Slough Sewerage Treatment Works needed significant modification to increase capacity and improve water discharge quality in line with the latest EU regulations.
The work involved remodelling an existing concrete structure so that new metal channel division walls could be introduced – a programme that had to be scheduled to coincide with a period of anticipated low rainfall because this part of the plant would need to be shut-down but the Works still needed to be able to cope with overall flow rates.
Technical Concrete Cutting (TCC) surveyed the project and instead of the demolition method originally envisaged by the plant engineers, the company recommended using diamond wire sawing to create the new structure for the channels.
CC used its expertise in this process to diamond wire saw cut into sections the 1.2m wide reinforced concrete walls of 6m long and 2.5 m high between sewerage flow channels within the building. Holes were then diamond drilled through each section and a sling passed through to enable a gantry to lift the 3 ton sections of concrete from the work area into skips.
The benefits of diamond wire saw cutting were immediately visible as no remodelling to the remaining concrete structure was required and the new metal channel dividing walls were then able to be bolted straight onto the clean saw cut faces.
This had the advantage of saving a great deal of time over the period of the project, as Nigel Ostler-Harris of TCC explains: “The diamond wire saw cutting was so quick compared to the demolition method originally envisaged by the Treatment Works that the work ceased to be a critical path item in the project; the Mechanical & Engineering plant installation then came into the critical path instead.”
The project was completed over a period of five days, with health and safety issues given a great deal of consideration. Operatives did not have to handle any debris manually and water suppression meant there was no dust. The wire sawing method also meant noise was kept to a minimum, which meant that work could continue through the weekend with no disruption to nearby houses.
TCC also ensured that 100% of the debris was taken away for recycling.