controlled permeability formwork

[materialsengineering]

Is it any way possible that marine concrete formed by means of "controlled permeability formwork" can be durable without additional protection e.g., from silane treatment, etc.? How durable is such concrete, has there been any documented research work in this respect?

 

[Formtex]

We are the producers of a Controlled Permeability Formwork (CPF) liner called Formtex.
You do not write what brand of CPF has been used, but generally concrete produced with CPF is very durable and does not need silane treatment or coatings of any sort. What the CPF liner does is to drain out the water in the first approx. 20mm of cover concrete. This increases the density of the concrete cover considerably as the water/cement ratio is lowered. If you would like more information, please see

http://www.formtex.dk.

On that web-site is also my contact information, so please do not hesitate to contact me if i can do anything further.
Regards
Morten Sorensen

 

[Formtex]

It is always a question of the level of durability, but a surface produced with Controlled Permeability Formwork is very durable, and certainly competitive to silane and other surface treatments. Furthermore, CPF improves the actual concrete instead of taking measures to improve poor concrete. CPF is very thoroughly documented. CIRIA and the concrete society have made a report (CIRIA C511 - ISBN 0 86017 511 1) in 2000 that documents the effect and improvements achieved with CPF. It has become a little out of date with respect to the liners available and the properties of these specific liners, but the results that are presented are of course still valid. Furthermore there are some reports available online at

http://www.formtex.dk

under documentation=>Technical reports. Should you be interested in some of the reports not available online, please let me know and I will send a copy to you. I also know that our competitor Zemdrain has reports on CPF.
Actually we have just delivered the last shipment for a very large marine structure. In this case the concrete was cast using CPF and then treated with Silane. This combination produced an extremely durable surface, and the results from this project are very impressive. I of course have the results, and I would be happy to share them with you.
I hope this answers your questions, if not please let me know.
Regards
Morten Sorensen