Back in April (See news article: “Who you Gonna Call“), Jenkins Marine was called to complete emergency repairs at a section of Poole Quay. Following emergency piling works to stabilise the failed quay wall at a residential/marina development, further detailed design and engineering works have been completed to produce a design for a more permanent repair.
Workboat ‘Avon‘ was deployed again to complete the initial piling work to install 20no , 15m long, 508mm outside diameter tubular steel piles on site. The piles were loaded from Jenkins Marine’s quay in Poole into 32m long hopper barge ‘Hurst‘ to optimise the efficiency of the piling operation; enabling the piling barge to pick up piles as needed without having to leave site and load more piles each day.
Piling progressed well on site using a 4.5t resonance free variable moment vibratory piling hammer. Unfortunately, the hard clay ground conditions meant that the piles hit refusal before they could achieve full penetration. After a few phone calls and much discussion, the decision was made to try a larger piling hammer. A much larger 10t Vibro hammer was sourced and delivered without delay, but a larger crane was required to handle it… Multi-role workboat ‘STOUR‘ was mobilised with Jenkins’ 50t lattice boom crawler crane and successfully drove the piles to the design depth, much to the client’s satisfaction, and not without a lot of vibration!
The piles were driven against custom made steel brackets bolted to the concrete wall. The Jenkins Marine team then welded the new piles to the brackets, and capped the piles. Works are due to continue with the design and installation of a further section of sheet pile wall on site, followed by the replacement of the marina pontoons.