The Akkerman SL60C-72 outfitted with a dual- gage soft ground cutterhead is shown being delivered to the jobsite. The Akkerman MTBM received an increased kit to 72-in OD that included a belly-pan kit to assist steering reaction along the alignment.
• Soft Ground Conditions: The alignment passed through silty clay, posing a risk of ground instability and potential face loss during excavation.
• Accuracy Requirements: The 72-inch diameter tunnel required precise steering to ensure alignment and avoid costly deviations.
• Limited Access: The urban location of the project site restricted available space for staging equipment and operations.
• Pipe Handling: The installation of 20-foot, 72-inch diameter Permalok® steel pipe demanded careful coordination and jacking force management.
• Customized Equipment Configuration: The Akkerman SL60C MTBM was fitted with a dual- gage soft ground cutterhead and upgraded to a 72-inch OD using a specialized skin kit. This ensured optimal performance and face pressure control in soft ground.
• Belly-Pan Kit for Steering Support: A belly-pan steering kit was added to enhance machine stability and alignment control through the variable soil profile.
• High-Capacity Jacking Frame: An 800-ton jacking frame provided consistent and sufficient thrust force to advance the steel casing without overloading or causing buckling.
• Efficient Site Setup: BTrenchless managed site logistics to accommodate space constraints while maintaining efficient pipe handling and spoil removal operations.
• Precise and On-Time Completion: The 458-linear- foot drive was completed successfully with no significant deviations from the planned alignment, meeting both accuracy and schedule expectations.
• Optimized Ground Control: The use of a dual-gage cutterhead and enhanced MTBM configuration allowed for smooth excavation through silty clay without surface settlement or ground loss.
• Seamless Pipe Installation: The 72-inch Permalok® steel pipe was installed with excellent joint integrity and minimal downtime, thanks to efficient jacking force distribution and equipment coordination.
• Client Satisfaction: The collaboration between BTrenchless and Akkerman equipment ensured project success, reinforcing trust and paving the way for future trenchless solutions in the region.