With time constraints being an issue, Blackley Construction were engaged on a labour/ machine-only contract to install twin 1350mm Diameter concrete pipes through a stopbank. Whittikers provided the grade and alignment as the requirement was to maintain flood protection at all times. The first section of pipes had to be laid and then the stopbank relocated over top of them to provide this flood protection. The second section of pipes were then laid on foundations that included weak flowable concrete, a seepage collar and finally polystyrene.
Laying pipes on polystyrene provided many challenges as the sinkage of the pipes into the polystyrene had to be allowed for. The pipes were laid to grade and on line. Once the pipe-laying was complete, Blackley Construction relocated the stopbank a second time back to its original alignment. This was compaction tested as it was constructed, with all tests passing.
Key features of the work and/or Statistics
- The project involved us laying to grade twin 1350mm diameter concrete pipes through a stopbank to match up with the outfall of a pump chamber.
- We installed a total length of 90m of pipe.
Key equipment used:
- Compaction rollers & hand compaction equipment
- Rotary Lasers
- Kobelco SK210, SK135 & Hitachi ZX 200 excavators
