CC Remediation | A4060, Merthyr Tydfil
CC8® used to Remediate Channel along A4060
Project Overview
In March 2017, Concrete Canvas® GCCM (CC) was used to remediate a channel which runs alongside the A4060 in Dowlais, Merthyr Tydfil in South Wales.
The A4060 links the A470 Pentrebach roundabout and Dowlais areas of Merthyr Tydfil. The Pentrebach end of the route consists of a 3-lane single carriageway, while the newer stretch which leads towards Dowlais consists of a dual carriageway.
Running adjacent to the A4060 lies a large drainage channel, approximately 410m in length with a variable profile of between 5.5 – 10 linear metres, which takes surface run-off from the hillside, protecting the A4060 from flooding and undermining.
The original earth channel had been remediated using several different methods over the years, including a concrete poured invert, cement filled sandbags to stabilise the batters, concrete slab-work and lean mix grout pours. The dilapidated channel was in disrepair, with significant vegetation growth, collapse and signs of scouring. This would eventually have led to undermining of the embankment on the near side of the A4060.
Solution
Insitu poured concrete or concrete slabworks would have been the best alternatives to CC for this project; however, CC is much less weather dependent than insitu which reduces programme disruption and is significantly quicker to install. Typically, CC is installed at ten times the rate of poured concrete solutions. CC also has much greater abrasion resistance compared to conventional concrete methods, a minimum design life of over 50 years and excellent chemical and UV resistance.
Compared to slab work, CC involves significantly less manual handling on site and requires less ground preparation. Slab work can also be prone to joint and mortar cracking and subsequent vegetation growth over time which can introduce water blockages and reduce the performance of the channel. CC also provides excellent weed suppression, and can withstand shear forces of 575Pa and flow rates of 8.62m/s.
Design & Installation
- Channel was re-graded prior to installation
- CC8® Bulk Rolls specified
- Transverse layup
- Screwed joint used on soil substrate
- Concrete masonry bolts used on existing concrete structure
- Edges of CC8® secured within anchor trenches
- Hydrated using a water tank
Summary
A total of 2,875m2 of CC8® were installed over a 4 week period by a team of 6, in inclement and challenging weather conditions. The re-alignment, widening and lining of the channel will protect the A4060 from flooding and closure, which would otherwise cause significant delays and cost to an important trunk route.