Case Study

University of Dayton School of Engineering
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Case Study #5, Rev. 0 Page 1 of 19 15 April 2022
CEE 595 01 (CEM 523) Case Study Number 5: Risk Response Planning
Allegiant Stadium
Figure 1: Allegiant Stadium
“I’m in pro football to win, to have the Raiders dominate, to have the Raiders global, and we’re not going
to be able to do that with a half‐filled stadium.”
Al Davis, late owner of Raiders NFL football team
Project Background: Allegiant Stadium Achieves Earlier‐Than‐Planned Certificate1
The Mortenson | McCarthy design‐build joint venture received a Certificate of Occupancy on Allegiant
Stadium, the new home of the NFL’s Las Vegas Raiders and notably the largest entertainment venue in
Las Vegas, Nevada. The joint venture team wrapped up the $1.97 billion facility on July 30, 2020 marking
the end of a successful 31‐month‐long construction schedule, a mere 40 months after the NFL’s
approval of the Raiders’ move to Las Vegas. With this milestone reached, Allegiant Stadium’s operations
team will move into their new facility to begin preparations for the venue’s first event.
The 1.8 million‐square‐foot stadium will also host UNLV Football and a variety of other sporting and
non‐sporting events. The facility features 65,000 seats, a retractable natural turf field, large operable
walls that open to spectacular views of the Las Vegas Strip, a translucent roof, and a variety of premium
spaces throughout all levels.
1 This section extracted from https://www.mortenson.com/newsroom/allegiant‐stadium‐complete
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As the Design‐Build contractor responsible for Allegiant Stadium’s design and construction, Mortenson |
McCarthy led a team comprised of more than 200 firms, including engineers, subconsultants, trade
contractors, and vendors, and partnered with the Raiders organization, owner’s representative CAA
ICON, designer MANICA Architecture, and the project’s design team which includes architect HNTB, and
engineers Arup, Smith Seckman Reid, Inc., and Kimley Horn.
Visually inspired by the sleek and gradual curves of a futuristic luxury vehicle, Allegiant Stadium is unlike
any other venue, making it an architectural and engineering marvel. The unique features of the domed
stadium include the cable net truss system used for the roof. The seven‐acre ETFE (ethylene
tetrafluoroethylene) roof is suspended by 100 stainless steel cables that create the light‐weight roof
structure diaphragm.
Meeting the challenge to provide the Raiders with a real grass field in the desert, the building also
features a retractable field system. Weighing nearly 20 million pounds, the playing field is housed in a
movable “tray” and moves on 540 electrically‐powered wheels, which allows the natural grass field to
move outdoors for sunlight and water. This feature provides the stadium with both natural grass or turf
playing surfaces. Allegiant Stadium also features a striking memorial, the Al Davis Memorial Torch, which
is among the largest 3D‐printed structures in the world and honors the legacy of the former principal
owner, general manager and head coach of the Raiders.
Figure 2: Al Davis Memorial Torch (Special Feature of Allegiant Stadium)
“Football fans and the community of Las Vegas will really enjoy the design and unique elements of this
stadium,” stated Eric Grenz, Mortenson | McCarthy Vice President of Operations. “Allegiant Stadium is
second‐to‐none and sets a new benchmark for sports and entertainment facilities. We’re thrilled to
reach this important milestone and look forward to seeing the stadium come to life when it opens.”
Design‐Build delivery was instrumental to the project’s success and technology drove enhanced
decision‐making at all facets of the project, ultimately reducing the time and cost of construction.

