Mechanical properties of lime-based mortars reinforced with plasma treated glass fibers

Abstract

The interface interaction between reinforcing glass fibers and a brittle silicate matrix is the key parameter influencing mechanical behavior of lime-based fiber-reinforced mortars. Most glass fibers are industrially sized by a smooth layer of polymer-based coating causing poor adhesion between fibers and the matrix. This study examined oxygen plasma etching of glass fibers sized by aminosilane. Modified fibers were observed using SEM microscopy to reveal changes in their morphologies. Chemical changes were detected using contact angle measurement with samples wetted by water. To reveal the interaction between fibers and the matrix, mechanical destructive tests were conducted on prismatic fiber-reinforced mortar samples. Sized fiber surfaces were slightly roughened and activated. Loading tests revealed that bending and the compressive strength of lime-based mortars reinforced with treated fibers performed more poorly than those with reference fibers.