Aubin had been instructed by the client to carry out initial laboratory analysis work for the grouting system to be used in the construction phase of an offshore wind farm in Scotland.
Over 100 foundation structures will be deployed in this wind farm, and strength development has a significant impact on vessel and equipment operational time and therefore project schedule and costs.
The challenge was to design a slurry to meet certain specification criteria and offer an overview of grouting behaviours at certain stages in the curing process.
Key specification criteria included;
Due to the low strength characteristics required and the focus on workability, Aubin used expertise from the oil and gas sector to use American Petroleum Institute testing methods (API RP 10B) to conduct workability/viscosity evaluation of the grout, as well as ultrasonic compressive strength characterisation (rather than cube crushing).
By utilising an ultrasonic testing method, a design was qualified using ordinary Portland cement which met all key criteria requirements including the required 7 day strength specification. This design was submitted by the client, who subsequently won the contract to deploy grout in this wind farm. Aubin has been retained for the subsequent project optimisation design and testing.
Aubin’s third party grout addmix design and qualification capabilities offers our customers an additional level of authority to support technical responses to their end client and the offshore wind industry as a whole.