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Mortenson | McCarthy made worker safety a priority throughout construction and in doing so achieved
a remarkable safety record with a total recordable incident rate (TRIR) of 0.98, which is less than one‐
third the national average. More than 12,000 individuals contributed to the project’s design and
construction.
Figure 2: Aerial View of Construction of Allegiant Stadium
Workforce and business inclusion were at the forefront of building Allegiant Stadium. The project
exceeded all small and diverse business goals, with 23% awarded to small businesses and 62% of the
workforce being minority and female.
From the procurement process to training opportunities and student tours exciting the next generation
of builders, efforts were focused on the Las Vegas local community. 70% of all firms involved on the
project were Nevada‐based companies. More than six million labor hours went in to constructing the
project and an estimated 6,000 recurring jobs will be sustained or created to maintain venue operations.
“To see first‐hand the impact this project has had on every worker, business, intern and visitor has been
extremely humbling,” said Mortenson | McCarthy Project Executive Paul Dudzinski. “This team has
accomplished something incredible together, and we are proud to be able to share this amazing
destination with our neighbors and community.”

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Project Background: Allegiant Stadium Named AGC Build America Award Winner2
The Associated General Contractors of America (AGC) has named Allegiant Stadium as the winner of a
2021 Construction Risk Partners Build America Award, in the Design‐Build Building category.
Construction of the new $2 billion home for the Las Vegas Raiders was completed in July 2020, marking
the end of a successful 31‐month‐long construction schedule, a mere 40 months after the NFL’s
approval of the Raiders’ move to Las Vegas.
As the Design‐Build contractor, Mortenson | McCarthy built a team of more than 200 firms and used
digital modeling from the start to drive performance and maximize efficiency. This delivery model was
critical to the team’s success as they navigated unique design elements and installations, and overcame
challenges working towards a common interest.
The project achieved industry‐leading workforce diversity, exceeded local, small, and women &
minority‐owned business goals, and established a new industry benchmark in sports construction and
for Southern Nevada. It also successfully created long‐lasting opportunities for diverse local businesses
and its more than 12,000‐person craft workforce.
The Build America awards honor AGC members who build the nation’s most impressive construction
projects ranging across the building, highway and transportation, utility infrastructure, and federal and
heavy divisions. A panel of judges representing a cross‐section of the construction industry evaluated all
nominated projects for state‐of‐the‐art advancement, project management, innovation in construction
techniques or materials, safety record, client service, community relations, environmental sensitivity,
and partnering excellence.
Project Background: ENR Project of the Year Finalist and Best Project3
Project Participants:
Owner: Las Vegas Stadium Events Co. LLC
Architect of Record: HNTB
General Contractor (Design‐Build): Mortenson | McCarthy Joint Venture
Civil Engineer: Kimley‐Horn
Structural Engineer: Arup
MEP Engineer: Smith Seckman Reid Inc.
Concept Architech: MANICA Architecture
2 This section extracted from: https://www.mortenson.com/newsroom/allegiant‐stadium‐named‐agc‐build‐
america‐award‐winner
3 This section extracted from: https://www.enr.com/articles/52826‐best‐sports‐entertainment‐project‐of‐the‐
year‐finalist‐allegiant‐stadium

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Construction Manager: CAA ICON
In constructing the Allegiant Stadium project in Las Vegas, the joint venture contractor led a team of
more than 100 firms to complete one of the country’s largest design‐build projects under budget and on
time despite a demanding 32‐month construction schedule in the midst a global pandemic. Hailed as an
architectural and engineering marvel, the 1.75‐million‐sq‐ft, 65,000‐seat domed stadium features one of
the largest‐cable net roofing structures in North America and retractable walls that offer impressive
views of the Las Vegas Strip.
The seven‐acre ethylene tetrafluoroethylene roof is suspended 195‐feet in the air by 100 lightweight
stainless‐steel cables to create an outdoor feel in a temperature‐controlled facility. To erect the 24‐ton
system, contractors spread the 800‐ft cables across the stadium’s lower bowl and hoisted them into
place.
Before they could break ground, contractors needed to relocate a reinforced box culvert to position the
stadium in a location that would provide fans with the best views of the Las Vegas Strip and allow for
full‐sun coverage year round. The joint venture worked with the U.S. Army Corps of Engineers to obtain
environmental and construction permits to make this goal possible.
Crews relied on an onsite concrete batch plant to eliminate logistical or quality concerns. By focusing on
repetition in the building’s eight concrete cores and developing a sequence for multiple crews to work
concurrently, the team increased efficiency and reinforced quality and safety standards.
The Allegiant Stadium project schedule was developed in concert with trade partners and updated
weekly with actual progress reports and fragments resulting from the week’s activities. The 4D model
was updated each month. Engineering consultants concurrently reviewed the model for any quality
damages that might have happened due to Mother Nature at certain points in construction—one firm,
for example, analyzed the model for wind uplift on the structure during roof installation.
This was the first time a cable net roof structure had been constructed in the U.S., so using models and
diagrams provided by trade partners, construction simulations were pivotal in visualizing complexities
never before encountered. To minimize risks for the crane pick of the massive operable doors, the
project team simulated how the doors would be swung into place and then was able to determine the
crane trajectory needed to safely install the operable doors without damage to the primary structure.

