Tilt Monitoring

Construction Tilt Monitoring system & Meter in Singapore.A tiltmeter is a sensitive inclinometer designed to measure very small changes from the vertical level, either on the ground or in structures.Tiltmeters are used extensively for monitoring volcanoes, the response of dams to filling, the small movements of potential landslides, the orientation and volume of hydraulic fractures, and the response of structures to various influences such as loading and foundation settlement. Tiltmeters may be purely mechanical or incorporate vibrating-wire or electrolytic sensors for electronic measurement. A sensitive instrument can detect changes of as little as one arc second.

The main advantages of the portable tilt meter systems are the following:-

  • The manner of installation of the tilt plates is very simple and may be screwed or bonded to the structure.
  • One tilt meter may be used to monitor many bronze tilt plates.
  • The tilt plate is made of bronze which is rugged in construction and has excellent temperature stability.

The portable tilt meter is suitable for monitoring change in inclination of a structure. Tilt meter consists of a basic sensor housed in a rugged frame with machined surfaces that facilitate accurate positioning on the tilt plate. The bottom surface is used with horizontally mounted tilt plates and the side surfaces are used with vertically-mounted tilt plates.

Application & Operation:

When monitoring the movement of buildings, bridges and other structures, one of the most requested measurements is tilt or inclination, to monitor any long-term leaning movements of the structure. This is actually one of the most difficult parameters to measure using proprietary instrumentation as we are trying to monitor the movement of a static structure which is designed NOT to move, hence the signals can be extremelysmall.

The tiltmeter system includes a tilt plate, the portable tiltmeter, and a readout unit. Tilt plates are available in ceramic or bronze. Both types are dimensionally stable and weather resistant. Tilt plates are mounted on the structure in specified locations. They are typically bonded to the structure but may also be screwed to the surface.

To obtain tilt readings, the operator first connects the tiltmeter to the readout unit, then the tiltmeter on the tilt plate. The operator subsequently records the displayed reading. Thereafter, operator rotates the tiltmeter 180 degrees and obtains a second reading. Finally, the two readings are averaged to cancel sensor offset. Changes in tilt are found by comparing the current reading to the initial reading.

QSAFE using GEOKON Model 6101D MEMS DigitalTiltmeter for the measurement of inclinations is essential for the control and security of the civil structures in elevation during the construction phase and in operation.
MEMS tilt meters monitor tilt changes in either one or two axial planes perpendicular to the surface of the base plate.
MEMS tilt meters are permanently installed to provide long term observation and are designed for manual readings.

Application:

  • Bridges and piers
  • Historical buildings
  • Concrete dams
  • Structural load testing
  • Landslide monitoring
  • Building safety along adjacent excavations
  • Berms in open pit mines
  • Retaining walls
  • Ground subsidence

Features

  • Vertical and horizontal
  • Uniaxial and biaxial versions
  • Easy to install
  • High performances
  • Negligible dependence to the thermal factors
  • Long-term stability
  • High dynamic range
  • Precision and durability
  • Small dimensions and low visual impact

Measurement Principle

The Tiltmeter is constituted of two single-axis MEMS sensors (Micro-Electro-Mechanical-System). The sensitivity, reliability and robustness of the sensor, make this instrument an aid for systems which are monitoring deformation of structures and rotation and tilt variations. Installation is simple and immediate, fixed to the wall or ground with the aid of 3 Fixture fixings and a simple initial check with an optical level. Adjustment and refinement plates are available for special applications. Usually, systems with multiple sensors are produced, the sensors being either separate from each other or interconnected by extension bars to allow the formation of chains for monitoring subsidence and structural deformation. Instrument chains allow the monitoring of an entire profile (rather than single points) and provide greater overall accuracy of measurement.