Deformation monitoring

Deformation monitoring (also referred to as deformation survey) is the systematic measurement and tracking of the alteration in the shape or dimensions of an object as a result of stresses induced by applied loads. Deformation monitoring is a major component of logging measured values that may be used for further computation, deformation analysis, predictive maintenance and alarming. Deformation monitoring is primarily related to the field of applied surveying, but may also be related to civil engineering, mechanical engineering, construction, and geology. The measuring devices used for deformation monitoring depend on the application, the chosen method, and the preferred measurement interval. Measuring devices (or sensors) can be sorted in two main groups: geodetic and geotechnical sensors. Both measuring devices can be seamlessly combined in modern deformation monitoring. Geodetic measuring devices measure georeferenced (relative to established locations outside the monitoring area) displacements or movements in one, two or three dimensions. It includes the use of instruments such as total stations, levels, InSAR, and global navigation satellite system receivers. Geotechnical measuring devices measure displacements or movements and related environmental effects or conditions without external georeferencing. It includes the use of instruments such as extensometers, piezometers, pressuremeters, rain gauges, thermometers, barometers, tiltmeters, accelerometers, seismometers, etc. Deformation monitoring can be required for the following applications: Dams Roads Tunnels Bridges and Viaducts High-rise and historical buildings Foundations Construction sites Mining Landslide areas Volcanoes Settlement areas Earthquake areas Deformation monitoring can be manual or automatic. Manual deformation monitoring is the operation of sensors or instruments by hand or manual downloading of collected data from deformation monitoring instruments.