Evaluation of the gain of durability provided by the use of a controlled permeability formliner for concrete in maritime site

Benoit THAUVIN – CETE Ouest, Nicolas Rouxel, Stéphane Pasquiet - CETMEF

Abstract

The purpose of a controlled permeability formliner is to improve the characteristics of concrete skin. In practice, the method is implemented on the shuttering prior to the pouring of concrete. By increasing the surface compactness of concrete within drainage of excess water, this process should improve the durability of reinforced concrete relative to the reinforcement corrosion. The use of such a process would therefore serve to increase the service life of reinforced concrete marine structures by improving the properties of concrete and slowing skin chloride penetration causing corrosion.
This study, conducted at the request of CETMEF, aims to qualify and quantify the gain of sustainability provided by the use of a controlled permeability formliner. It is based on the evaluation of durability indicators and monitoring parameters. The experiment is based on the achievement of characterization tests on the tests specimens made using a a controlled permeability formliner.
A device called a “accelerated aging”  by cycle of artificial tidal in a pool has been designed to accelerate the penetration of chlorides and thus assess the impact of controlled permeability formliner in the process of chloride penetration. The experiment lasted 454 days. The tidal system has accelerated the phenomenon of chloride penetration. At the end of the experiment, we observed lower concentrations of chloride in the concrete cover of trials carried out with controlled permeability formliner. The study also shows that the use of such a process has a significant impact on durability indicators and monitoring parameters.
The overall results suggest that the impact of this process on the properties of concrete concern the concrete cover to a depth between 1 and 2 cm.