Modern structural design philosophies prevent injury, damage and downtime from natural disasters, sabotage and other emergencies.

When disaster strikes—man-made or natural—it’s too late to mitigate. But a proactive approach, including preparedness in the structural building phase, can help save lives and property.

Engineers Leslie Duffy and Shaun Walters explain why operators must anticipate events such as terrorism and earthquakes and build to withstand them.

Q&A: Seismic Design

Casino Style: Building codes require a structural engineer to account for earthquakes. What does that process look like?

Shaun Walters: The typical approach for earthquake design essentially takes the ground acceleration that could occur at a site during an earthquake, multiplies that value by the building weight, then divides by a factor between three and eight.

Whether you get to use three, eight or something in between is based on the material and the lateral system (shear wall, braced frame, moment frame). There are other factors that can further modify the primary force you design for, but it’s that simple, and this has been the approach since the late ’70s.

That approach seems too simple to quantify the amount of damage a building may suffer after an event. What kind of damage would we expect after a major earthquake?

The approach is too simple to predict damage with any level of accuracy. The goal of the code for most gaming facilities would fall under a “life safe” performance objective after a major earthquake.

Per the design standards, a “life safe” performance objective is defined as: “Structural and nonstructural damage is significant. The building may lose a substantial amount of its pre-earthquake lateral strength and stiffness, but the gravity-loadbearing elements function… Many architectural, mechanical and electrical systems are damaged. The building may not be safe for continued occupancy until repairs are done. Repair of the structure is feasible, but it may not be economically attractive to do so.”

To summarize, in a significant earthquake your building may not be functioning or permitted to be occupied if designed following traditional code approaches.

It’s rational to design a building to allow occupants to safely exit during a rare event. But is this the performance most developers and owners expect after investing a half-billion dollars or more in a new facility?

I agree that this communication gap between owners and engineers has been a source of discussion in our profession for many years.

Engineers are under pressure to provide low fees, satisfy the minimum code objective and turn around plans quickly. If we tell an owner that we can provide a high-performance design but it’s going to take more time and money, it can be a tough sell if our entire industry is not consistent with the messaging.

We’re also careful not to overstep our role on a project and show up to the project kickoff and start laying on a sales pitch to the owner without consideration of our architectural clients and the owners’ representatives, who have already solidified design schedules and design fees.

Performance-based design is another design approach permitted by the building codes. What is it, and why should a casino resort developer or owner consider it?

Instead of dividing by some factors and multiplying by others in the hope of providing a design that will allow occupants to egress safely, engineers are implementing advanced modeling software to build virtual building models, then subject those to earthquake simulations that are consistent with the type and magnitude that may occur at the specific building site.

We’re then able to design to a specific performance objective (damage goal), rather than a “wait-and-see” approach. For example, if the objective is for a casino to be fully functional after an earthquake that has a 10 percent chance of occurrence in 50 years, we’ll design with that specific target in mind (think hospital, fire/police station, hazardous facility).

If you want operational but not fully functional, then we can target this. If your plan is to build a new facility within 20 years, then reducing material cost and accepting more damage might be the most practical approach.

As engineers, we want the safest design possible, but we understand there are many variables to consider. A modern commercial jet has two engines, but could land safely with one. Obviously, if it had four engines (like Air Force One) and can land with one, that would increase safety through redundancy. But some amount of risk is accepted to keep costs for the consumer and profits for the business in balance.

Another way to think about what can be offered here is, your casino is Air Force One and needs four engines. Maybe your hotel can be renovated while your casino is operational, so give it two engines. And your spa building or auxiliary structures contain fewer people, have a shorter path to safely exit and produce less revenue, so they can have a single engine.

If handed a menu with options, all building owners would choose a fully functional facility after an earthquake. But as with anything, there must be a cost associated with a premium product.

It depends on the situation, and in some cases, construction costs will be reduced because you’re focusing on adding material to the design and building in a much more thoughtful manner.

