The proliferation of data center construction faces many challenges. Power, cooling, security and space are just some of the variables that can make positioning and building a new data center challenging. However, in parts of the world, data center operators are running into new challenges – namely those posed by the impact of earthquakes and frequent seismic activity.
Significant portions of major developed economies such as the US, Japan, Italy, even the UK, experience regular seismic activity. Organizations constructing new data centers and maintaining existing ones are having to think in new ways about how to protect these vital facilities – which do not respond well to violent shaking – from unexpected and unpredictable seismic force. Major economic markets such as California in the US, Tokyo in Japan and Rome in Italy, all exist in areas pre-disposed to seismic activity of varying degrees.
Construction techniques have evolved to make buildings more resilient to earthquake forces, using materials that allow buildings to flex and sway, while a variety of foundation options allow buildings to shift and dissipate shocks. Those advances have traditionally been focused on keeping a building intact and human occupants safe – which can withstand a degree of vibration and shaking – rather than protecting delicate electronics.
Building a data center in an area where earthquake or tremor risk is elevated requires different construction approaches. Ones that will not only keep the building together, the occupants safe, but also allow racks upon racks of servers to survive and remain functional.
Understanding a quake
An earthquake is a sudden shaking or trembling vibrations of the ground produced in the Earth’s crust. This occurs when plates in which elastic strain has been building up suddenly move and then rebound. The vibrations can range from barely noticeable to catastrophically destructive, where the surface of the Earth can be altered by thrusting up cliffs or opening great cracks in the ground. Moreover, this activity can manifest at sea as well as on land, creating anomalies such as tsunamis.
When we were looking at locations to build a new data center in Japan, we had to consider all these options, as well as thinking about how we physically constructed the building.
We already had one data center, located in Inzai City, in Chiba prefecture, about 30 kilometers outside of Tokyo. Given the importance of Tokyo as a global economic base, being in close enough proximity to serve customers and users in the city and its suburbs was important. Inzai provided a good balance, close enough to service the Tokyo area, but far enough away from the city center to also serve as an alternate location for those wanting redundancy. The existing data center also served as a way of understanding the potential seismic forces that a data center would face there, allowing any new data center to be more refined and more resilient.
The tried and trusted way to make a structure more resistant to the lateral forces of an earthquake is to tie the walls, floor, roof together to form a Super Structure. Then have an isolated foundation that becomes the Sub Structure. That is the basic premise for our latest data center. However, in order to nullify the vibrations and keep the equipment as safe as the human inhabitants, we also needed to look at what the building sits on.
Inzai 2 employs the latest in construction techniques to nullify and dissipate the effects of any seismic activity in the region. The super structure sits on a series of Seismic Isolators and Teflon Sliders. These isolators are sometimes called a Shake Table – capable of holding 125 tons per m2, isolating the whole building from any seismic forces and allowing the Sub Structure and Super Structure to move independently. Thus, permitting the bulk of the seismic shock/energy to be dissipated by the Sub Structure and reduce the impact on the Super Structure.
The seismic isolator base effectively allows the upper section of the building to float, rather than directly connecting it to the moving ground. The result is a substantial reduction in the impact of any movement, and a considerable reduction in the vibration from a seismic event, protecting the building, customer hardware and staff on-site. By reducing this impact, hard drives are less likely to be damaged or produce write errors, while blade servers and other cards, as well as fans and other cooling aides, are less likely to be unseated by a tremor.
With Inzai 2, we’ve invested in resilience, reliability and in scalability to ensure long-term reliability and data protection. With a result that we achieved a Probable Maximum Loss (PML) of under 3 percent in this data center.
While Japan is a country that is prone to seismic activity across its entire land mass, the Inzai location is ideally suited to data center facilities. This is due to its location above sea level and inset from the ocean, as well as its proximity to major populated areas such as Tokyo and Narita airport, the international gateway to Japan. The positioning minimizes the external environmental risks such as seismic-activated tsunami or a water source such as the Tone River breaking its banks under strain from a tsunami or tremor.
Just one of many considerations
It is worth noting that while seismic activity is a concern for anyone building a new data center, it is just one of many considerations when ensuring a site is as protected and made resilient as possible. Geophysical considerations sit side by side with everything from “is the site on a flight path” to “can the local substation provide enough mains power to run the site at 100 percent”.
According to the World Risk Report, compiled by the United Nations University for Environment and Human Security (UNU-EHS), Japan is the 15th most susceptible country when it comes to earthquakes. As such, the country is a leader in construction innovation to mitigate the impact of unpredictable, variable tremors on buildings. The construction approach for Inzai 2 serves as a useful roadmap not only for data centers in other locations at risk of earthquakes, but also for a variety of modern and tech-centric buildings.
Ian Dixon is vice president of operations at Colt DCS