All costs are in New Zealand Dollars and exclude GST. They are given as estimates only. They are subject to change due to exchange rates, supplier price and freight price changes.
Structural monitoring of building up to 5 stories tall:
1. Basic system
2 x GMS recorders, one with triaxial sensor and one with biaxial sensor at ground level and roof level
1 x uniaxial accelerometer on rooftop, opposite corner to measure rotation
Analysis software
GPS synchronisation
Direct or ethernet connection
Installation and cabling
Approx. cost NZD $30K-35K including all the items above (depends on cable lengths and final configuration)
2. Add additional acceleration sensors in areas of highest risk and interest Add cost of additional sensors plus cabling. GMS recorder NZD $10,000-13,000; Uniaxial accelerometer NZD $3500 each
3. Add wireless communication between sensors Add NZD $950 per unit, but reduce cost of cabling (may not be feasible at all sites)
4. For more detailed requirements in a larger structure or building, an array of sensors, placed in suitable locations throughout the structure will allow a more complete analysis, including modal and resonant frequency issues. Total cost NZD 160K plus
This type of analysis (generally performed in specialized software such as ARTeMIS) will provide detailed information about the reaction of a structure during minor events as well. These subtle changes to resonance and vibration modes will signal changes in a structure that may not be visible, and can be important indicators of unseen dangers, and requirements for further inspection.
5. Add other structural sensors to measure effect of vibration or movement on structural elements
It is also worthwhile considering monitoring displacement, or strain parameters at critical locations in the structure. For example a measurement of displacement across an existing crack or of strain on structural elements may provide useful data.
Approximate sensor costs (depending on exchange rates and models): Strain gauges: NZD $200-$300 each plus cable Crack meters: NZD $600-$1000 each plus cable Tilt meters: NZD $1000-$1400 each plus cable Load cells: NZD $1200-$1600 each plus cable
Add approx. NZD $6000 for base datalogging unit and configuration, plus sensor cost (see approx. costs below)
