Visual inspection tells you something has changed. It rarely tells you by how much, or how fast. Repeat scanning does both, across the entire structure rather than at the points someone thought to instrument.
Baseline, then compare
The first capture is the baseline. Every subsequent capture is registered to the same control and differenced against it. The output is a colour map of the structure where deviation is the colour scale — settlement, deflection, scour, spalling and section loss all show up in the same view.
Where it earns its cost
- Quay walls and marine structures — movement and scour tracked between inspections, above and below the waterline where accessible
- Retaining structures and slopes — measured displacement instead of inferred risk
- Tanks and silos — shell deformation and out-of-roundness over time
- Bridges and roads — deflection and pavement condition, whole-asset
Proactive, not reactive
The value is in the trend. Three captures over eighteen months tell you whether movement is settling into equilibrium or accelerating — which is the question that determines whether you intervene now or budget for it later.