The utility industry is regularly required to call on an enormous and varied range of specialists; from mapping, to drilling, to wastewater treatment, to asset management, to pipe relining, to pipeline integrity, to land access, to risk management, and the list goes on. To make the process a little easier, Utility magazine is bringing together experts from various fields to answer your questions.
What are the best practices when planning a microtunnelling project that needs to be completed within a tight timeframe?
Undertaking a microtunnelling installation within a tight timeframe can increase a project’s difficulty. However, certain measures can be taken to ensure that pipe installation is completed swiftly and efficiently with minimal hassle.
Working within a tight timeframe requires a lot of pre-planning. Unexpected ground conditions, poor weather and mechanical failure all need to be accounted for, as there is always need for a ‘Plan B’ if something goes wrong.
Changing ground conditions
Contingency plans for changing ground conditions must be in place before beginning work. Test pits can be constructed at each end of the bore prior to project commencement.
It is also a good idea to prepare a selection of cutters suited to a range of different ground conditions to allow for changes during the drilling process.
Mechanical failure can cause major project delays, and on projects needing to be carried out within a tight timeframe, this can be a very costly problem.
To reduce the risk of mechanical failure, it is recommended that all equipment is serviced, tested and made ready for operation prior to construction.
Having spare parts available is also a must, and a back-up drilling machine should be on standby in case of machinery breakdown.
Selecting the most appropriate and effective tools for a job is a straightforward consideration, but it makes a big difference when it comes to projects with time constraints.
Providing back-up equipment in the case of poor weather must also be considered. Access roads to the site can be washed away quite quickly in heavy rain, so having equipment such as earthmoving machinery on hand will allow you to continue operation.
All-weather access to a tipping facility should also be arranged to account for the disposal of drilling mud created during construction.
Supply of materials
On fast turnaround projects, there is no time for modifications of any materials on site. Everything from steel jacking bands, concrete jacking pipe, joint packers, centralising brackets and carrier pipework should all be measured and trialled before the shutdown.
Prebooking of facilities such as a concrete batching plant for grout supply during a project must also be taken into consideration, especially if the project is to be completed after hours or over a weekend.
Self-sufficient crews that can supply their own transportation are key to orchestrating personnel to job sites for fast turnaround projects with minimum hassle.
Fully-mobile teams are then able to work on multiple job sites at once, giving contractors more option when scheduling works. This also means that extra labour can be brought into a job site more easily, if the need arises.
About Stuart Harrison
Global microtunnelling pioneer Stuart Harrison is the Managing Director of Edge Underground, where he specialises in ongrade microtunnelling installations with millimetre accuracy.
Stuart is also the inventor of the Vermeer AXIS Guided Boring system, and he is constantly working to improve the effectiveness of this and other trenchless systems used in the installation of gravity sewers.
To discuss your next microtunnelling installation, contact Stuart on 1300 JACKED or at [email protected].