Every year, Americans spend billions of dollars on routine and preventative medical exams and tests in order to maintain healthy bodies.
Millions of lives are saved because of this routine health monitoring. But we also can save lives by monitoring the health of our nation’s buildings, bridges and many other types of structures.
As medicine and health care have advanced significantly over the past century, so too has the way we design and construct our structures. New construction techniques, building materials, analysis programs and similar technological advancements all have helped engineers and architects push the limits of what our structures can do and what they look like.
Yet, our advancements in structural design and construction have not been enough to prevent structures from failing.
And while the causes of failure are varied, in most cases there are warning signs that a structure’s health is failing. Just as routine medical exams are used to detect these warning signs in our health, there are ways to monitor and detect signs of impending failure in our structures, as well.
Until recent years, the most common methods of failure detection were visual inspection and nondestructive and/or destructive testing. While these techniques are an important part of any structural health monitoring program, their effectiveness is limited. They do not provide context for the state of a structure’s health, nor do they allow for continuous monitoring of a structure’s performance. They also are more prone to human error.
With advanced measuring devices, such as accelerometers, engineers now are able collect data that can be used to assess a structure’s health in real time. Sensors providing up-to-the-minute data provide a far superior assessment of how a structure is holding up.
It is particularly beneficial to infrastructure that is critical, aging or has unique loading conditions.
For critical infrastructure — such as hospitals, power plants, and high capacity bridges — safe and continuous operation is imperative. Health monitoring for these structures should be continuous to ensure early detection of any changes in performance.
Structures with unique loading conditions, such as those in high seismic or hurricane-prone areas, can use real-time monitoring to identify damage and ensure continued safe performance in times of concern.
Even for aging noncritical infrastructure, real-time data can improve on more traditional monitoring techniques and result in better predictions of a structure’s remaining service life.
We are often too quick to replace structures instead of ascertaining their true remaining usefulness.
In each of these cases, structural health monitoring mitigates failure but also aids in the allocation of maintenance spending.
Investing in a proper monitoring program can allow property owners to make more informed decisions about the health of their assets. These assets go beyond structures to include roads, sewers and pipelines, to name a few. Failure of any of these can lead to losses, including loss of life and loss of the structure’s productive or economic usefulness.
As structural health monitoring becomes more prevalent, we will see an improvement in the health of our nation’s infrastructure, leading to lasting benefits to our lives and economy.
Scott Ginal is structures manager at R.A. Smith National Inc., Brookfield.