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Figure 3: Nighttime Aerial View of Allegiant Stadium
Case Study Background: Considerations When Designing & Constructing Multi‐Purpose Sports
Facilities
4
Just one year removed from Super Bowl LII, all eyes will once again descend upon U.S. Bank Stadium in
Minneapolis, Minnesota as the venue hosts the NCAA men’s basketball championship. The Minnesota
Vikings’ home turf will soon be swapped out for hardwood and courtside seating systems. Transforming
the stadium into a basketball arena is no small feat—the setup process takes nearly three weeks to
complete.
Designing a stadium that is capable of accommodating a variety of sports is certainly not a new concept.
During the building boom of the 1960s and 1970s, the infamous multi‐sport “concrete donuts” were
embraced by cities looking to reap the economic benefits of co‐locating their professional baseball and
football teams. While NFL‐ and MLB‐shared stadiums have since become extinct, the appetite for
flexible, multi‐purpose venues is greater than ever. U.S. Bank Stadium is a prime example.
U.S. Bank Stadium was designed as a “football‐first facility” for its primary tenant, the Minnesota
Vikings. Since NFL games occupy the space no more than 12 times a year, the Minnesota Sports Facilities
Authority has the opportunity to schedule revenue generating events during the other 350‐plus days. In
addition to the Super Bowl and Final Four, U.S. Bank Stadium has hosted a variety of big‐name events,
4 This section is extracted from https://www.mortenson.com/newsroom/next‐gen‐stadium‐considerations , which
is article from Dan Wacker and Erik Thomas. Dan Wacker is a design phase executive and Erik Thomas is a senior
design phase manager in Mortenson’s Sports + Entertainment Group.

