Culverts an integral component of infrastructure projects
29 April 2019 | Web Article Number: ME201914317
THE main function of culverts is to manage the flow of water from one side to the other of an ‘obstruction’. This can be a road, railroad, trail or other structure constructed in either the natural or designed flow path of the water.
Factors to be considered before design and installation are the site specific application, environmental impact ensuring that erosion is minimised and structural damage avoided. Incorrectly placed or designed culverts can result in culverts failing, becoming dislodged and in extreme pollution cases being clogged with vegetation and sediment.
Precast concrete product manufacturer Rocla is a supplier of a wide range of culverts for infrastructure and other water flow related projects, including many major infrastructure developments such as Polokwane Eastern Ring Road and the rehabilitation of the D528 in George’s Valley, Limpopo.
Along with custom designed culverts for once-off projects, Rocla offers two distinct ranges of culverts, differentiated by the type of loading requirements, both available with associated precast base slabs.
For Heavy Loading Applications, such as to provide a waterway below railway tracks, Rocla’s SATS SAR Rectangular Portal Culverts can be used. These, or custom units are also utilised in any application with excessive fill requirements with the culvert tunnel at the base of the fill zone, allowing either conveyor or vehicle access.
The standard SAR culverts are supplied in lengths of 1,22m and designed for up to 10m of fill. Culverts required for loading heights greater than 10m are handled individually and designed in-house at Rocla Head Office.
For traditional loading applications, creating waterways below roads, trails or even drainage channels, Rocla’s Standard Rectangular Portal Culverts are the preferred solution.
These standard culverts range in size from a span of 450mm to 3600mm, and heights from 300mm to 3000mm. The strength classes for these culverts are 75S, 100S, 150S, 175S and 200 If time constraints are a factor for any project, the Precast Culvert option, along with the Precast Base, as opposed to casting in-situ, will save on project duration and provide quality assurances on final product.
Rocla’s Precast Wingwall units can be used at both the inlet and outlet of any channeled system making use of circular or rectangular portal culverts for stormwater applications. The natural flow path of water upstream of a construction is often wider than the culvert or pipe structure. Transition sections are then required to receive and direct the flow of this upstream water through the culvert/pipe.
The same is true of the downstream end of the culvert/pipe section. The precast concrete wingwall unit is the most effective structure to use for the effective transfer of this water, eliminating erosion and creating a smoother flow of water.
Rocla is part of the ISG which also includes Technicrete.