Fire Sprinkler System: Seismic Calculations & Analysis

How do seismic calculations and analysis factor into a fire sprinkler system design? Fire sprinklers can be life saving installations in case there is a fire outbreak. Conventionally, technicians tend to design the fire sprinkler system in correspondence to the building’s design. However, there are many other things that they have to consider when installing the piping system. Each facility carries its personal fire hazards. Thus, the fire sprinkler system design includes variables including fire risks, building material, size, scale, and environmental threats such as earthquakes.

Fire Sprinkler System Seismic Design

Some buildings or facilities are in locations that possess earthquake threats. The construction of such places requires a seismic design for most of their infrastructure. It must ensure to withstand the seismic tremors of an earthquake, preventing the building from collapsing in case of an earthquake.

In areas vulnerable to earthquakes, constructors also have to make sure that non structural elements are also earthquake proof. These elements include all the mechanical workings in a building, including plumbing systems, electrical wiring, and, most importantly, fire sprinkler systems.

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Importance of Seismic Design of Fire Sprinklers

During an earthquake, the likelihood of a fire outbreak increases. Thus, if a fire sprinkler system fails to work in that instance, this could potentially lead to many deaths. The serious life threatening risk of earthquake-induced fires makes seismic resistance of a fire prevention system crucial. Looking back at the history of natural disasters, it is quite evident that earthquakes pose a great fire threat.

Fire outbreaks do not only put hundreds of lives at risk but also cause financial damage to property owners. Even the slightest of tremors will cause fire sprinkler systems to leak if their design is not compatible and durable to withstand earthquakes. Ultimately, not having a seismic-proof fire sprinkler system will cost you more in damage expenses and rebuilding costs than the initial installation costs. The costly labor and equipment requirements to rebuild a fire sprinkler system may also convince an owner to abandon the facility altogether.

Fires become a likely occurrence during and after an earthquake because of many reasons. The most common one involves the damage to wirings and gas pipes. Even the smallest of electrical sparks can burst into a flame under a gas leak. Other times the earthquake tremors cause fuel spills that increase the probability of fires. In these circumstances, functioning fire sprinklers prove to be pivotal.

Seismic Fire Sprinkler Design

Fire sprinkler systems built to withstand earthquakes require a different design and planning in terms of installation. Technicians implement certain techniques to the water pipes so that they have flexibility and clearance. This allows them to stay intact and function during earthquake tremors.

The foundation of the building, along with beams and columns, tends to shake in different dimensions and speeds. This differential movement phenomenon can damage a conventional fire sprinkler pipe, causing breakage and leakage. Since the fire sprinkler systems run across the ceilings and sidewalls of the building, any horizontal and vertical displacement results in the slamming of walls against the pipes.

To prevent this from happening, technicians install flexible pipe couplings to the sprinkler pipes. This non structural element can bend in correspondence with the structure walls. Hence, you can reduce significant damage in the occurrence of an earthquake by installing these pipes. Moreover, the couplings help mitigate the pressure on the pipes due to differential movement.

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The addition of flexible couplings is just one of the seismic design measures, along with others. Another method of pipe protection takes shape in the form of seismic bracing. This includes the installation of cable sway braces.

Cable Sway Braces

You can also refer to these Sway braces as transverse sway braces. The design specifications for these sway cables require technical analysis of a facility’s design. Hence, technicians need to be wary of the seismic load calculation for the proper installation of the sway cables.

The seismic wave intensity and directional pathways vary greatly according to the location of the facility. They need to consider whether the seismic waves will take the form of “S” waves or “p” waves. This helps them with the placement of the sway cables. To accomplish a successful installation, you will have to consult a qualified engineer who understands the complexity of the seismic load.

Ultimately, sway cables help reduce the stress on the fire sprinkler system during a seismic episode. To ensure that they perform this function, the technician calculates the seismic measure of force using mathematical formulas. Calculation and analysis for seismic damage prevention is a technical burden for only the best fire sprinkler services.

Fire Sprinkler system Seismic Design: Conclusion

Fire sprinkler systems must include seismic design & calculations to protect against natural disasters such as  earthquakes. Only certified professionals with years of fire protection system design experience can create these detailed plans that include these calculations. 

With over 20 years in the fire protection system business, F2M Fire & Drafting Designs Inc. designs efficient and lasting fire sprinkler systems. Along with estimating services, F2M’s owner is one of the most experienced technicians in the industry.

For a free professional consultation online or in person, contact us at (718) 928-3009, or visit our website for more information.