Title:
Degradation of Mechanical Characteristics of Some Polymeric Mortars due to Aging
Author(s):
Manuel A. G. Silva and Zenaide C. G. Silva
Publication:
Materials Journal
Volume:
104
Issue:
4
Appears on pages(s):
337-343
Keywords:
environmental effects; polymeric mortar; stiffness degradation; strength degradation
DOI:
10.14359/18822
Date:
7/1/2007
Abstract:
The effective use and reliability of polymeric mortars require that designers and builders have a better knowledge of the temporal evolution of their mechanical properties. The study comprises tests and accelerated aging conceived to quantify the degradation of those properties and the possible interpretation of the experimental data produced. Epoxy and polyester mortars were used and coupons were subjected to: 1) dry-wet cycles; 2) thermal cycles; 3) cycles of radiation; and 4) salt fogging cycles. Compressive and flexural tests were performed. A short program to characterize diffusion of moisture in the coupons is reported and preliminary microscopic observations are presented. Degradation was higher for epoxy mortar in the cases of temperature cycles and of salt fogging cycles, both in terms of reduced ductility and of bending strength. Cycles of dry-wet environment, at fixed temperature, led to growing reductions of strength with time. Ultraviolet radiation caused essentially superficial effects and negligible reduction of mechanical strength, but a decrease of stiffnesswas detected.