Geosynthetic reinforcement design workshops to visit KwaZulu-Natal and Cape Town.

 On the back of the success of its technical workshop series on walls and slopes systems hosted in Midrand, Polokwane and Nelspruit towards the end of last year, Kaytech is planning to also roll out these workshops to centres in KwaZulu-Natal and Cape Town in 2014.

Presented by Kaytech’s marketing director, Garth James, and technical marketing engineer, Samantha Naidoo, the workshops revolve around utilising Rockgrid PC designs for specialist geo-synthetic reinforcement.

Per illustration at the workshops, Rockgrid was used successfully in these projects:
• Constantiakloof – basal reinforcement.
• Gautrain – reinforced platform.
• Mondi Richards Bay – basal reinforcement.
• Mponeng Mine – retaining wall reinforcement.
• N6 Queenstown – road reinforcement.
• N14 – sinkhole remediation.

James’ presentation on polymers and their behaviours and intrinsic product qualities includes the topics of soil reinforcement with geo-synthetics and using geo-grids in soil reinforcement, while Naidoo’s presentation focuses on the design of basal reinforcement and steep slopes and walls.

Rockgrid PC is the first specialist composite reinforcing geotextile to be manufactured in South Africa, and offers the reinforcement characteristics of geo-grids and wovens in conjunction with the favourable hydraulic qualities of non-wovens.

The non-woven geotextile component, which offers optimum hydraulic characteristics and high resistance to installation stresses, is strengthened with high tenacity, multifilament yarns. In addition, the non-woven layer protects the reinforcement elements during the critical installation phase, thereby ensuring a safer optimum performance.

Wherever soft soils with low bearing capacity are encountered, Rockgrid PC can be used as an effective and lasting reinforcement. Even wet, more cohesive soils can be utilised as fill-in steep, retaining structures because the Rockgrid PC helps to drain the fill and accelerate the consolidation process. This makes soil exchange and the import of expensive fill material unnecessary, saving both time and money.

The major difference between polymeric geo-synthetics and more traditional materials is the time-dependent viscoelastic behaviour of polymers. Creep is the continued extension or deformation of a polymeric part under continuous load. It results from the viscoelastic flow of the polymer with time. For the design of structures this reduces the allowable tensile strength in long-term behaviour. With its high-strength multifilament polyester yarns, Rockgrid PC demonstrates a very low creep tendency as opposed to polyethylene grids, polypropylene grids or woven fabrics. 

In the case of conventional open geo-grids, no preferential flow routes are available, which means that pore water can only be slowly drained away, thereby causing reduced stability. Woven fabrics offer very little drainage capacity. This can result in the formation of slip surfaces in the fabric/soil interface.

Rockgrid PC provides sufficient drainage capacity, enabling it to drastically reduce the flow paths in the reinforced soil. Due to its water transmissivity within the plane of the product, Rockgrid PC facilitates the reduction of pore water pressure and improves shear characteristics, thereby increasing stability.

Kaytech invites interested parties to contact them with a view to providing seminars to train staff on the techniques and benefits of geo-synthetic engineering.

Kaytech
Tel: 031 717 2300
Website: www.kaytech.co.za