Structural Health Monitoring

1. What is Structural Health Monitoring?

Structures deform as they experience load, resulting in stress developing within the body of the structure. These deformations, and consequently stresses, can be monitored to ensure that they do not exceed specified limits adopted during design, i.e. serviceability limit state and ultimate limit state. CSI offers different Structural Health Monitoring methods to suit the client needs, such as:

• Crack monitoring
  • Especially for RC structures
  • Can be measured manually using a crack ruler or digitally using displacement gauge
• Stress measurement
  • By virtue of strain gauge
  • Stress can then be calculated using known properties of the monitored member or
    in conjunction with the result from material test
• Vibration monitoring
  • Vibration due to service load such as wind, traffic, normal occupancy of the
    structure, as well as probabilistic load such as
    earthquake can be monitored by virtue of an accelerometer
  • Force and deformation can then be estimated from the vibration data

2. When would you use Structural Health Monitoring?

CSI offers flexible timeframes for Structural Health Monitoring; it can be done as a one-off during
test day, continuously for a specific duration (days, weeks, months), or periodically/seasonally for
example to gauge the different environmental effect during summer/winter to the expansion and
contraction of steel railway structure.

3. What are the Benefits of Structural Health Monitoring?

Clients/engineers are most likely concerned if there are cracks in RC floor, beam, column, or wall especially if the structure is relatively new and has only experienced the service load it is designed for. They will want to ensure that these cracks do not widen beyond the limit imposed during design. Other times, an engineer might be interested in the existing stress within old pre-stress elements, such as within a hollow core or flat slab units, to ensure they are sufficient in capacity to support additional loading.

Vibration monitoring is useful for researchers as well as for practicing engineers.