Frequently Asked Questions

Concrete Canvas^® (CC) is the original Geosynthetic Cementitious Composite Mat (GCCM) and the first product to declare conformance to ASTM D8364 ‘Standard Specification for GCCMs’. It is a flexible, concrete filled geotextile that hardens on hydration to form a thin, durable and waterproof concrete layer.

Divert water (if lining an existing culvert). Remove vegetation, soil, gravel and any debris from pervious linings (such as loose bitumen coatings) to expose the corrugations in the culvert.

Damage to the culvert (e.g. voids or pitting created by rust or corrosion) must be filled with concrete, grout or compacted gravel depending on the designer requirements.

Large bolts or protrusions that may cause the CC to snag should be smoothed out using suitable concrete or grout.

If the CC will be terminated in anchor trenches outside the culvert, excavate the leading and trailing edge anchor trenches into the soil at the inlet and outlet.

Anchor trench dimensions must be a minimum of 150mm x 150mm but may need to be increased to suit the designer’s requirements.

Filling the corrugations ensures the material is properly supported, providing optimum durability and resistance to dynamic loading.

If the designer confirms the corrugations are to be filled, this is typically carried out before installing the CC, by using a suitable rapid set, non-shrink grout.

It is recommended to begin at the downstream end of the culvert and work upstream.

Consult the construction drawings to verify if special substrate preparation measures such as substrate drainage details are needed.