Case Study - Clydebank

The towpath of the Clydesdale Canal is a popular local amenity and caters for walkers, ramblers and cyclists. It's popularity was causing the exsiting, unbound, granular surfacing to deteriorate rapidly.

British Waterways had designed a scheme to renew the surfacing with a cement-bound mixture incorporating a PFA cement replacement. The towpath was to be graded and it's level raised by the addition of Granular sub-base Material Type 1. The thickness of the Type 1 layer was 50 - 75mm.

The material was then mixed insitu to a depth of 200mm at the same time incorporating the cement binder and any additional water needed to adjust the moisture content to within the range needed for compaction.

The narrowness of the towpath compared to the stabilising plant, the weakness of some sections of the path subgrade and the close proximity of old fragile buildings meant that the usual size of plant could not be used. Another problem was that access to each section of path was from one end only ; this, coupled with no passing places meant that the usual sequencing of plant operations was severely restricted.

After careful consideration, CS and the Main Contractor devised a method of 'in and out' operating that enabled the processing to be carried out successfully. On the successful completion of this stage of the work, a second contract was subsequently awarded.