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Drucker-Prager屈服准则中压力相关系数α和黏聚剪切强度k的实测结果少有报道。根据同一组致密砂岩三轴压缩试验,同时测试Mohr-Coulomb准则中的内摩擦角φ和黏聚力c以及Drucker-Prager准则中的压力相关系数α和黏聚剪切强度k。测试结果显示,描述岩石内摩擦性质的参数φ和α随着塑性变形的增长而增长,但是增长速率逐渐减小;描述岩石胶结性质的参数c和k在岩石初始屈服后会先上升至峰值,然后随着塑性变形的增长从峰值逐渐下降。同时,从5种常用的Mohr-Coulomb准则与Drucker-Prager准则转换关系中,通过同一组三轴压缩试验结果寻找到吻合程度最高的换算关系。Drucker-Prager材料强度参数的变化将来可应用到岩土类材料的数值计算中来模拟材料的强化和软化性质,同时也可以为Mohr-Coulomb准则参数与Drucker-Prager准则参数转换提供一定参考。
Drucker-Prager yield criterion in the pressure coefficient α and cohesive shear strength k of the measured results rarely reported. According to the same set of tight sandstone triaxial compression tests, the internal friction angle φ and cohesion c in the Mohr-Coulomb criterion and the pressure correlation coefficient α and the cohesive shear strength k in the Drucker-Prager criterion are also tested. The results show that the parameters φ and α, which describe the internal frictional properties of the rock, increase with the plastic deformation, but the growth rate decreases gradually. The parameters c and k, which describe the rock cementation properties, first rise to the peak value after the initial yielding, Then gradually decreases from the peak as the plastic deformation increases. At the same time, from the five commonly used Mohr-Coulomb criteria and Drucker-Prager criteria conversion relationship, through the same set of triaxial compression test results to find the most consistent conversion. Drucker-Prager material strength parameters in the future can be applied to the numerical calculation of geotechnical materials to simulate the strengthening and softening properties of materials, but also can provide reference for the conversion of Mohr-Coulomb criterion parameters and Drucker-Prager criterion parameters.