STRUCTURAL ADHESIVE JOINTS FOR CIVIL ENGINEERING USE

Year 2020, Volume: 4 Issue: 4, 30 - 36, 23.10.2020

Klára V. Machalická Miroslav Vokáč

Abstract

The paper reports on an
experimental analysis focused on determining the mechanical characteristics of
two types of acrylate adhesives applied in double lap connection loaded by
shear. The study comprises two basic substrate materials often used in facades
both for cladding and for substructure – aluminum and galvanized steel. Both
materials are applied with a smooth and mechanically roughened surface to
compare adhesion in relation to laboriousness of surface preparation. Except
for blank aluminum, anodized aluminum was also used. Material and surface
treatment has a great influence not only on adhesion and hence strength of the
joint but also on failure mode, behavior and safety of a particular joint.
Moreover, every necessary surface treatment creates higher labor intensity,
higher time consumption and thus increased costs. Our results showed different
behavior of both chosen acrylate adhesives in spite of their similar chemical
base. The first acrylate, two-part structural methacrylate, showed shear
strength from 12 to 17 MPa in dependence on substrate material with shear
strain between 0.6 and 1.2. The best adhesion was observed at roughened
galvanized steel substrates. The second acrylate adhesive, two-part structural
adhesive based on acrylic double performance polymer technology (ADP), proved
shear strength from 8 to 9 MPa for aluminum substrates and less than 6 MPa for
galvanized steel substrates. ADP adhesive also showed higher shear strain
values (approx. 2.8). The experimental study proved that a choice of the
adhesive has a great influence on mechanical properties of adhesively bonded
joint as well as on adhesion to a particular substrate even in the case of the
similar chemical base of adhesives. 

Keywords

acrylate, adhesive joint, mechanical properties, metal substrate, adhesion

Supporting Institution

Czech Science Foundation

Project Number

GA18-10907S

References

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