The code approach tends to throw material everywhere to offset the oversimplified design approach we discussed earlier. The variable material goes into the earthquake-resisting system of the structure, the balance of your structure is not impacted.

For example, the earthquake-resisting elements compromise only a small portion of the structure, so the impact to the overall construction cost may only be on the order of 0.2 percent to 0.3 percent.

The structural design is significantly more intensive, and the design fee may increase by 10 percent to 20 percent. But these amounts are almost negligible compared to the construction cost, increase in building performance and potential insurance premium reductions.

What steps should an owner take to implement these strategies on their project?

If it’s a new project, then communicate to your representative that you’re interested in implementing these design approaches. They can include this in the request-for-proposal to ensure you obtain qualifications from engineering firms experienced in this type of design.

If it’s an existing facility, you can solicit an engineer directly to obtain studies and work alongside your facilities team. For a new project, the goal is to obtain information early enough to make an informed decision on the direction of the design. For an existing structure, it’s to understand how your current facility will perform to determine if an action is necessary.

Q&A: Protective Design

What is “protective design” and how does it work?

Leslie Duffy: Protective design refers to physical design features that are intended to protect people, property or assets, often related to anti-terrorism.

It can mean structural hardening for loads caused by an explosion (blast engineering), site planning to create a boundary to prevent intentional or accidental vehicle ramming scenarios, or space planning to limit the effects of an armed attack.

Traditionally, protective measures were utilized for government buildings. However, these days the targets of terrorism have been more towards mass-casualty events. The point is to create maximum impact to society. So they target areas that draw crowds, or iconic buildings that will generate heavy media coverage.

You likely haven’t heard of protective design, because it’s not something that’s covered in typical building codes. Design of private facilities must consider the specific risk and vulnerability associated with that building or space. While not a code requirement, it would be prudent to consider implementing some aspects of protective design on any high-profile project.

Without criteria, how do you decide what protective measures are implemented on a project?

Where there’s no set requirement, it’s important to assess the risk associated with the facility. We’ll often meet with stakeholders and security personnel to review past events at similar facilities and understand which threats are applicable. Once we have an idea of what we’re trying to protect, we can narrow in on what protective measures should be implemented.

Can these measures be applied to both new and existing facilities?

Absolutely. It’s beneficial to be involved in early planning stages for a new facility so the site or interior spaces can be oriented to maximize protection and limit costs.

With existing facilities, the approach may be geared towards understanding how much protection the existing facility provides. A vulnerability assessment is often performed. where we evaluate how the facility responds under an imposed threat, be it blast or otherwise.

What types of facilities implement protective design? Who are your typical clients?

Our clients are typically 50/50 government and private. We have several social media projects, airports, high-profile schools, stadiums or other iconic structures. We typically work with a design team under the architect but can also work directly for the owner.

Speaking of architects and owners, how do these designs interact with architecture? Are the construction costs associated with implementing these designs increased significantly?

Enhanced security can often make people assume that the structure and site should feel “prison-like,” but there are several ways to increase protection while blending in with the architectural design and remaining cost-effective.

For example, the use of laminated glass on a structure can significantly increase the protection from flying debris resulting from a blast or ballistic event. It’s relatively low-cost and has no effect on the building aesthetic. It’s about finding the right balance between protection and cost.

What’s your take on the 2025 Las Vegas Cybertruck explosion?

Based on my understanding of the event, it was unclear whether the explosion was a terrorist plot or intended to make a political statement. It shows how easy it can be to access the main entry of a populated area and the benefit of avoiding occupied space over a drop-off area.

Further, it shows how technology allows a lone-wolf adversary to easily obtain access to information and plan an attack.

Is this the type of event that you’d expect to be most common in the gaming industry?

The intent of an aggressor is typically to impact the maximum number of people. Threats facing the gaming industry are likely vehicles ramming into lobbies with large groups of people and armed attacks on the gaming floor.

Building design should utilize strategic placement of interior spaces combined with forced entry and ballistics at critical spaces. Implementation of blast resistance is not something I’d typically recommend unless the facility was extremely high profile.