Understanding Acoustic Emission Testing- Reading 1 Part B-A

■ Bridges
Bridges contain many welds, joints and connections, and a combination of
load and environmental factors heavily influence damage mechanisms such
as fatigue cracking and metal thinning due to corrosion. Bridges receive a
visual inspection about every two years and when damage is detected, the
bridge is either shut down, its weight capacity is lowered, or it is singled out
for more frequent monitoring. Acoustic Emission is increasingly being used
for bridge monitoring applications because it can continuously gather data
and detect changes that may be due to damage without requiring lane
closures or bridge shutdown. In fact, traffic flow is commonly used to load or
stress the bridge for the AE testing.
Charlie Chong/ Fion Zhang