Vibrating subsoilers

VIBRATING SUBSOILERS. These machines were developed for the purpose of achieving a loosening effect not only through the tractive power but also through the power take-off of the tractor. In this way it is possible to loosen the soil even if the surface does not give a firm hold or the machine has to work uphill. The movement of the shanks to and fro is driven by an eccentric drive. 

Measurement and assessment of ground vibrations Table 16 Propagation velocity of elastic waves in the subsoil... 

The frequencies of the vibrations depend more particularly on the nature of the subsoil. Compact and solid rock has only a low damping capacity, and the frequencies are relatively high (20 to 60 Hz). A subsoil which is less strong or is of a more yielding or plastic nature will develop a greater damping effect, so that the vibration frequencies are lower (5 to 20 Hz). 

The zone of compaction around a single probe, and thus the required probe spacing, will vary with a radius ranging from 3 to 5 m according to the nature of the subsoil and the type of vibroflot used. As for most compaction techniques, a trial must be executed at the actual project site to establish the optimum grid spacing, frequency and amplitude, and the vertical vibration interval to achieve the required degree of compaction. 

Tilted buildings are signs of uneven loading of subsoil (Fig. 2g). When seismic vibrations act on water-saturated soil, it loses coherence and behaves like a fluid. Building foundations - losing support during liquefaction events - suffer differential... 

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