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Figure 3.1. Calculating speed with the acceleration signal.
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Figure 3.2. Acceleration sensor SCA620 used to monitor a road structure. The acceleration sensor components are very small. In practice, the size of a sensor depends on the
way in which it is protected.
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Figure 3.3. Installing acceleration sensors in the asphalt at a test location in Vesilahti.
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Figure 3.4. An example of using acceleration sensors to take measurements of recoverable settlement of a sleeper. The sensors are located outside the rails at the ends of the sleepers.
Figure 3.5. Acceleration sensor AS-20B manufactured by Kyowa.
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Figure 3.6. Principle of a deformation sensor and its various development versions.
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Figure 3.9. The MDD that is to be placed in the embankment is ready to be installed.
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Figure 3.10. Installing MDD. The sensor element was installed in a 50-mm hole made with a
drill rig (on the left) and fixed to its surroundings with installation sand (on the right).
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Figure 3.11. Some of the installation phases of a sensor measuring deflections in the pavement.
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