Study on sandstone failure criterion based on energy principle

LIU Wenbo; ZHANG Shuguang; ZHENG Dawei; ZHAO Hongda

doi:10.13199/j.cnki.cst.2017.12.013

Abstract：In order to analyze the different pore water pressure affected to the stress and strain relationship of the sandstone,an MTS812.03 rock test device was applied to the conventional triaxial compression test on the saturated sandstone under different confined pressure and pore water pressure.In combination with the energy principle,the sandstone failure criterion suitable to the water and rock coupling was deduced and was applied to the numerical simulation for the analysis and verification.The results showed that due to the rock loading process was an energy accumulation and releasing process,the failure criterion deduced with the energy principle could well reflect the real condition of the rock failure.The introduction of the pore water pressure influence coefficient could make up the defect due to the software could not simulate the cracking expansion caused by the water pressure.Finally,the comparison analysis showed that the calculation value of the energy failure criterion would be 5％ smaller than the actual value and the error value of the Drucker-Prager and Hoek-Brown Criterions would be 35.34％ and 37.11％ in the max.Therefore,based on the energy principle criterion,the FLAC3D software could be applied to deduce the rock failure criterion being correct and rational under the water and rock coupling role.