Page 37: of Offshore Engineer Magazine (Mar/Apr 2015)

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de-bonding within connections, including ultra-high strength grouts, to

EPIC provides high volume stability be mixed and pumped at rates exceed- •

Rapid strength build up to sup- ing 10cu m/hr. At the DONG Energy/ port increased installation rates ScottishPower Renewables West of and to guarantee stable structures Duddon Sands Offshore Wind project, at an early age reducing the risks in the Irish Sea, this resulted in a time from cyclic loading. saving of two hours per foundation. •

Low heat of hydration, eliminat- For projects the size of West of Duddon ing the risk of thermal cracking. Sands (108 turbines) this kind of saving

Signifcant cost savings can be can amount to considerable savings in achieved with the availability of the vessel’s critical path over the dura- materials, such as MasterFlow tion of the project.

9500, which can provide adequate However, the real challenge has been curing rates at low temperatures. to develop a material that, although a

The faster a material cures, the blend of more than one component, shorter the weather window delivers a consistent mix that can be used required to complete the grouting with a pressurized silo and RJM mixer.

operations. Even at low tempera-

Ongoing development tures, MasterFlow 9500 develops signifcant strength early on and FoundOcean collaborated with chemicals as such can be applied at lower company BASF to develop the BASF temperatures compared to similar MasterFlow 9800, which launched in products. This makes it suitable February. The material has been specif- for use in colder periods and cally developed to meet the demands means it can make use of shorter, of the offshore wind industry, where

FoundOcean’s RJM (recirculating jet mixer). and more frequent, weather improvements in productivity and eff- windows. As a result, there is ciency are key for the long term sustain- less chance of a project being ability of the industry. delayed due to adverse tempera- This new material offers the advantage tures frequently experienced in of being signifcantly faster, as well as the spring and autumn months. cleaner and safer, than its predecessors.

This means vessel productivity Since the material is able to be used in can be increased and installation silos, vessel resupply is more effcient. times kept to a minimum. Thanks Moreover, the FoundOcean RJM may be to its impressive properties, used to provide mixing and pumping

MasterFlow 9500 is the frst prod- rates close to 20cu m/hr. As previously uct of its kind to receive the latest mentioned, RJM spreads are enclosed

The West of Duddon Sands ofshore wind farm

DNV GL certifcation for offshore systems, which essentially eliminates the saw 108 turbines installed. concrete structures. escape of cement dust into the environ- hand, have numerous applications in However, ultra-high strength materi- ment. Moreover, RJMs require minimal situations that require 28-day characteris- als do not easily lend themselves to the support to carry out the grouting opera- tic strengths of 100MPa or higher. These high delivery rates of ordinary Portland tions, compared to the labor intensive types of grout are synonymous with cement. Materials that can consistently pan mixers. In essence, the material is set monopile transition pieces for offshore provide strengths above 70MPa include to revolutionize the client’s choice and

Oil and gas wind foundations. Ultra-high strength additives and aggregates which, due to expectations with regards to delivery and

Foundation design for greenfeld oil and grouts are occasionally used in life their non-homogenous structure, must resupply of grouting materials. gas structures very rarely demand ultra- extension projects where they are used be batch mixed to ensure the correct

Jim Bell began his strong bonds; ordinary Portland cement to replace OPC in member strengthening blend of all the components is achieved. engineering career in (OPC) is therefore most often used, provid- projects and in grouted repair clamps. Consequently, these materials are stored heavy civil engineer- ing a connection that is more than ade- Ultra-high strength grouts have in bulk bags, which must be batch loaded ing and highway quate. OPC is suitable for projects specify- enhanced properties over OPC, which have into the pans for mixing, unlike the RJM’s, construction at ing strengths of between 40 and 70MPa; for been engineered into the product to allow which have the advantage of being a

Wimpey Construction example, in main leg or skirt pile grouting for the dynamic loads and choice of foun- closed and autonomous system. Moreover, of platforms or in the flling FoundOcean’s dation. For grouted connections in offshore

Group. He then the bags must be transported in 20ft con- fabric formworks. This tried and tested wind, FoundOcean primarily uses BASF moved to the offshore tainers, rather than 100-tonne silos, taking practice of offshore grouting with OPC is MasterFlow 9500, for which it is a licensed division of Wimpey Laboratories. up more valuable deck space. carried out by FoundOcean using its recir- applicator. MasterFlow 9500, in addition

Bell took the role of Managing Director at

FoundOcean has developed the super culating jet mixer (RJM), which achieves to ultra-high strength, offers a number of

FoundOcean in 2005, where he has pan mixer, designed to help eliminate implemented major strategic changes mixing rates of up to 30cu m/hr. pioneering properties, including; grouting as a potential bottleneck when

Zero autogenous shrinkage, a factor mixing and pumping ultra-high strength • resulting in a signifcant expansion of the

Ofshore wind that has been shown to cause cracking grouts offshore. The super pan mixer was business. Bell holds a degree in civil

Ultra-high strength grouts, on the other in high strength concrete structures and the frst to enable batch mixed materials, engineering from London’s City University.

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