When determining stress states by the hole-drilling method, it is necessary to take into account the experiment performance accuracy. The drilled holes eccentricity appears as a frequent imperfection, which influences essentially the reliability of their stress state assessment. This paper presents the hole-drilling measurement method corresponding to the E 837 standard method, but, at the same time, it is more universal. This method transforms the full stress tensor of the drilled hole position by the regression coefficients and describes the state of strains released in the hole surrounding, based on the hole center distance and its depth. The regress coefficients are not defined in the method concretely for the rosette but they are universal both for the isotropic Hooke’s materials and for the other measuring elements. The method defines the way for the processing of the released strains measured with a defined measuring element and involves naturally the influence of the drilled hole eccentricity and so it is possible, in the hole-drilling method, to apply measuring elements more simply, without determining their specified regression coefficients. Modification of Decomposition theory for semiconductor hole drilling rosette with a greater sensitivity is advantageous.

When determining stress states by the hole-drilling method, it is necessary to take into account the experiment performance accuracy. The drilled holes eccentricity appears as a frequent imperfection, which influences essentially the reliability of their stress state assessment. This paper presents the hole-drilling measurement method corresponding to the E 837 standard method, but, at the same time, it is more universal. This method transforms the full stress tensor of the drilled hole position by the regression coefficients and describes the state of strains released in the hole surrounding, based on the hole center distance and its depth. The regress coefficients are not defined in the method concretely for the rosette but they are universal both for the isotropic Hooke's materials and for the other measuring elements. The method defines the way for the processing of the released strains measured with a defined measuring element and involves naturally the influence of the drilled hole eccentricity and so it is possible, in the hole-drilling method, to apply measuring elements more simply, without determining their specified regression coefficients.

The methodology, used for determining the structure material elastic constants, is based on mechanical tests, being mostly tensile ones, applied on partially loaded specimens. There be can glass materials used as different alloy elements, therefore the glass elastic constants can vary considerably. However, using classic glass tensile specimens for tensile tests can be problematic, due to their production and implementation of tensile tests. Experimental methods for identifying the glass Young's modulus of elasticity and Poisson's ratio are based on a comparison of the displacement measurements applied on the glass beam, or curved rod, samples, combined with their displacements calculation.

The hole drilling method used for the stress state identification is currently standardized by the E 837 international standard. It is based on relaxation of the residual stress in vicinity of the drilled hole. Relaxation of the residual stress relieves deformations which are measured with strain gage rosette. However, using the theory E 837 does not correct the influence of the experimental hole imperfections (eccentricity, roundness, perpendicularity) on this experimental method accuracy. This article analyzes the extent of errors that affect these imperfections.

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