Box Culverts

Precast Concrete box culverts are rectangular (or square) shaped sections that are generally combined to form under passes, conducting streams, pathways and drains under embankments or roads. Precast Concrete Box Culverts are generally cast and delivered to site in 2 m long sections, and joined together to form passage ways through the structure that will eventually be placed over them.

Precast Concrete U-shaped culverts can also be cast, when access is required from above to the culvert. Lids can be cast for these units, which allow the user to have to culvert covered over or accessible, as required.  These are often used when pipes or other equipment that may require mantenance are stored below ground.

They are designed to withstand the vertical and horizontal pressures from the earth and other superimposed loads, and are available in sizes up to 3.6m high and 6m long.

Head walls and wing walls are often required at the entrances to culverts. Concast can also cast these items.


Head Walls

Head Walls are used at the entrances to box culverts to retain soil above the entrance. They are cast as thin wall panels or beams, which bear directly on top of the culvert.

They are generally held in place between the wing walls on either side, and are also doweled into position. These units can be cast to any size or shape required by the client, and will be installed with the retaining walls on site.

These walls can be cast with a variety of finishes, as required by the client and depending on the requirements of the individual structure.



Wing Walls

Wing walls are sloped retaining walls, which are placed at the entrance to a culvert, to allow the soil to incline to the full height in the area.These units are often combined with our head walls and culverts to form the entrance to culvert structures.

They can be cast with any of our typical retaining wall sections, and are easily installed on site.The two main systems for retaining walls are the insitu heel and single heel systems, as can be seen on our retaining wall page.

The wing walls are easily installed on site, and can be loaded as soon as the insitu pour has reached design strength. Precast single heel system can be loaded straight away. These walls can be finished in any of our standard cladding panel finishes