The U.S. Department of Homeland Security (DHS), Washington, D.C., was created after the attacks of Sept. 11, 2001, to keep our nation safe from all types of natural and manmade threats. As part of its efforts, the DHS Science and Technology Directorate (S&T) Resilient Systems Division (RSD), working with the National Institute of Building Sciences (NIBS), Washington, and other organizations, develops infrastructure- and disaster-management programs and tools for use by the public and private sector.
A primary interest of DHS S&T RSD and NIBS is building resilience. DHS defines resilience as the ability to resist, absorb, recover from, or successfully adapt to adversity or a change in conditions. Roger Grant is program director for NIBS’ Integrated Resilient Design Program, which fosters innovative approaches to the design, construction, and operation of buildings and infrastructure to make them resilient to natural and manmade disasters. NIBS’ projects for DHS S&T RSD bring together leading experts in building and infrastructure performance to develop tools and resources so owners, designers and others can integrate resilience into their new and existing facilities to reduce the impact of a disruptive event and the duration of its effects.
retrofit had the opportunity to speak with Grant about NIBS’ work and how the institute is mitigating the risks our buildings face from of all types of natural and manmade disasters.
retrofit: In light of recent tornadoes in Oklahoma and Superstorm Sandy, are we building weak structures?
Grant: We can see examples of buildings that have not been built sufficiently to withstand disastrous events. Even structures that have been built in the last five or 10 years may not be sufficient to withstand the high wind loads and flooding/surge of recent extreme events.
We build to code in our country. We have a great set of building codes in the United States, but their main purpose is to protect the life safety of the people in the buildings—to get them evacuated safely. Codes aren’t necessarily created to ensure the building remains usable after a disaster. Generally, for a building to be strong enough to withstand a blast, high wind, or extensive flooding and then return to operation more quickly, it would need to perform at levels above what the building codes would establish as the minimum for life safety.
r: To make a building more resilient, do we need innovative new materials or can traditional materials be used in more thoughtful ways?
Grant: We’re talking first about how the building is designed. If you’re in an area prone to flooding, you probably need to elevate the building or at least its critical systems. That isn’t necessarily using different materials; it’s more about how the building was designed in the first place. Then, you’re using conventional materials in an appropriate way—maybe you’re using materials that can withstand being immersed in water and can resist higher winds.
However, there is also movement toward new materials. For example, there has been quite a bit of work in glass technology to make it more resistant to high forces. There’s also work in the area of ultra-high-performance concrete that is very lightweight, has very high strength and can be used in many different configurations.