Deformation monitoring
Under deformation monitoring is the systematic measurement and long-term monitoring of changes in the shape or dimensions of an object.
These data are captured and recorded, which are used for further calculations, deformation analysis, predictive and preventive maintenance and messages when crossing predefined thresholds.
The deformation monitoring refers primarily to the field of applied measurement and is used mainly in construction projects, in machine and plant engineering as well as in soil and rock mechanics.
The reasons for the necessary use of a deformation monitoring are changes such as shifts of the substrate, decreasing or increasing strain, change in material properties or external influences.
The next measurement instruments used ( 1) for the deformation monitoring will depend on the application (2), the chosen method (3 ) and the required system (4).
Measuring instruments
The measuring instruments (or sensors) can be divided into two groups, the Geodetic and geotechnical sensors. In a modern monitoring system, both groups can be seamlessly combined.
- Geodetic measurement sensors capture geo-referenced possible displacements or movements in position and / or height. In addition, instruments such as total stations, Levels and receiver for global navigation satellite systems (GNSS ) are used.
- Geotechnical measuring sensors detect displacements or movements are not georeferenced, but measure physical properties. These sensors include extensometers, piezometers, rain gauges, thermometers, barometers, electronic scales hose, inclinometers, accelerometers, seismometers, etc. For more information, see Geotechnical sensors.
- Other measuring sensors such as Radar devices.
Application
Deformation monitoring can be used for detecting movements in the following objects:
- Reservoirs and dams
- Tunnel
- Bridges and overpasses
- Tall buildings and historic buildings
- Foundations
- Construction sites
- Mining and mines
- Slopes and volcanic slopes
- Settlement areas
- Earthquake areas
Method
A deformation monitoring can be carried out manually or automatically.
- With a manual deformation monitoring instruments or sensors manually, ie at irregular intervals and usually without permanent installation used (eg for simple evidence).
- An automated deformation monitoring consists of a set of interactive, continuous or independent software and hardware components that form a complex for deformation monitoring in its entirety. Once the necessary components are installed and prepared for real-time data acquisition and transmission, no further intervention of people is necessary.
In this definition, the deformation analysis and interpretation is not based on the data collected by the monitoring system. This is the task of the deformation analysis software. An automated monitoring system is usually permanently installed, especially when objects are to be monitored continuously or in certain cycles.
Systematics and scheduling
The systematics and scheduling depends on the monitored object and the application. Objects can be fast, high frequency, slowly and gradually move or change. For example, swinging a bridge due to wind and traffic, it can move but also because of progressive tectonic changes.
- Systematics: at intervals of days, weeks or years when manual monitoring and permanent data acquisition in automated monitoring systems
- Measurement intervals: at intervals of fractions of a second to several hours
Risk Management
Deformation monitoring systems provide proactive monitoring of potential hazards that could be caused by alteration of natural events or structural objects. Policyholders to minimize before and after a construction project possible risks and get ready for the lifetime of an object insurance premiums on better terms. More information can be found under risk management.