Roland Schenkel
Karten 59 Karten
Lernende 6 Lernende
Sprache English
Stufe Universität
Erstellt / Aktualisiert 17.01.2012 / 30.01.2019
Lizenzierung Kein Urheberrechtsschutz (CC0)
0 Exakte Antworten 59 Text Antworten 0 Multiple Choice Antworten
Fenster schliessen

Crack detection (due to geothermic drills in Staufen, Germany). How can you detect the crack shown in the picture?


Fenster schliessen

How can you detect influencing parameters, like temperature?

By measuring them during data acquisition and correlate them to the measurements.

Fenster schliessen

Can geodetic instruments also be used (for crack detection in a building)?

a) Tachymeter an two reflectors on SBB-bolts. b) levelling for sinking problems

Fenster schliessen

What could be the reason for a trend?

* Instrument got warmer

* sinking of the tripod

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Frequency measurement:

Acquisition rate of a Totalstation? Possible for this task?

5-7 Hz (leica says: 10 hz) => possible for lower frequencies.

* When the amplitude is to high for ATR without moving it’s good.

* When the tachy has to move => bad.

Fenster schliessen

Frequency measurement:

Acquisition rate of a GPS? Possible for this task?

20 Hz => possible

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Differences between geodetic and geotechnical instruments?

[Criteria / geodetic / geotechnical], [Accuracy/ mm (Leveling <0.5mm/km Doppelnivellement) / 2μm - mm], [Range / m - km (VLBI :-)) / μm - m], [Measuring in 2 or 3 dim. / possible with 1 sensor / usually 1 sensor for 1 dim.], [Costs/ ? (high) / ? (low)], [Absolute Measurements (Coordinates) / ✓ / ✕], [Development / for classical survey / specially for those purposes], ]Place of instrument / mostly away of the problem / directly at the problem (crackmeter, plumb)|

Fenster schliessen

What is the easiest and cheapest method (to detect a crack in a wall)?

Plaster-Plate (Gips-Platte), take care that the predetermined breaking point is over the crack!