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including X‐Games, collegiate baseball, monster truck rallies, concerts, and tradeshows. The facility has
truly become a versatile asset for the State.
The next generation of stadiums are poised to follow this proven approach, combining amenities and
features that cater to the fan experience and have the ability to accommodate bottom line boosting
events and activities. In order to maximize their investment and increase venue flexibility, it is critical for
owners to consider the following elements during the design phase of multi‐purpose stadiums as they
can significantly impact construction and long‐term operating costs:
Seating
Seating types and configurations are driven by the programmatic needs of a stadium. For venues looking
to maximize their versatility, retractable systems enable operators to efficiently scale up or scale down
their seating based on the required floor space. Events with a smaller footprint, such as basketball,
hockey and concerts, necessitate the rental of temporary seating to fill the open floor space and
accommodate larger audiences.
Figure 4: Inside Allegiant Stadium
Circulation
For events such as concerts and basketball, the most expensive tickets are typically for seats located on
the event level rather than the premium spaces. In order to deliver an exceptional experience for these
customers, special consideration must be given to optimizing circulation on the event floor and
providing easy access to amenities. Venues have dealt with these challenges by setting up temporary
restrooms and food and beverage points of sale. Others have found success in allowing these customers
to use club access points and facilities.
Event Level Surface
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Sports and entertainment events often have competing interests when it comes to a stadium’s event
level surface. Sports teams prefer the playability and safety of natural grass, while artificial turf is ideal
for stadiums that host a large number of events that cause more wear and tear like concerts and action
sports. Durable artificial surfaces are less susceptible to damage when covered with field protection
systems for required events, resulting in a longer life expectancy than natural grass. Budget permitting,
stadiums can have the best of both worlds. Allegiant Stadium in Las Vegas will feature an artificial turf
field on the stadium floor for UNLV football as well as a retractable natural grass field tray for Raiders
football. The grass field will be rolled in and out as needed for events, and to allow for year‐round
growth.
Rigging Infrastructure
Rigging requirements for sports and entertainment events, particularly concerts, place substantial
demands on a stadium’s structural system. A collection of trusses, bracing, catwalks and rigging beams
are needed in order to support hundreds of thousands of pounds of video boards, speakers and lighting
equipment. For the Final Four, U.S. Bank Stadium will need to hang a center‐hung scoreboard from the
roof to replicate the authenticity of a collegiate basketball experience. While floor‐based support
systems can be rented for each event, ROI (return on investment) opportunities exist for venues that
incorporate these structural requirements into their original design.
Loading Access
Ease of loading and unloading is of paramount importance to event promoters when booking venues.
Large concert tours travel with upwards of 80 semi‐trucks that require access to the building to deliver
staging, lighting audio and other production equipment. A monster truck show requires 300 dump
trucks full of dirt. In order to expedite crews, determining the ideal number of loading docks and the
most efficient path to the event floor is critical during the planning of a stadium.
Acoustics
Large covered stadiums pose a myriad of acoustical challenges including extreme reverberation, echoes,
distortion and sound absorption. Standard structural building materials such as exposed concrete, steel
and glass exacerbate these issues by adding to the sonic bounce. Venues seeking to host concerts can
benefit from a distributed sound system and acoustic treatments that increase control. U.S. Bank
Stadium, for example, places giant curtains behind the stage for concerts in order to cover the largest
portion of glass on the west side of the facility.
HVAC (Heating Ventilation and Air Conditioning)
Due to the immense size and capacity of their venues, stadium operators are often faced with massive
utility bills. HVAC systems in particular are known for being some of the biggest energy hogs. Innovation
in building design and materials has successfully reduced heating and cooling demands in recent years.
U.S. Bank Stadium is 20 percent more efficient than its predecessor, the Metrodome, due to its ethylene
tetrafluoroethylene (ETFE) roof—a translucent plastic that allows sunlight in, as well as its natural heat.
Stadiums located in warmer climates have chosen to incorporate energy‐efficient glass to keep heat out
and reduce cooling costs.

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While it can be tempting to focus on the first costs associated with building a stadium, it is important to
not lose sight of long‐term goals. When evaluating the desired programming mix for a venue, owners
must consider the capital costs associated with reconfiguring and modifying their stadium for various
events and also ensure the design has the infrastructure required to support their vision.
Project Background: Timetable of Project 5
Listed below are the key events in the life of the Allegiant Stadium project:

July 6, 2015 By executive order, Gov. Brian Sandoval forms the Southern Nevada Tourism
Infrastructure committee to study building an NFL‐caliber football stadium that
UNLV could also use.
The Southern Nevada Tourism Infrastructure Committee delivers its
Sept. 15, 2016

recommendations for building a stadium and how to finance it to Gov. Brian
Sandoval.

