Concrete, mortar and cement based repair materials: Chloride diffusion coefficient from migration cell experiments (NT BUILD 355 – Edition 2)

Abstract

SUMMARY

The steady state chloride ion diffusion coefficient of concrete, mortar and cement based repair materials is determined by an accelerated laboratory test method. The amount of chloride vs. time passing through a porous material exposed to a constant direct voltage is measured after steady state is reached, in order to calculate a chloride diffusion coefficient.

SCOPE

This method specifies an accelerated laboratory method to determine the steady state chloride ion diffusion coefficient of porous, cement-based materials.

FIELD OF APPLICATION

The method can be used to determine the steady state chloride diffusion coefficient for concretes, mortars and cement based repair materials as a measure of their relative diffusivity after chloride binding is saturated. This diffusion coefficient cannot be compared directly with non-steady state diffusion coefficients or used in service life predictions where chlorides diffuse in a non-steady manner or are transported by absorption [3].