Construction World June 2021

GEOTECHNICAL ENGINGEERING

PILING AT VAL DE VIE G eopile Africa was registered in 2004 as a special foundations and piling contractor under the GeoGroup of companies

in vertical axial load and 50 kN in lateral load. With any project, one can always expect to face unforeseen challenges. The main obstacle the crew had to overcome was the sub-soil conditions, with a boulder and cobble lens in a matrix of coarse sand, which extended approximately 3-4 metres below the blinding level. With the help and drilling expertise from Geomechanics, Geopile Arica was able to overcome this obstacle by pre-drilling the pile locations using the Atlas Copco Symmetrix casing advance system. The temporary casings were then grouted up with a 1 mPa bentonite grout before being removed. This provided a clear path for Ductile iron piles to be installed in an open-ended style through the boulder layer

and into the shale bedrock. The Piles, driven to refusal with the Atlas Copco HB2000 hammer, self-socketed into the shale at 10-12,5 m below the pile cap. In some cases, the depth of penetration was as deep as 4,5 m into the shale. The variety of the depths were all dependent on the competency of the shale at that point, this was guided by the “set” achieved on each pile installed. This was a challenging project for Geopile Africa but with teamwork and drilling expertise from Geomechanics, 338 end- bearing piles were installed, constituting 2 900 linear meters of Ductile iron material all done in nine weeks on-site. Proving Geopile’ s system is Safe, Fast and Simple. ▄

which compromises of Geomechanics, Geomech Africa, Geopile Africa and Terra monitoring. Each company plays a key role in the mining, civil, exploration and geotechnical fields. The expertise of the GeoGroup ranges from Geotechnical drilling services to in-situ testing and monitoring as well as foundation solutions. In 2011, Geopile Africa brought the TRM Ductile Iron Pile system to South Africa which has been a trusted foundation system in Europe for over 30 years. This unique patented 'Plug and drive' joining system, in combination with a pile shoe ensures a watertight core which is easily filled with concrete to create a high-quality composite pile. The ductile iron pile system is simpler, faster and safer than any other piling system on the market. EMPA structures contracted Geopile Africa to install a Ductile Iron Pile Alternative piling solution to replace the originally specified 610 mm lined oscillator piles. This was done in a ratio of 8:1. Geopile designed and installed the alternative 170 mm diameter, 9 mm wall thickness Ductile Iron Piles for the new access bridge over the Berg river which was recently completed. The piles are designed to take a maximum of 825 kN in vertical axial load and lateral load of 2 kN per pile. The piles can take as much as 1 200 kN

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