Oct. 17, 2016 Gov. Brian Sandoval signs legislation approved in a special legislative session
committing the state to providing $750 million for the NFL stadium project.
The inaugural meeting of the Las Vegas Stadium Authority, which ultimately will
become the owner of the stadium, is held. Steve Hill chairs the new board.
NFL approves the Oakland Raiders’ plan to relocate to Las Vegas and begin play in
2020. Hotels begin collecting room taxes to support stadium bonds.
The Oakland Raiders acquire 62 acres at Interstate 15 and Russell Road for $77.5
million to build an indoor football stadium.
In a stirring ceremony remembering the victims of the Oct. 1 shooting, the Raiders
break ground on the 65,000‐seat stadium.
The Stadium Authority and the Raiders sign off on the final development and lease
agreements for the planned $1.8 billion stadium.
Las Vegas‐based Allegiant Travel Co. is officially announced as the naming‐rights
partner for the stadium that will be known as Allegiant Stadium.
Contractors complete sealing the roof of Allegiant Stadium. Testing continues for
the natural‐grass field tray and north‐end lanai doors.
Contractors meet the deadline for substantial completion of Allegiant Stadium.
Work not essential to staging games and events will continue through October.
Dec. 5, 2016
March 27, 2017
May 1, 2017
Nov. 13, 2017
March 1, 2018
Aug. 5, 2019
April 17, 2020
July 31, 2020

5 Data presented in this section is extracted from https://www.reviewjournal.com/business/stadium/key‐dates‐in‐
the‐evolution‐of‐allegiant‐stadium‐2107342/
or https://populartimelines.com/timeline/Allegiant‐Stadium.
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Sep 21, 2020 First NFL football game played at Allegiant Stadium, when Raiders hosted New
Orleans Saints on Monday Night Football.
The Raiders played their first game at the stadium with fans in attendance, a Week 1
Sep 13, 2021

Monday Night Football matchup against the Baltimore Ravens. The team required
fans entering the stadium to show either proof of COVID‐19 vaccination or receive a
vaccination at the stadium and wear masks.
The following figure provides a timeline of several key events in the life of the Allegiant Stadium project.
Figure 5: Timeline of Key Events for Allegiant Stadium Project
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Project Background: Novel Construction Approaches 6
To build a stadium in less than 3‐years, when a project of this scale would typically take 5‐years, a series
of novel construction approaches were used to improve the project’s construction timespan.
Relocation of Stormwater Drain: As part of the site preparation effort, an existing stormwater drain that
ran across the stadium site had to be diverted. This allowed the project to save substantial time in its
early phases.
Use of Explosives to Prepare the Site: With the site cleared, explosives were used to break‐up tough
ground and excavate the stadium’s bowl; an exercise that saw over 685,000 cubic meters of earth
removed. While part of the new structure sits below ground to keep the interior cool and better
distribute fans on game days, the lower site elevation created by excavation also accommodates the
stadium’s 8,500‐tonne retractable grass field. This will be the main surface that the Raiders play on, but
between games the grass field will slide out of the stadium to reveal an artificial turf surface on the
stadium floor for use by the University of Nevada (UNLV) Football team.
Piling and Concrete: With the excavation complete, some 20 kilometers of piles were driven across the
site to support the building’s superstructure and the stadium’s eight concrete cores began to rise. The
project required over 80,000 cubic meters of concrete to be poured and saw an on‐site plant created to
cope with the demand.
Figure 6: Explosives and Piling Work for Allegiant Stadium7
Waterproofing: The waterproofing project came after the concrete was placed and, according to
Eberhard Southwest Roofing, was arguably the most exciting part of the whole stadium build. The
stadium’s footprint encompasses 650,000 square feet., is 30‐feet deep, and was the first big phase of
the project. The road leading in and out of the stadium had 20 semi‐trucks in an assembly line that were
6 Information in this section is from https://www.theb1m.com/video/las‐vegas‐1‐8bn‐mega‐
stadium?A=WebApp&CCID=22723&Page=2&Items=15
and http://architecturalwest.com/2020/09/23/new‐raiders‐
stadium/
7 Construction photos from Raiders.com website: https://www.raiders.com/photos/photos‐from‐start‐to‐finish‐
the‐building‐of‐allegiant‐stadium‐las‐vegas‐2021

