ISSN:
1573-0956
Keywords:
Constitutive law
;
crustal rocks
;
clay analogy
;
thermoplasticity
;
water pressure
;
subduction
Source:
Springer Online Journal Archives 1860-2000
Topics:
Geosciences
,
Physics
Notes:
Abstract Thermo-mechanical behaviour of rocks shows phenomenological similarities to that of clays. A visible decrease of strength and an increase in ductility at elevated temperatures are observed in drained conditions. In undrained conditions the strength decrease is even more dramatic and the ductile behaviour may turn into the brittle one, if a sufficient amount of water is present in the pores at the start of the process, or it is being released during heating by the decomposition of hydrous minerals. Applying a thermo-plasticity theory, major macroscopical characteristics of behaviour may be modelled. According to this theory, the elastic domain is postulated as temperature dependent, shrinking with temperature; heating may result in expansive or compactive volumetric irreversible strain depending on the confining stress. This theory is applied to the modelling of heat effects on local changes of permeability around a cylindrical nuclear waste container disposed off in deep clays, and in the numerical simulation of a mechanism initiating deep earthquakes.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00690178
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