In any construction project, bad ground conditions can create a wide range of problems and can even bring construction to a halt. This is why when Peter Harding Construction began work at St Wilfreds Academy in Blackburn, they knew they needed a drainage solution. The solution had to combat the poor ground conditions, not hinder the efficiency of their work, and ensure the health and safety of their team of workers.
After evaluating the site it was decided that orifice chambers and Hydro-Brake chambers were needed. However, this created problems relating to budgets and offsite design. BPDA member Marshalls CPM offered a solution by providing a full package of sealed 1200mm and 15000mm perfect manholes. They also provided off-site solutions for orifice and Hydro-Brake chambers. This allowed for many problems relating to chamber overflow to be overcome.
The Perfect Manhole system was used where possible. However, eventually, it was decided that due to the unusual ‘S’ style shape of the channel, a 1500mm sealed Catchpit that utilizes an offset inlet and outlet would be well suited for the project as well.
In addition, the client was presented a variety of pipeline design options. While plastic pipework was considered, this required using Class S Bedding. It was settled that precast concrete pipes would be the most ideal solution. This allowed for a lower overall cost and a reduced environmental impact as precast concrete pipes were installed with Class N bedding, which meant use of imported aggregate could be reduced.
The final result was an effect drainage solution that improved the poor ground conditions and accelerated the installation of the drainage requirements.
To read more please visit the BPDA website.