Commercial Architecture June 2019 - 20

▲

FEATURE

| building technology
Laser scans were used to create an
as-built 3D model, in this case the
concourse, which was then updated
continuously with new data throughout
the years of construction to track productivity, completion, and quality, and
plan for future work.

Wrigley Field. The construction sequence began with

installation. There was never room to have more than

ic marquee sign was reconstructed and rewired, and

retaining-wall installation and load-bearing elements

two or three days of steel ready for installation.

the caretaker's house was preserved to comply with

that carried the future structure. The next steps

When the steel arrived, it was taken off the truck

landmark requirements and moved across the street

involved constructing floor slabs on grade and mining

with a crane, set in place and shored up from below.

while a new foundation was installed and then moved

out the earth below. It provided an added benefit of

This just-in-time prefabrication and delivery process

back to its original location.

simultaneously erecting the structure going up. This

had a tremendous impact on expediting the schedule

Every phase of the project posed significant engi-

process saved money and had the least impact on the

and reducing costs. For the steel-erection company,

neering and construction challenges. However, inno-

adjacent stadium so the baseball season would be

that meant, nearly every day, receiving and installing

vative thinking and a singular focus on delivering the

uninterrupted.

large pieces of structural steel with tight tolerances.

best-possible result from the entire team brought this

Overall, 880 tons of steel were installed in just the out-

renovation to fruition. The onsite leadership created

field.

an environment that pushed the limits of teamwork to

BLEACHER FABRICATION

The structural design of Wrigley Field's bleachers

optimize methodology and minimize waste of materi-

maintains the historic nature of the ballpark and pre-

SALVAGE AND REUSE

als, time, and effort to generate maximum results.

sented some unique challenges for steel fabrication

Ultimately, there's nothing greener than to preserve

Through a collaborative and best-practice process, the

and erection. The design's connections, column sizes,

and restore an historic building, which is a better use

team transformed a 100-year-old iconic stadium into a

and thicknesses required a complex fabrication, weld-

of resources than a tear down to build a new LEED

ballpark that will provide first-class accommodations

ing, and installation plan, including a 3D model for

facility. Salvage and reuse were a big part of the res-

for generations of fans to enjoy. CA

the fabrication. The bleacher project alone took more

toration. Reuse means less new material was required

than 16,000 labor-hours to complete. It required three

than to build a new ballpark. Some examples include

Dwayne Lindsey is technical services manager with

different production facilities to supply the volume.

salvaging the stadium's existing steel and concrete

Pepper Construction, Chicago. Lindsey has worked in

After analyzing the 3D model, the team confirmed

structure and retaining the outfield brick wall. In ad-

the AEC industry for more than 17 years, specializing

that structural supports could be prefabricated offsite

dition, the ivy was kept covered and alive during con-

in virtual design and construction, and BIM. He may

and installed, essentially, like a large erector set.

struction to avoid being replanted, existing guardrails

be reached at 312-649-7628 or DLindsey@peppercon-

Planning and logistics were critical to keep neigh-

were reused in new assemblies, the exterior fascia was

struction.com. For more information, visit peppercon-

borhood traffic flowing. Each morning during the

reinstalled after the structure was completed, the icon-

struction.com or follow @pepperconstruct on Twitter.

bleacher project, Pepper received confirmation of what
steel members they would receive. Each trip was typically three or four hours so the riggers could plan their
afternoons around what would arrive within a few
hours, depending on the weather.

Sources listed below are linked at commercialarchitecturemagazine.com/1906pepper.

* Watch a time-lapse video of the entire construction process.

* Owners' representative: CAAICON, Denver, caaicon.com

they used as a staging area to store steel members not

* Watch a video about the micropile installation/technology.

yet ready for installation. During the off-season, the

* Architect: Stantec Architecture, Chicago, stantec.com

* Geotechnical Engineer: Hayward Baker, Hanover, MD,
haywardbaker.com

back half of Wrigley Field's Green Lot was also used as

* Architect: Populous, Kansas City, MO, populous.com

* Engineering firm: Thornton Tomasetti, New York City,
thorntontomasetti.com

a staging area for lay-down of arriving materials that

* Contractor: Pepper Const., Chicago, pepperconstruction.com

* Engineering firm: GEI Consultants, Chicago, geiconsultants.com

The steel contractor also had a yard in Chicago that

subcontractors still had to inspect or work on before
20

JUNE 2019

COMMERCI A L A RCHI T EC T UREM AG A ZINE.COM

http://www.pepperconstruction.com http://www.pepperconstruction.com http://www.commercialarchitecturemagazine.com/1906pepper http://www.caaicon.com http://www.haywardbaker.com http://www.stantec.com http://www.populous.com http://www.thorntontomasetti.com http://www.pepperconstruction.com http://www.geiconsultants.com

Commercial Architecture June 2019

Table of Contents for the Digital Edition of Commercial Architecture June 2019