Selection of optimum specimen shape for compression tests on brittle materials. II

Conclusions

• 1. Use of the finite-element method made it possible to evaluate features of the stress-strain state of composite specimens and to establish the principle structural parameters and technological factors affecting stress-strain state and supporting capacity.

• 2. A theoretical basis was found for a test method for brittle materials under uniaxial compression in holders, and the effect of each selected parameter on the stress-strain state of a brittle rod was studied over a wide range.

• 3. The possibility of solving the choice of optimum composite specimen shape by a numerical method was considered.

  From the stress state analysis, recommendations were made for the geometric shape of a composite specimen with data for the ratios of brittle material and metal holder elastic constants, and also glued joints,

• 4. Fulfillment of these recommendations makes it possible to increase supporting capacity and to decrease scatter of values for brittle material composite specimens.

• 5. The prospects for using the finite-element method of evaluating composite structures of brittle materials was noted.