PURPPOSE OF STRUT STRAIN GAUGE MONITORING
- Determining the deformation values of strut that service during basement excavation.
- On that basic, giving the deformation values of strut under the impact of external force at measured positions.
METHOD OF STRUT STRAIN GAUGE MONITORING
Using vibrating wire strain gauge model 4000 manufactured from Geokon Inc. with the following specifications:
 |
Standard range | 3,000µε |
| Resolution | 1 µε | |
| Accuracy | ±0.1% to ±0.5%FS | |
| Nonlinearity | <0.5%FS | |
| Temp. range | -20 to +80 deg | |
| Length | 150mm |
The strain gauges are attached to the the kingpost and strut by welding two ends with the steel structural at location specified by the Owner. The cable will be connected from the sensor to datalogger (readout box).
The monitoring is conducted at site according to the following steps:
- Connecting signals cable of each sensor with readout data;
- Measuring and recording data at the position of sensor installation;
Allowable deformation is specified by the Owner and Design contractor.
APPLIED STANDARD
- TCVN 9381:2012 “Instructions assess the level danger of construction”.
