Concrete products manufacturer and supplier Technicrete reports that its hydraulic hardening construction material HT33 grout, used for stoping in the gold mining industry, is a cost-effective way of improving production and safety.

“Mining activities that are conducted above or below ground, need quality products and equipment, to conform to operational and safety standards,” the company states.

The company also offers a thin skin liner (TSL), which is used as a rock support. The prebagged polymer-based reinforced liner provides surface stabilisation between rock bolts.

The Technicrete TSL is water based and supplied in an easy-to-use kit, with one kit providing 13.5 ℓ of mixed material, which would cover around 3 m2 to 4 m2 of rock surface with a 4 mm thickness, depending on the roughness of the sprayed face. It has a pot life of 15 to 20 minutes at between 28 °C to 32 °C.

The TSL can be applied quickly, which the mining industry requires for a ‘Make Safe Solution’. It can be sprayed over rock to stabilise and to prevent oxidation of the rock and the unravelling of the rock mass, thereby preventing rock falls.

The contents are emptied into a mixer/pump arrangement and sprayed onto a cleaned rock face. The spray is directed into any open joints for maximum protection. The tensile properties of the TSL spanning across joints and cracks resists shear and direct tensile movement, adding to stability in the rock mass, for additional safety.

Technicrete TSL easily exceeds the speci-fication of the European Federation of National Associations Representing for Concrete.

It is suited to underground activities and is easily used in confined areas.

The cleaning of the equipment is simplified and is done by flushing and washing with clean water, which reduces pump and hose blockages, and allows easy maintenance of the application.

Technicrete offers prebagged products, stope support systems and services to the gold and coal mines. Mining products are manufactured in Stilfontein, Carletonville, Welkom and Evander and are distributed throughout the country.

HT33 grout is used for civil work and used in coal mining to construct high-pressure dam seals, as well as in the gold mining industry for stoping, winch beds and more.

The company claims that the grout is beneficial when the placing of concrete is in areas that are difficult to access, owing to space constraints. “It has good lubrication properties and can be pumped in small diameter pumps over long distances. It is self-levelling and self-compacting with an open time of 300 minutes,” it adds.

The grout has been commonly used to seal old workings and shafts owing to its lack of shrinkage while, at the same time, eliminating the ingress or escape of water and gases. It is supplied in cost-effective 25 kg bags or delivered in bulk depending on the customer’s requirements.

“Most mines use sand, ash and gravel to construct their roadways, while some use concrete, but at a higher cost, owing to steel reinforcement being required. While consid-erably cheaper, the sand and gravel option often leads to the formation of excessive mud/water potholes. These disadvantages, as well as the high-cost elements of the concrete option, can be avoided with Technicrete’s Deckwerk, which has been used in heavy-duty applications for more than 30 years, and in some instances is still meeting the requirements in performance and longevity,” it states.

Technicrete’s Deckwerk product is a heavy- duty paver, which can be used for under-ground roadways as well as heavy-duty sur-face applications.

Deckwerk can significantly reduce down- time at a mine, a costly activity for mining operations, as it can be installed while the roads are still being trafficked. A unique fea- ture is the three-way mechanical interlock, which maintains the integrity of the surround-ing blocks while resisting uplift forces.

This product has been installed in many mining operations, and offers benefits such as prevention of tyre damage owing to sharp rocks cutting or protruding from the roadway; less wheel bearing failures, as deep mud and water are eliminated; no more transmission and hydraulic hose failures; and the attainment of more constant speeds, as drivers does not have to navigate potholes, which also means that less fuel is wasted.

The improved roads also improve the delivery of rolling stock.

Further, the company explains that there is no need for the installation of drains, as the water can be channelled up against the sidewall of the road. The Deckwerk product can also be used as an erosion protection system in lining of canal floors and wall sides.

Deckwerk is suitable for surface and underground installations, from container yards, warehouses, underground incline shafts and heavy-duty workshop floors. It can also be designed to meet additional customer requirements encompassing high compressive strengths and abrasion-resistant properties.