Wireless nano sensors could save bridges, buildings

Apr 09, 2010

Could inexpensive wireless sensors based on nanotechnology be used to alert engineers to problematic cracks and damage to buildings, bridges, and other structures before they become critical? A feasibility study published in the International Journal of Materials and Structural Integrity would suggest so.

Mohamed Saafi of the Department of Engineering and Management, at North Dakota State University, in Fargo, and colleagues at the National Institute of Applied Sciences, in Tunisia, together with a team at the Department of Engineering Technology, at Alabama A&M University, point out that civil structures are prone to continuous and uncontrollable damage processes during their designed service lifespan. These damaging processes might be due to weather, aging of materials, earth tremors, and a lack of maintenance.

A continuous monitoring system is needed to improve safety. Unfortunately, the costs and required time expenditure often mean monitoring is not carried out in a timely manner and trivial problems, such as small cracks and fissures, ultimately become serious conditions that threaten the integrity of a structure. The researchers suggest that nanotechnology and wireless systems could be the answer.

As a proof of concept, the researchers have developed and evaluated two types of wireless devices for the remote monitoring of concrete structures. The devices are sensors based on microelectromechanical systems, MEMS, and were designed to monitor temperature and moisture within the concrete. Long gauge nanotube sensors were employed for crack detection in the feasibility study. MEMS and nanosensors have already been used in a wide range of engineering and science fields such as transportation, communication, military and medicine. Their use in civil engineering is a new application with great potential.

"If designed properly, wireless MEMS and nanotechnology-based sensors could be used as embedded components to form self-sensing concrete structures," the team explains. Such devices would gather and transmit information about the health of a structure by detecting the early formation of tiny cracks and measuring the rate of key parameters, such as temperature, moisture, chloride, acidity and carbon dioxide levels each of which might reflect a decrease in structural integrity.

"Information obtained from such monitoring techniques would allow the owners to make critical decisions regarding operation, maintenance, repair and replacement under financial constraints," the team says.

Explore further: Wireless sensor transmits tumor pressure

More information: "Wireless and embedded nanotechnology-based systems for structural integrity monitoring of civil structures: a feasibility study" in International Journal of Materials and Structural Integrity, 2010, 4, 1-24

add to favorites email to friend print save as pdf

Related Stories

New sensors capable of measuring damage to infrastructure

Jan 05, 2009

(PhysOrg.com) -- Dr. Genda Chen, professor of civil, architectural and environmental engineering at Missouri University of Science and Technology, was recently awarded a patent for "Strain Sensitive Coax Cable Sensors for ...

Study: Wireless sensors limit earthquake damage

Apr 13, 2007

An earthquake engineer at Washington University in St. Louis has successfully performed the first test of wireless sensors in the simulated structural control of a model laboratory building.

Picking up bad vibes to gauge bridge health

May 02, 2007

By monitoring changes in vibrations of bridges it is possible to identify hidden cracks and fractures, according to a Queensland University of Technology researcher.

Recommended for you

Wireless sensor transmits tumor pressure

18 hours ago

The interstitial pressure inside a tumor is often remarkably high compared to normal tissues and is thought to impede the delivery of chemotherapeutic agents as well as decrease the effectiveness of radiation ...

Seeing through the fog (and dust and snow) of war

Sep 19, 2014

Degraded visibility—which encompasses diverse environmental conditions including severe weather, dust kicked up during takeoff and landing and poor visual contrast among different parts of terrain—often ...

The oscillator that could makeover the mechanical watch

Sep 18, 2014

For the first time in 200 years the heart of the mechanical watch has been reinvented, thereby improving precision and autonomy while making the watch completely silent. EPFL researchers have developed an ...

User comments : 0