I hoped you would say something like that. In a way i see you confident that the actual methods used in marine concrete engineering are “sufficiently good”
So what we have at hand, can serve as foundation of a floating city - in spite of the pictures of concrete spalling caused by rusting rebar that @NickGri posted.
In a way i do not want this to become another “versus debate” where it comes to a polarization of the benefits of steel rebar versus the benefit of basalt rebar.
I think we all are in consensus that the "vulnerable component of the “composite material concrete” is in fact the rebar.
We are also aware that there are horrible examples of concrete falling apart due to rebar rusting.
To be fair it needs to be said that there are also “surprising examples of non rusting rebar in marine ambient for many decades”.
It is no secret that the North Sea concrete based floating oil infrastructure, far from falling apart after a few decades, just was upgraded in “service life expectancy” and surprisingly little damage was found after decades of exposure by independent surveyors.
It is also known that concrete ship SS Peralta built 1921 and on a cero maintenance shedule since then is still floating.
So i would like to invite to a kind of consensus that the horrible spalling pictures correspond rather to a “incompetent builder” getting the mix wrong and failing to apply “good concrete practice” than to a universal “non fitness of steel reinforced structures for the marine ambient”.
Having said that it must also be mentioned that the traditional marine concrete engineering is vulnerable to errors of the contractor resulting in desasterous service life reductions.
So the question if it is wise and neccessary to look into alternatives to steel rebar is still on the table - altough “existing structures have shown a good overall performance” over several decades.
So nobody expects the structures built by @aliduman and @Kerim_Tapkan to have a service life of less than 100 years what makes them compareable to any land based building.
@NickGri | @aliduman | @Kerim_Tapkan | @Matias |
If the “expert panel” is still with me on that consensus the interresting questions that are on the table are:
• If we have technology at hand to build floating cities where is the bottleneck that avoids that this is happening ?
• Is it the cost factor ?
• What are the markets floating real estate would have to compete with ?
any comments on that ?
Pieces of the North Sea Oil Infrastructure | Ekofisk | Marine Concrete Engineering |
Tubular marine concrete structure | Troll A | 303m deep underwater | decades of deterioration free service | 1m wall thickness | 24 m tube diameter | what is out there already | works surprisingly fine |