Geotech

Beefcor’s Bayview Feedlot, situated outside Bronkhorstspruit, comprises 16 pens with a total capacity of some 40 000 cattle. The feedlot operations also include trading with the by-products from the operations (i.e. manure) and as such the roads experience high traffic volumes consisting of large interlink trucks, tractors etc. that contribute to the deterioration of these roads.

The consistency of the various roads’ subgrade material was determined by conducting a range of Dynamic Cone Penetration (DCP) tests. These consistencies were used to empirically derive the strength of the in-situ material.

Possible aggregate quarry areas for the layerworks material were identified and its suitability was investigated by means of test pit investigations from which samples were obtained and sent to the accredited Matrolab laboratory for a variety of tests. The tests were conducted in order to determine the material’s grading (including clay content), California Bearing Ratio (CBR), moisture-density relationship (MOD) and Atterberg limits.

The laboratory and DCP test results were utilised to design appropriate layerworks for the new roads, which mainly comprised a new surfacing layer of 175mm. The turning area adjacent to the weighbridge experienced high lateral stresses caused by heavy vehicles. In this area, the layer thickness was increased to 200mm and stabilised with 3% cement to produce a C4 stabilised layer with increased stiffness to better accommodate the high lateral stresses and resulting strains.

Photos below depict: a) Turning area adjacent to the weighbridge, b) layerworks material placed for distribution, c) grader distributing material prior to compaction

Project details