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there to relocate massive amounts of dirt. Eberhard then waterproofed the slab and walls with GCP
peel‐and‐stick Bituthene® membrane before installing 2”‐thick insulation board.
The field is retractable and can either spend time outside, in growing position, or inside, in a playing‐
field position. This movable field tray had to be waterproofed with hot rubberized asphalt on the
bottom for a total of 86,000 square feet. Eberhard used the MM6125® monolithic membrane from
American Hydrotech®, which was topped with 3’ of sand and soil, with impeccably grown grass on top.
“The whole process, from the planning to the execution, was incredibly scientific,” said Paul McKellar,
vice president of Eberhard Southwest Roofing. “The grass has to be perfectly flat and kept green at all
times.”
In addition to the field tray, five different areas of exterior terraces throughout the stadium utilized
American Hydrotech’s MM6125 monolithic membrane, encompassing a total of 80,000 square feet.
Hydroflex® 30, a heavy‐duty, synthetic fiber‐reinforced sheet, was applied on the high‐traffic terraced
areas to provide additional protection. While the field tray was always specified for hot rubber, the
terraces originally called for cold‐applied products. However, Eberhard advocated for a thicker, more
durable option with MM6125. “Hot rubber is far and away the best for this type of horizontal, flat
surface,” explained McKellar. “Here in Southern Nevada, we use American Hydrotech pretty
extensively. We like it because it is thick, self‐healing, and can be used on a variety of projects that have
no slope.”
Stadium Structure and Roof: The structure’s steel frame was then constructed and steadily enclosed
with the black glass curtain wall system. Large sections of the walls were assembled in factory conditions
away from the site, before being transported to Las Vegas and installed. Finally, despite requiring some
re‐engineering, the transparent ETFE roof was fitted; a clever feature that allows natural light but less
heat into the stadium.
Figure 7: Structure Erection of Allegiant Stadium8
8 Construction photos from Raiders.com website: https://www.raiders.com/photos/photos‐from‐start‐to‐finish‐
the‐building‐of‐allegiant‐stadium‐las‐vegas‐2021

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Qualitative Risk Analysis
This case study is derived from actual project information. However, the discussion of risk planning and risk
management for the project has been created by the author of the case study for academic/educational use.
Risk Thresholds
Given the scale of a project that would approach $2 billion, the following risk thresholds (risk scales)
were established for the project.
Probability Scale

Rating Very Low Low Moderate High Very High
Probability <10% 10%‐30% 30%‐60% 60%‐90% >90%

Impact Scale

Project
Objective
Impact Rating
Very Low Low Moderate High Very High
Cost
(all costs in US
dollars)
Less than
$400,000 cost
increase
$400,000 to $1
million cost
increase
$1‐$3 million
cost increase
$3‐$10 million
cost increase
More than $10
million cost
increase
Schedule
(impact to critical
path, in calendar
days)
Less than 7‐day
delay
7–28‐day delay 28–45‐day delay 45–90‐day delay More than 90‐
day delay
Technical:
(Scope)
Scope Barely
Affected
Minor Areas of
Scope Affected
Major Areas of
Scope Affected
Scope
Difference
Unacceptable
Project Scope
is now Useless
Technical:
(Quality)
Quality
Degradation
Barely
Noticeable
Only Very
Demanding
Applications Are
Affected
Quality
Reduction
Requires Owner
Approval
Quality
Reduction
Unacceptable to
Owner
Project is now
useless
Health, Safety Assessment
Required
May add to a
hazard
Creates a
hazard
Potential for
illness, injury or
fatality
Likely to cause
illness, injury or
fatality

Risk Map
Based on the risk tolerance of the Owner (Stadium Authority), Main Tenant (Las Vegas Raiders Football
Team) and Design‐Builder (Mortenson | McCarthy Joint Venture), the following risk map was used to
rank the risks that were identified for the project.

