Our UHPC grouting products are a pumpable and developed for offshore application and has been used widely in connection with structural strengthening of offshore platforms.Such UHPC grouting products have been used offshore in connection with
- Strengthening of intact tubular members
- Reinforcement of joints
- Repair of damaged members
- Pile-sleeve connections
- Strengthening of double skin sections
An example of a spectacular application of such solutions with respect to member repair is for a
member having experienced hydrostatic collapse, where the member was re-inflated and filled with ultra high performance grout. In another case our solutions were applied in connection with a pile-driving refusal (changing the intended shear key connection to a plain pipe connection). UHPC grouting high strength material was used as grout material in stead of the intended conventional grout. In the above selected cases the design strength of the members was re-established due to the extreme effect offered by high strength materials and at the same time the solutions was economically attractive.
One of the main advantages of using grouted solutions in connection with repair is the easy accommodation of geometrical irregularities. Structural components subjected to some kind of damage (from installation, impact or accident) often show some dents or imperfections. The use of ultra high performance grout in connection with repair improves the performance hereof as the UHPC grout serves not just as a filling material but as a strong structural component.
Our UHPC grouting products are suitable for casting both above and below water. Due to viscous consistency of the mixed materials there is no risk of washing out cement particles or mixing with water when cast below sea level.
The UHPC grouting products for Offshore have been developed having very low shrinkage so that
the grout and surrounding steel remains in physical contact after curing. Further, these products has been developed to show limited heat development during the hardening process eliminating the risk of thermal cracking.
If you use UHPC grouting material for oil and gas platforms as a repair material or as a material to restore or increase the static loads and also to protect against corrosion also underwater, then it should also be possible to protect subsea piplines. At present, a large gas pipeline is being laid in the Baltic Sea. The pipeline construction is encased in a thick concrete layer. That would have to be solved much better with UHPC concrete, right?
ReplyDeleteBasically, UHPC concrete is superior to standard concrete in all technical areas.
DeleteTo answer your questions, yes, it is possible to cover these pipes with UHPC concrete. Although I do not know the exact technical specification we would very probably be able to reduce the layer thickness because we are absolutely seawater resistant with UHPC. This can significantly reduce the weight. From a layer thickness of 10 mm no more water penetrates through UHPC sheathing. With an appropriate reinforcement, UHPC has very good ductile properties. UHPC has an extremely high early strength, which can optimize the production. I can increase to list but I think that shows it should be interesting for user of these pipe systems to think about UHPC solutions.