Flathouse Quay Structural Capacity Assessment

Portico required to know the condition of the quay deck, especially the area associated with the temporary storage of aggregates. The requirements were to deliver a detailed report containing:



• Summary of testing undertaken.
• Geotechnical data and analysis findings.
• A plan view of the survey area highlighting the location of any identified issues.
• A clear statement of the safe ground bearing capacity.
• Any remedial recommendations.
  

Removing the masts from the world's oldest commissioned warship presented a unique combination of engineering, operational and heritage risks. The project involved lifting irreplaceable historic structures using a 750-tonne crane and specialist lifting equipment, with all works carried out overnight to maintain a controlled and safe working environment. 

The client needed independent engineering assurance to validate the lifting strategy, manage project risks and support the safe execution of this highly complex operation.

Attis undertook a comprehensive programme of non-intrusive testing and engineering assessment across the full length of the quay. The investigation combined deck, seismic and pile testing methodologies.

The deck testing methodology provided the ground pressure capacities, with the localized and more penetrative seismic test providing a clear indication of the deeper ground composition. These results were combined and represented as a single heat map identifying the ground loading results in tonnes per square metre.

The assessment confirmed the sections of the berth that are capable of supporting heavy port vehicles and cargo handling activities, as well as identifying specific areas requiring remediation.

The results were presented in the order of:



• Immediate limitations of operation.
• Potential mitigations to reduce the associated risks.
• Prioritisation of remedial actions.
• Suggested traffic routing for heavy vehicles and dockside cranes.
  

"Changes to the way we use one of the berths at the port meant we really needed to understand its capacity. Portico Shipping is a busy port and interference to operations can be very costly. Attis were able to work in and around our berthing operations without causing any disruption, a fact our operational team really appreciated. The results of the testing provided us with valuable information about where the real issues are, and we can use this going forward to make well informed decisions on remedial works."