Shake, Rattle, & Roll
Designing for Earthquakes in the West
Earthquakes can be absolutely devastating to the structural integrity of a home or building. Throughout history, seismic events have crumbled whole cities, from Asia to America and beyond. While some areas of the world are more prone to experiencing earthquakes, no geographic location is safe from the potential of cataclysmic tremors. Thankfully, science and design have kept pace with the need for more earthquake-resilient buildings, and there are key considerations to help ensure structures can withstand seismic forces. These considerations include material choice, framework design, shock absorption, and more.
A flexible foundation is ultimately key, and construction design professionals can choose between a variety of options. For example, pads that separate the building from the ground can help mitigate structural movement. Reinforced concrete on top of a cushioned base is another option, as well as a rubber foundation. These base isolators act as shock absorbers, letting the building slide back and forth without incurring damage to beams and joints.
Apple’s headquarters in Cupertino, California, is located smack dab in the middle of earthquake country. Known affectionately as the Spaceship, the building sprawls across 176 acres and is incredibly futuristic. What makes it possibly the most technologically advanced building in the world, however, might be its earthquake-resilient design. Engineered to reduce earthquake shaking by as much as 80%, the building uses a technology called base isolation. The building sits on 692 gigantic stainless-steel saucers, and the building slides on these saucers as much as 4’ in each direction during a seismic event. Inspired by Japanese structural engineering practices, Apple’s headquarters is in a more advantageous position than its neighboring buildings in Silicon Valley when it comes to surviving the destruction of an earthquake.
Seismic events are natural phenomena, and try as we might, we simply cannot completely prepare for them. There are many variables in an earthquake scenario, including the strength of the tremors, as well as the age and integrity of the structures involved. It’s important for everyone to understand the ways in which buildings, and people, can be saved from seismic destruction.
Marcus Dodson
editor & publisher