Joint gap measurement
Joint gap measurements are used in structural monitoring to determine changes in the distance between two structural parts separated from one another by a joint or a crack .
application
With this method, horizontal movements of the individual wall sections at dams can be recorded. When monitoring of heavy gravity dams , the displacement of the concrete blocks, depending on the concrete temperatures is recorded. Another application is the metrological control of structural cracks.
Measurement method
The measuring points (bolts) are marketed at the same distance from the joint and at the same height. The distance between the two measuring points is 20 to 30 cm. The distances are recorded with the help of micrometers , calipers or dial gauges , which allow a reading accuracy of ± 0.01 to ± 0.1 mm. The measuring equipment used must be checked with a length standard before each measurement. With the combined joint gap measurement, in addition to the relative movement perpendicular to the building joint, the parallel displacement is also obtained. The prerequisite is the arrangement of three measuring pins that form an equilateral triangle.
See also
literature
- Fritz Hennecke, Hans Werner: engineering geodesy, applications in construction and plant engineering. VEB Verlag für Bauwesen, Berlin, 1986.