cityscape--a project that would require stripping 1.8 million sq ft of steel to
the bare metal and painting it with a three-coat system. A & L Painting
LLC, Cleveland, was charged with this job. 

Repairs to the structural steel and some of the concrete
work were completed in 2001, while the focus of 2002 was on cleaning and
painting the bridge's steel trusses. The final phase of the Hope Memorial
Bridge project will be completed during the summer of 2003 when the concrete will
be cleaned and painted and the bridge deck sealed with a crack sealer followed
by a deck sealer, making the structure 100% watertight.

Art deco look

The Hope Memorial Bridge's high visibility prompted serious
thinking about the colors to be used on the bridge's structural steel, parapet
and pilasters. ODOT District 12 Design Engineer Natalie Conley, P.E., organized
a team from a cross section of city and state planning commissions and from the
Cuyahoga County Engineer's Office to select and approve the final bridge
colors.

The team turned to The Sherwin-Williams Co. Color Marketing
and Design Department for help. Color and Design Consultant Susan Wadden
developed the color schemes from a palette of historic paint colors. As it
happened, Sherwin-Williams is a Cleveland-based company, and Wadden's office
overlooks the bridge. Using photo-imaging software, she superimposed different
colors onto the bridge's steel trusses, parapet and pilasters.

"Plugging in the different colors gave the committee
members a good feel for what each color scheme would look like," said
Wadden. "We avoided the process of having to apply sample paint colors at
the project site and then wait while the customer reviewed the colors, so we
also saved valuable time."

The committee considered several color schemes and
eventually selected a palette of green and tans. For the structural steel,
Rookwood Dark Green, an olive-green shade, was selected and cross-referenced to
the Federal Standard Color Number 595B-14097.

"Visually, it was a smart color choice as green appeals
to 98% of the population," Wadden said. "The green color also
complements the cityscape. Modular Tan was chosen for the railings, parapet and
fascia, while Crewel Tan, which is several shades lighter, was chosen for the
concrete piers."

The bare metal

Before the first coat of paint could be applied, a
tremendous amount of surface preparation work was required to remove 70 years
of accumulated paint. In February 2002, containment began at the first section
of the Hope Memorial Bridge. To prevent airborne materials from escaping into
the atmosphere and Cuyahoga River below, a containment tarp was custom made to
fit the contours of the bridge. Schott International supplied the tarps for the
bridge project and works exclusively with Sherwin-Williams in the sale and
distribution of custom containment materials. Special cables and brackets were
constructed to support the custom-made tarp, while a steel deck platform was
installed below the steel trusses completing the containment system.

James Tuttle, P.E., vice president of operations for A &
L Painting, explained, "As each section of the bridge is surface cleaned
and painted, the containment cover and all of its support elements move
together to the next section of the bridge to be painted."

In addition, the containment system was specifically
designed to handle wind loads of 50 to 60 miles per hour as well as the weight
of the contractor's materials stored at the project site. "Because of
these preventive measures, there was no lost production time," Tuttle
said.

A & L Painting crews started surface blasting with
recyclable steel grit at the east end of the structure in April and worked
their way to the west end by early October.

"They had to achieve bare metal-SPPC SP-10 near white
blast--with a profile of existing steel between 1.5 and 3.5 mils," Tuttle
said. "To meet the SPPC SP-10 standard, the steel had to be free of all
visible oil, grease, dirt, dust, mill scale, rust, paint, oxides, corrosion
products and other foreign matter, except for staining."

The interwoven design of the steel trusses, and the round
rivets and bolts, presented a challenge for the crews who were forced to blast
from several different angles to strip away the old paint.

"This work was more intensive, compared with blasting a
rolled beam bridge that is one continuous piece of steel with flat surfaces and
no rivets," Tuttle explained.

Layer upon layer

As soon as the steel was cleaned, the first coat of primer
was applied within two hours to provide a protective barrier against future
rust or other corrosion-related problems. The coatings used for the structural
steel were supplied by Sherwin-Williams and manufactured to ODOT's Organic
Zinc, Epoxy and Urethane System specifications. Paint batches were tested and
certified by Sherwin-Williams quality control labs at the plant and tracked
using ODOT's TE-24 (batch tracking) system. As a result, all paint supplies
were registered with the state prior to arriving at the jobsite.

Kelly Tokish, a customer service representative with
Sherwin-Williams, coordinated all the product orders and drop trailer shipments
to the jobsite to ensure that adequate inventories of various materials were on
hand at all times.

Selected for its corrosion-resistant properties, Zinc Clad
IV Organic Zinc-Rich Epoxy Primer was used on the structural steel supports. It
is a two-component, polyamide epoxy zinc-rich coating that features a low VOC
level and 85% zinc content in the dry film.

"The Zinc Clad IV primer provides cathodic protection
to the substrate of the steel," explained Mark Perrings, an industrial and
marine sales manager with Sherwin-Williams. "If the coating system is
damaged and bare metal exposed, instead of rust developing, a fine film of white
powder (zinc oxide) forms and continues to protect the steel's substrate from
corrosion."

Zinc Clad IV can be applied 5 to 8 mils wet (3 to 5 mils
dry) and will be dry to the touch in about 30 to 45 minutes, depending on the
temperature, humidity and film thickness. The organic zinc-rich epoxy primer
can be top coated in only four to six hours.

Approximately 10,000 gal of Zinc Clad IV primer were applied
to the structural steel of the Hope Memorial Bridge. About 36 miles of caulking
was applied to channels and angles, plates, lattice bars, rivets and bolts.

The painting crews then proceeded with applying about 16,000
gal of heavy-duty epoxy intermediate coat. "The purpose of the
intermediate coat is to seal the surface of the zinc, add 5 to 7 mils of barrier
coat protection and provide a suitable surface for adherence of the
topcoat," Perrings said.

Another 11,000 gal of paint were required for the finish
coat--Hi-Solids Polyurethane Gloss--a two-component, low-VOC, aliphatic,
acrylic polyurethane resin coating.

"Given the structure's high profile and visibility to
motorists and downtown office building tenants, it was very important to select
a coating that offered outstanding color and gloss retention," Perrings
said.

The polyurethane offers chemical resistant properties that
will protect the substrate from industrial and vehicular pollution for years.
The recommended application is 4.5 to 6 wet mils and 3 to 4 dry mils. The
coating dries to the touch in two to four hours and can be recoated within 18 to
24 hours.

The quality test

After each phase of surface cleaning and coating
application, ODOT inspectors checked key criteria to ensure specifications were
met.

"There are nine quality control points that ODOT
inspectors monitor, and they cover every phase of the job from blasting to
applying the finish coat," said Patrick J. McCafferty, transportation
engineer, III, ODOT.

"For example, quality control point No. 4 is about
abrasive blasting," he explained. "Inspectors measure temperature and
humidity and calculate the dew point. In addition, they measure the surface
profile of the steel to determine if it is within the 1.5 to 3.5 mils
specified."

If spots are missed during the blasting phase, those areas
are cleaned again and retested in order to pass a particular quality control
point. Adhering to the nine control points helps ensure that quality work is
performed at every step of the entire project.

The structural steel of the Hope Memorial Bridge was cleaned
and painted by Oct. 31, 2002, meeting the project deadline. Final approval of
all aspects of the three-year project, including the painting, will take place
in the summer of 2003.

About the author: 
Pendry is a focus market manager, bridge and highway, for Sherwin-Williams.
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