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Figure 8: Risk Map for Allegiant Project
From a risk tolerance perspective, the Owner, Main Tenant and Design‐Builder agreed that construction
activities related to a risk should not start unless the risk map rating was in an acceptable rating area,
which was determined to be the risk map rating of medium or less – that is, risk was in the yellow,
yellow‐green or green zones in the risk map.
Risk Response Discussions
Risk #1: Difficulties During Roof Erection – Structural Element Failures9
Once the concept of Allegiant Stadium was determined, all involved in the project knew that erection of
the stadium’s cable‐net roofing system would be a challenge, as it was the first time this type of roof
had been installed in the US. Ahead of the roofing system’s installation effort, Don Webb, chief
operating officer of the Raiders’ construction subsidiary, said the complexity of the process left little
room for error. The roofing system is comprised of 100 steel cables in a crosshatch pattern — stretching
as long as 800 feet and weighing up to 24 tons — that support a translucent roof of ETFE (fluorine‐based
plastic) roofing panels.
9 Elements of this section is extracted from: https://www.reviewjournal.com/business/stadium/allegiant‐stadiums‐
intricate‐roof‐system‐a‐pain‐in‐the‐neck‐2106688/

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Figure 9: Elements of Cable‐Net Roof System Laying Within Allegiant Stadium
10
The Problem
The risk statement for Risk #1 was: During erection of the cable‐net roofing system, support elements
for the main cables are found to not work as designed due to the large stresses that occur during the
actual lifting, thus causing a delay to the erection campaign while a revised design is determined and
modifications to the support scheme is made.
The probability is assessed to be 65% and worst‐case impact would be a delay to the critical path of 60
calendar days while the design to the support scheme is determined and changes made at the site.
Possible Risk Responses
During the monthly risk review meeting in August 2018, the following risk responses were considered:
1. The Structural Engineer (Arup) could be tasked to lead a series of detailed design reviews and
further technical analysis with erectors to seek to identify structural issues before the work
started in the field and to find remedies to solve the problem before anything was installed in the
field. The thought was that the probability of occurrence could be as low as 25%, if this was done
and that maximum schedule impact would be just 3 weeks (21 calendar days).
2. The Design‐Builder could explore a different lift sequence where the roof network was lifted to
an intermediate height that other work within the seating areas that are below the roof could
commence during the overall time the roof is lifted in place. This approach would provide a
schedule buffer in case the feared roof erection problems materialized. This effort could reduce
10 Photo extracted from Raiders website: https://www.raiders.com/photos/photos‐from‐start‐to‐finish‐the‐
building‐of‐allegiant‐stadium‐las‐vegas‐2021

