To prove the convergence of DSCM for the problem (5), we first give the following lemmas.
If the analytical solution of the problem (5) y(t) [member of] [C.sup.4][0, T], the spline functions S(t, h) and [bar.S](t, h) defined as (9) and (24) on the same grids are the numerical solutions of the problem (5) obtained by DSCM and ISCM, respectively; then we have the following conclusions.
(ii) Assume that yS(t, h), zS(t, h) and y[bar.S](t, h), z[bar.S](t, h) are the numerical solutions obtained by DSCM and ISCM for the problem
Moreover, the digital speckle correlation method (DSCM) measurement was conducted to analyze the deformation characteristics before peak stress.
Figure 7 shows the horizontal and vertical deformation fields of intact specimens and layer-crack specimens before peak stress from the DSCM measurement.
In general, the DSCM results reveal that under the same loading and lithology conditions, if the number of layer-crack plate increases, the instability probability will be enhanced, that is, the occurrence risk of rock bursts increases.
Digital Speckle Correlation Method (DSCM) is employed in this research for real-time capturing and accurate processing of the speckle images on the specimen surface.
As the quality of these speckles is critical for the final accuracy of the DSCM results, the statistical distribution of gray level was employed to evaluate it.
Gathering uniaxial creep compressive test and DSCM is a valid approach to observe rock failure evolution in creep.