Applicability Analysis of Hyperbolic Drucker-Prager Strength Criterion for TATB-based PBX

To accurately establish the strength criterion of TATB-based PBX materials, the strength data under different confining pressures(0-10 MPa)and different temperatures(22.5, 35, 50℃)were obtained through the self-developed active confining pressure tester. Based on the experimental data of uniaxial tension, uniaxial compression and confining pressure compression, traditional Drucker-Prager(D-P) and hyperbolic D-P strength criteria were used to establish the strength model of TATB-based PBX at different temperatures, and the prediction accuracy for experimental strength data was analyzed. Results show that the maximum relative errors of the hyperbolic D-P strength criterion at 22.5, 35℃ and 50℃ are 2.41%, 3.46% and 5.22%, respectively, and the root mean square errors are 0.42, 0.38 MPa, and 0.44 MPa, respectively, which are better than those of the traditional D-P strength criterion. The relative errors for the prediction of indirect triaxial tensile and compressive failure stress are 4.93% and 12.14% respectively and they are superior to the traditional D-P, Mohr-Column, twin shear and uniaxial strength criteria. The hyperbolic D-P strength criterion of considering the influence of middle principal stress and being everywhere regular, can accurately predict the strength characteristics of TATB-based PBX materials at different temperatures. © 2019, Editorial Board of Chinese Journal of Energetic Materials. All right reserved.