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the critical path time after the roof was completely lifted in place by as much as 5 weeks (35
calendar days).
Risk #2: Difficulties During Roof Erection – Weather Effects (Wind)
The Problem
The risk statement for Risk #2 was: During erection of the cable‐net roofing system, the frequency of
high winds events increases and causes significantly more interruptions in the lifting effort than what is
currently considered in the project schedule.
Since the lifts are planned for fall 2019, the probability is assessed to be 80% and worst‐case impact
would be a delay to the critical path of 3‐weeks (21 calendar days) when the work is halted due to safety
concerns.
Possible Risk Responses
During the monthly risk review meeting in August 2018, the following risk responses were considered:
1. Adjust the workweek for the cable‐net installation to 7‐day working (versus the current 5‐day
workweek). This could create a schedule buffer of 10 calendar days, which would completely
offset the worst‐case view of the frequency of high winds.
Risk #3: Breakdown of WiFi System During Initial Operations
One of the desired amenities of the new stadium was to have a state‐of‐the‐art WiFi network within the
confines of the stadium that would provide reliable connectivity by all 65,000 fans. The planned
facilities consist of WiFi network equipment from Cisco, an extensive distributed antenna system (DAS),
fiber optic cabling and backbone services from an internet provider. At the time of opening, the system
would contain the latest technology that was available.
The Problem
The risk statement for Risk #3 was: Due to the inability to conduct an appropriately sized stress test of
the WiFi system before the initial use of the stadium, WiFi system performance during initial events is
poor as problems become apparent and fans are disappointed with the event experience, leading to
perceived poor quality and possible lack of reputation to the Raiders football team franchise.
The probability is assessed to be 55% and worst‐case impact could lead to perception that the stadium is
at an unacceptable level of quality.
Possible Risk Responses
During the monthly risk review meeting in August 2018, the following risk responses were considered:
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1. Work with the providers of the WiFi system components to conduct the most extensive FAT
(factory acceptance test) that would lead to higher confidence that there would be limited
problems during initial operations. The view is that the probability that a significant WiFi system
failure could be reduced by 20%.
2. If time allows before the official opening of the stadium, ask 10,000 fans to visit the stadium for
an hour on a weekend and perform the best WiFi test possible. In exchange for their time, the
Raiders can provide them with a limited‐edition, inaugural baseball cap. The view is that the
probability that a significant WiFi system failure could be reduced by 10% with this response.
Risk #4: Fabricated Steel Delays
Once the concrete foundation work was complete, the next key effort was the installation of the steel
superstructure, consisting of fabricated structural steel members.
The Problem
The risk statement for Risk #4 was: Raw material delivery of steel disrupts the fabricator’s schedule,
creating delays to deliveries of fabricated steel members to site.
The probability is assessed to be 50% and worst‐case impact could be 60‐day delay to the critical
structural steel effort.
Possible Risk Responses
During the monthly risk review meeting in August 2018, the following risk responses were considered:
1. Review the current sequence of erection and identify ways to re‐sequence segments of work and
add two (2) additional heavy‐lift cranes to save up to 4‐weeks (28 calendar days) of steel erection
time.
2. Provide a full‐time expeditor to the steel fabricator to work with their staff to seek to reduce the
probability of raw material delays by 20%.
Risk #5: Maintaining Stadium Bowl HVAC Comfort When North Doors Open
The HVAC for the stadium had to be designed for two operating conditions – one when the building is
totally enclosed and another when the north doors are opened to provide an amazing view of the Las
Vegas Strip.
The Problem
The risk statement for Risk #5 was: When an event is held at the stadium and the north doors are
opened, the outdoor conditions create a situation where the HVAC systems does not provide an

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Case Study #5, Rev. 0 Page 18 of 19 15 April 2022
acceptable comfort of the fans in the stadium – leading to a disappointed experience and deterioration
of reputation of the stadium and the Raiders football team.
The probability is assessed to be 40% and worst‐case impact could lead to perception that the stadium is
at an unacceptable level of quality.
Possible Risk Responses
During the monthly risk review meeting in August 2018, the following risk responses were considered:
1. Using the energy model prepared by the MEP engineer, perform more technical analysis to define
the outdoor conditions that will define when the north doors can be opened during stadium
events and still maintain occupant comfort. If done correctly, the view is that the probability of
occurrence of the risk could be as low as 5% (1 in 20 chance).
Case Study #5 Questions
1. Cite three (3) features of the Allegiant Stadium Project that most impresses you.
2. For each of the five (5) risks that are discussed:
a. Plot the risk in the provided Risk Map in its pre‐response view. On the same map, show
the movement of the risk when the possible risk responses are actioned – this is known
as the post‐response view. Use a separate risk map for each risk (as opposed to showing
them all on one map).
b. For each of the possible risk responses, identify the risk response strategy being employed
(escalate, avoid, transfer, accept, mitigate).
c. In the case where there is more than one possible response, provide your view on which
one would be preferred.

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For Academic Use Only
Case Study #5, Rev. 0 Page 19 of 19 15 April 2022
List of Abbreviations in Case Study

AGC
DAS
ETFE
FAT
GCP
HVAC
MLB
Associated General Contractors of America
Distributed Antenna System
Ethylene Tetrafluoroethylene (material for light roofs)
Factory Acceptance Test
GCP Applied Technologies, a construction products technology company
Heating, Ventilation, Air Conditioning
Major League Baseball
NFL
ROI
UNLV
National Football League
Return on Investment (financial metric)
University of Nevada – Las Vegas

*** End of Case Study Narrative ***