Precast concrete trends to provide the necessary quality control and design manuals coupled with a design service.” Production of blocks is automated to a large degree, cured under controlled conditions, stacked and stored with regular testing of blocks conducted. The fact that precast CRBs (concrete retaining blocks) have a much lower carbon footprint than conventional methods has been well documented.
Concrete aesthetics can be pleasing Concrete retaining walls do not have to look dull. A reputable walling contractor should be able to supply a design, or one endorsed by an engineer, for a retaining wall that is pleasing to look at, and complementary to the landscape it is placed in. A good example for simple, yet good design is the featured family garden that was designed in a sustainable and attractive fashion. Says Simon van Blerk of Decorton, a Terraforce approved contractor: “I was contacted by this family for some advice on enhancing the recreational appeal of their back garden. Proposal and quotation were accepted and weeks later the family had a significantly transformed garden to enjoy.” Apart from the meandering terrace walls in a rockface finish, two small sets of steps were installed. In this manner safe and easy access was provided to a raised area of the garden. Maintenance of level platforms is easy, compared to mowing on the slope, as any gardener will confirm.” Of particular interest, says Van Blerk, is the small curved set of stairs next to the pool, rounded to match the adjacent terrace walls that were packed in a circular shape: “Installed on a concrete foundation and filled from the side with a fairly dry concrete mix that was compacted with a pick handle, the blocks were fanned out only slightly, so that the gaps that opened up between the blocks towards the back were hardly noticeable.” No corking or grouting was deemed necessary, according to the client. This would be an important requirement on installations with a tight radius or where triangular wedges have to be cut from standard 4x4 Multi Step blocks to form sharp corners, curves or tricky details. In such instances, reinforcing becomes a necessity to avoid excessive cracking of the grouted joints. Overlapping lengths of reinforcing steel – 4mm diameter minimum – would then be pushed into the moist concrete mix that is used for filling the blocks, and once the blocks are placed in their proper, level position. n
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Concrete Trends Issue 2 2022
