Vibro replacement

In soils containing strata of silt and clay, those strata may not densify and the overall deposit may not benefit from vibroflotation. However, the probe will create a zone of displaced material which can be filled from the surface with stone aggregate as the probe is withdrawn. These stone columns can then be used for structural support. This process is often referred to as vibro-replacement. Table 3.3 and Fig. 3.8 shows the vavious soils for which vibro-treatment is effective. 

Type of soil Vibro-compaction Vibro-replacement... 

Vibro-replacement Hole jetted in soft, fine- Very soft to firm soils 60 Stone grain soil and backfilled (undrained strength 0.2... 

Typical execution methods are based on the vibro-replacement technique or on the insertion of a closed-ended casing by vibration or driving. During extraction of the probe or casing the gravel is compacted and a further enlargement of the column diameter is realised. Only the more frequently used vibro-replacement technique will be further discussed in this section. 

Execution of stone columns by the vibro-replacement technique... 

The wet vibro-replacement (see Figure 7.21) based on both replacement and displacement comprises the following steps (see www.keller.co.uk) ... 

The grain size distribution envelope in Figure 7.22 indicates when vibro-replacement should be used instead of vibro-compaction. 

Soil improvement methods include techniques such as surcharging (in combination with vertical drains), compaction, deep soil mixing and vibro replacement (see Chapter 7). 

Priebe, H.J. The design of vibro replacement. Reprint from Ground Engineering, Technical paper GT 07-13 E, December 1995. 

Vibro-replacement the cavity formed by probe penetration is filled with imported materials, such as crushed stone gravel and sand. 

Vibro-replacement methods can improve Uquefiable soil deposits not only by densification... 

In VCD, the differential absorption of left and right circularly polarized infrared radiation by a vibrational transition of a chiral molecule is observed. Equations (1-5) hold equally well for electronic and vibrational transitions, but in all transition moments, the electronic wave functions need to be replaced by vibrational (or vibro-nic) wave functions. In vibrational CD, the ratio of differential absorption to the infrared absorption, defined as... 

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