If the crazes took place, as expected considering the volume strain
measurements and the fact that the damage was recovered after the thermal treatment on the deformed specimen, they may have closed after unloading.
where [[epsilon].sub.v] is the volume strain
; [[epsilon].sub.1], [[epsilon].sub.3] are the axial strain and lateral strain, respectively; [[sigma].sub.1] is the axial stress; [[sigma].sub.3] are the confining stress; E is the elastic modulus; v is Poisson's ratio.
The conventional multifield coupling method is mainly based on the Biot consolidation equation , that is, the coupling of stress and seepage through effective stress principle and volume strain
In elastic mechanics using Poisson's ratio and axial strain to calculate volume strain
is the most common method for brittle rock.
Keywords: Coupling mechanism; Tele-seismic waves Volume strain
Water level 2011 Mw 9.1 Tohoku earthquake
Nevertheless, since these different mechanisms are accompanied by different changes in volume strain
, indications on the deformation mechanisms occurring in polymeric materials was derived from the analysis of the volumetric strain during tensile tests as previously reported in the literature [8, 26, 29-31].
where [DELTA][[epsilon].sub.P] is the equivalent plasticity, [DELTA][[mu].sub.P] is the equivalent volume strain
increment, [mathematical expression not reproducible] is the plastic strain at normal pressure P, [[epsilon].sup.f.sub.P] is the equivalent plastic strain, [[mu].sup.f.sub.P] is the equivalent volume strain
, [T.sup.*] = T/[f'.sub.c] is the maximum tensile strength of the material, T is the tensile strength of the material, and [D.sub.1] and [D.sub.2] are damage constants.
Based on the elastic half-space dislocation model (Okada, 1992; Lin and Stein, 2004; Toda et al., 2005), we calculated the coseismic static-strain change in the Fuxin well, the result of which is shown in Figure 8 and Table 1; it can be seen that the static volume strain
changes slightly during the earthquake (much smaller than that of the coseismic volume strain
), i.e., the coseismic volume-strain variation is largely induced by the dynamic stresses.
However, the volume strain
increased with the increase in shearing strain in the later stage of shearing, up to a shearing strain of 10%.
According to the conventional triaxial test results, as shown in Figures 10(a) and 10(b), the main stress difference ([sigma].sub.1] - [sigma].sub.3]) increased with the axial strain [epsilon].sub.1] before finally stabilising, but the volume strain
continued to increase.
This also reduces the sensitivity towards crazing, as the volume strain
where [G.sub.r] and [K.sub.r] are the shear modulus and bulk modulus of the rubber, [DELTA][V.sub.R] is the volume strain
in the rubber particles, G is the surface energy of the rubber phase, and the function F([lambda.sub.f])is dependent on the failure strain of the rubber under biaxial stretching conditions.