Construction World February 2015

PROJECTS AND CONTRACTS

When Advance Projects was awarded the contract to construct a platform onto which the new warehouse would be erected, the company was unaware that the geotechnical report on existing in-situ conditions were sub-standard. Confronted with variable soil condi- tions, it soon became evident to the contractor that surrounding projects had used this site as a ‘borrow pit’ for all their rubble and low-grade soils. Difficult working conditions on site were rendered virtually untenable when sub-surface water and heavy rains wreaked havoc on excavation attempts, with heavy machinery getting stuck in the already weak mate- rial. The contractor persevered however, constructing layer upon layer a number of times without success. It was at this stage of the project that Kaytech was consulted. At a site meeting held with BSM Baker Consulting and Advance Projects, Kaytech’s technical field staff realised that this was an ideal situation for a high strength RockGrid PC to prove its efficacy. They also explained what amount of fill material and layerworks on site would be ideal to cover the RockGrid PC layer to place it under sufficient tension. The first composite reinforcing geotextile to be manufactured in South Africa, RockGrid PC consists of a nonwoven layer in conjunction with high tenacity, bi-axially orientated, multifilament polyester yarns, During construction of Raceway Industrial Park, in Germiston, Gauteng, a unique Kaytech geotextile solved a severe subgrade stabilisation problem. > RACEWAY INDUSTRIAL PARK RESCUE

The 29 000 m 2 of Rockgrid PC was used to reinforce the substrate.

the combination of which guarantees the unique characteristics of the product. The high tensile modulus of RockGrid PC provides excellent reinforcement characteristics andminimum creep deformation compared to polyethylene or polypropylene grids or woven fabrics When the technical field staff’s recommendation was accepted,

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CONSTRUCTION WORLD FEBRUARY 2015