28 июля, 2015 
Malyar The complete characterisation of an adhesive requires that its response to various load, time and environmental conditions be determined. Renton(32) says that useful data are:
(1) stress-strain response (in shear and tension) at a constant strain rate to failure
(2) cyclic stress-strain response versus the number of cycles to failure
(3) creep response
(4) combined shear and tension response
(5) the reaction of the first three items to various moisture and temperature environments.
Schematic representations of the typical response of cold-cure epoxies are depicted in Fig. 4.6. Naturally the relative importance of specific adhesive property data depends upon the application and the envisaged loading and environmental conditions that the real joint will be subjected to. Many analysts(32-34) advise that the ‘strength’ of the adhesive equilibrated with the ‘worst-case’ environment is the key to effective design. This implies laboratory tests conducted at high temperatures on specimens pre-equilibrated with high levels of water vapour or liquid water. For the application of adhesives to steel bridges in the USA, Albrecht et al. (34) selected a test environment of 49 °С and 90% r. h.
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