FAQ#033 – I have received the calibration Report of a piezometer. There is not the K Thermal Factor noted. In which way may I proceed?
If the value is not indicated in the Calibration Report, you should use this formula: K = -1 digit/°C For each degree of increase of temperature you should reduce 1 digit.
FAQ#032 – Which is the reading method of the new generation of SISGEO vibrating wire readouts and loggers?
For VW sensors Sisgeo has developed automatic algorithms to search for the resonant frequency in case of environmental noise or poor signal. In this way you can distinguish between the natural frequency of the sensor and the frequency of the noise, thereby reducing measurement errors and false alarms. This method also provides improvement in the […]
FAQ#031 – Is the DEX system suitable for in-place applications?
DEX system has been designed for automatic soil settlement monitoring (vertical movement) in unattended location. DEX system consists of a string of DEX probes installed in borehole within a ABS inclinometer casing. DEX-S, the combined inclinometer-settlement probe, provides both horizontal movements (X, Y-axis) and vertical settlement (Z-axis) for 3-D borehole automatic profile monitoring.
FAQ#030 – Why do the NATM pressure cells have repressurizing tubes?
NATM pressure cells are normally used to measure tangential and radial stresses in concrete tunnel lining. They are embedded in concrete and after curing the cell shall be repressurized to mantain the intimate contact between the pessure pad and the surrounding material.
FAQ#029 – What is the Real Gauge Factor reported in the Specifications and Compliance Certificates of both VW embedded and arc-weldable strain-gauges?
The gauge factors for VW strain-gauges are generic factors calculated from the dimensions and the physical properties of the gauge material. The VW strain-gauges arep roduced in series with industrial method, so each strain gauge is equal to the other: it means that the gauge factor of VW strain gauges do not change. The Gauge […]
FAQ#028 – Are the vibrating wire strain-gauges and spot weldable VW strain gauges equipped with temperature sensors?
Yes, vibrating wire strain-gauges, as well as all other Sisgeo’s vibrating wire instruments, are equipped with a built-in NTC thermistor YSI 44005 type (3000 Ohm at 25°C). Thermistor is included in the instrument price and therefore there is not additional cost for it.
FAQ#027 – Which type of damping fluid is recommended for filling the pendulum tanks?
We recommend to use the following mineral oil with selected viscosity: SAE 50-90 for direct pendulums SAE-10 for inverted pendulums.
FAQ#026 – What can we do when the inclinometer casing ‚float‘ during installation?
If the water filled casing is lighter than grout backfill the uplift force of grout varies with the height of the grout column. If the column is short, the uplift force is low and the casing can be held in place by its own weight or with very little down-force applied from the top. When […]
FAQ#025 – How get good readings with inclinometer probe?
A good practice for getting good readings with inclinometer probe is to follow these simple operations: – Use the same probe for each survey, if possible; – if you must use a different probe, be sure to note the serial number of the probe used for each survey, so any necessary corrections can be made […]
FAQ#024 – How can we keep efficiently the inclinometer operating cable?
A good practice for the inclinometer users is to follow these simple recommendations: – when you connect the inclinometer operating cable to the probe, avoid overtightening the nut, since this will flatten the O-ring and reduce its effectiveness; – use a pulley assembly. It protects the inclinometer operating cable and provides a good reference index; […]
FAQ#023 – For obtaining best results with inclinometer, must the borehole be very close to the vertical?
Borehole should be drilled as close to the vertical as possible, however 2/3 degrees from vertical are normally accepted in specifications.
FAQ#022 – Why NATM pressure cells have repressurizing tubes?
NATM pressure cells are normally used to measure tangential and radial stresses in concrete tunnel lining. They are embedded in concrete and after curing the cell shall be repressurized to mantain the intimate contact between the pessure pad and the surrounding material.