Air permeability of hardener-free epoxy-modified mortars as repair materials

Abstract

The air permeability of patch materials or cover concrete plays an important role in the durability of repair work for deteriorated reinforced concrete structures because it controls the rate of penetration of air with moisture. The purpose of this study is to investigate the air permeability of the hardener-free epoxy-modified mortars by applying a non-destructive in-situ testing method specified in the State-of-the-Art Report of RILEM Technical Committee on Non-Destructive Evaluation of the Penetrability and Thickness of Concrete Cover. Hardener-free epoxy-modified mortars using a bisphenol A-type epoxy resin without any hardener are prepared with polymer-cement ratios (epoxy-cement ratios) of 0, 5, 10, 15 and 20%, and tested for moisture content, air permeability and strength after a 28-d dry curing.