THE DEPTH DISTRIBUTION OF ORGANIC ADDITIVES IN MORTAR MEASURED WITH PLASMA-BASED SECONDARY NEUTRAL MASS-SPECTROMETRY

Amino alcohols (AMA) have been found to be successful in corrosion pre vention of steel-reinforced concrete [1]. However, to work effectively the amino alcohol has to be located at the interface between the conc rete and the steel rods reinforcing the stability of the building mate rial [2]. Corrosion prevention for new buildings is easy because the c orrosion inhibitor has already been added to the liquid concrete mixtu re and thus can easily reach the steel rods. With subsequent corrosion prevention measures for existing buildings, however, the problem of t ransport of the corrosion inhibitor through the solid concrete to the steel surface has to be solved first. In order to determine penetratio n, transport behavior, and transport rate, an AMA was applied to one f ace of rectangular mortar blocks used as model samples. A certain peri od of time for dwelling was given to allow the AMA to penetrate into t he mortar. Moreover, the influence of the ambient humidity during the application was investigated. The analysis of the mortar was made by S econdary Neutral Mass Spectrometry, a technique used for the first tim e for this type of material because of the easy sample preparation, sh ort analysis time, and high sensitivity.