With a proven track record exceeding 35 years, a Kaytech manufactured geocell recently saved a large retaining wall from possible catastrophic failure. The wall was built by Edilcon Construction to increase the despatch area for the Makro Store in Germiston, Gauteng.
Prior to the summer rainfall season, L & S Consulting Engineers became concerned that surface drains installed above the soil retaining wall, were possibly inadequate and could lead to excess water permeating the backfill. Instead of designing a costly steel-reinforced concrete channel to solve the problem, engineers specified Kaytech’s Multi-Cell (100 mm) and bidim A2, an economical and highly effective system to line the v-shaped surface drain.
Multi-Cell is a honeycombed structure manufactured from strips of coated slit film woven polypropylene tape stitched alternatively together to form three-dimensional diamond-shaped cells with high tensile strength and seam strength. Lightweight and flexible, Multi-Cell conforms to an existing surface, is rot-proof, UV resistant and resistant to most chemicals. Multi-Cell is used as an in-situ shuttering to cast continuous interlocking concrete paving for canal or road construction while further uses include load support applications to prevent shearing and lateral movement of the infill material and as an erosion control formwork where cells are soil-filled for vegetated embankments.
Bidim®, a continuous filament, nonwoven, needlepunched geotextile, is manufactured at Kaytech’s ISO 9001 registered facility where discarded plastic cooldrink bottles are processed to create high-grade polyester. The needlepunching process provides several advantages including appreciable thickness, high porosity and a high drainage capacity. Installed directly over the soil and beneath the Multi-Cell, bidim in this project will have a dual function, that of drainage and separation.
Since the contractor had no previous experience with Multi-Cell, Kaytech gladly provided on-site installation training. Upon arrival on site, Winnie Botha, a Kaytech technical sales representative, discovered neatly completed earthworks including tuck-in trenches on both sides while the layer of bidim A2 was already installed. By receiving appropriate training, the contractor was able to overcome initial installation challenges and rapidly progressed to installing 50 metres of Multi-Cell per day. Using binding wire, Multi-Cell (1 500 m2) was pegged down every two metres to maintain intimate contact with the bidim A2 and soil below. Once installed the Multi-Cell layer was ready for concrete infill.
With tried and tested Multi-Cell and world-renowned bidim meeting the highest civil engineering specifications, there is no doubt that drainage above the retaining wall will be effectively controlled far into the foreseeable future.