Ground Improvement
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Ground Improvement

Ground Improvement Characteristic Features • Increase in load-bearing capacity • Reduction of settlement • Reduction of soil liquefaction during earthquakes • No excavation – no environmental impact resulting from costly transportation and specialist disposal of contaminated soils • No groundwater lowering – low permit requirements and no risk to adjacent buildings • Resulting foundation conditions equivalent to natural soils with an adequate loadbearing capacity • High environmental compatibility by using only natural fill materials • Self-exploring processes – intrinsic adaptation of...

Deep Vibro Techniques – Over 45 years’ experience Bauer designed and built the first depth vibrator based on a hydraulic drive Collini-Center, Mannheim, Germany, vibrodisplacement stone columns 50,000 m³, depth up to 12 m Las Palmas, Gran Canaria, vibroflotation process 250,000 m³ Thuwal, Saudi Arabia, vibroflotation process 160,000 lin m, harbour works – new quay wall, work carried out from pontoon Cardiff, Great Britain, vibrodisplacement stone columns 24,000 lin m, depth 9 - 10 m, road embankment Singapore, vibrodisplacement stone columns 230,000 lin m, depth 9 - 10 m, soil stabilization...

Deep Vibro Techniques In many cases, deep vibro techniques offer a fast and economical method for improving the engineering characteristics of a prevailing subsoil. Vibro Concrete Columns Applicable in non-cohesive to slightly cohesive soils such as sand and gravel, as well as in slag heaps. Suitable for carrying high loads on the improved subsoil, including dynamic loads. Very low foundation settlements. Particularly economical application in fully saturated soils below the groundwater table. Applicable in mixed-grained soils, such as sandy silt, to cohesive soils with undrained shear...

The vibroflotation process (VF) is used to densify soil formations which do not have an optimum relative density - mainly naturally deposited or backfilled granular soils, such as sands and gravels. Under the influence of the horizontal vibrations generated by the oscillating vibrator, the soil particles are rearranged and adopt a denser packing. After reaching the final depth, supported by water jetting, the depth vibrator is gradually retracted creating a densified zone of 2 to 4 m in diameter. The reduction in pore volume is evidenced on the surface by the formation of a settlement crater...

Soils with fines content of more than 10 % can no longer be rearranged and densified by vibrations. Here, the achievable ground improvement consists in the construction of loadbearing stone columns. With the VD wet “Top Feed” process, the depth vibrator is lowered to the specified depth supported by water or water/air flush. Backfill material is then introduced at the ground surface to the annular space created by the vibrator and moves through the annular space to the vibrator tip. By repeatedly raising and lowering the vibrator in steps of around 0.3 to 0.5 m, the backfill material is...

Vibrodisplacement – VD “Bottom Feed” Soils with fines content of more than 10 % can no longer be rearranged and densified by vibrations. Here, the achievable ground improvement consists in the construction of load-bearing stone columns. With the VD dry “Bottom Feed” process, a leader-mounted bottom-feed vibrator is lowered to the specified design depth assisted by air flush and positive crowd pressure. The surrounding soil is displaced laterally as a result. The coarse granular backfill material is delivered directly to the tip of the vibrator via a material transfer hopper and a material...

Vibro Concrete Columns – VCC Vibro concrete columns are used when fine-grained soils are unable to form a load-bearing bond with stone columns or the lateral support is too low. The surrounding soil is not, or only marginally, compacted. Non-load-bearing soil layers are “bridged” by rigid load-bearing elements. After reaching a load-bearing foundation level, the vibrator is partially retracted and concrete is placed under constant pressure through the concrete feeder pipe attached to the front of the vibrator into the cavity formed by the vibrator. The column diameter is broadly equivalent...

Crushed Stone, Sand and Gravel Columns – VIPAC The VIPAC process is a technique for constructing sand and gravel columns simply and economically. The displacement work is carried out by vertical vibrations that are generated by a vibro hammer. The high hydraulic power required for this process is provided by the base machines of the RTG RG series and BG PremiumLine machines with auxiliary power pack. The process involves repeated raising and lowering of the vibrator tube. The resulting column diameter is generally slightly larger than the diameter of the tube. A telescopic loader can fill...

Bauer Dynamic Compaction – BDC BDC (Bauer Dynamic Compaction) is particularly suited for increasing the relative density of non-cohesive granular soils and loose mixed soils with low fines content. The process involves dropping a heavy weight (pounder) repeatedly on the ground at regularly spaced impact points. The kinetic energy released on impact penetrates into deeper soil formations and, as a result of the forced rearrangement of the soil particles, leads to compaction. The degree of compaction depends on the mass of the drop weight, the drop height and the spacing of the impact points....

Technical Specifications Centrifugal force Eccentric moment Power output Overall weight incl. follower tube (VF) Penetration depth Diameter of pre-bore if required Follower tube Isolator c/w elastic coupling Depth vibratorTR 17 Standard Hydraulic motor Eccentric weight c/w material transfer pipe c/w material transfer pipe The horizontal vibrations of the depth vibrator are generated by a hydraulic motor driving an eccentric weight, housed inside the vibrator section. The length of the depth vibrator can be adjusted to suit the prevailing site conditions by the addition of follower tubes....