Research On The Constitutive Relationship Of Rock Damage Based On Energy Dissipation Theory

In this study,by analyzing different types of energy-based damage constitutive models,a brand-new damage relationship considering energy dissipation specifications was determined.The model is verified by three methods:uniaxial compression test,uniaxial cyclic loading and unloading,and triaxial loading test.The uniaxial cyclic loading-unloading test is divided into initial stage loading and unloading,intermediate stage loading and unloading,and final stage loading and unloading.Three test stages;select the triaxial loading test data with confining pressures of 5MPa,10MPa,20MPa and 30MPa.According to the completed uniaxial loading,uniaxial loading-unloading test fitting results,and triaxial test data fitting results comparison,and in-depth exploration of the test parameters,establish the true meaning of the parameters ? and ?.Research indicates:(1)This paper studies the evolution relationship of rock damage and derives a rock constitutive model based on the energy dissipation theory,which will provide a new perspective for the study of rock material damage,and is conducive to further research on the damage constitutive model.(2)In the process of uniaxial compression,according to the results of the unidirectional force loading test,it is determined that the fitting correction parameter is 0.99.The fitting effect is better,which proves the rationality of the constitutive relationship;When single-axis cyclic loading-unloading,comparing the result data of each loading-unloading stage and conducting reliability exploration,it also shows the rationality of the constitutive relationship.(3)In the axial loading test,through the fitting of the test data under different confining pressures to the constitutive model,the fitting correction coefficient is about 0.95 when the confining pressure is 5Mpa,and the other confining pressures are all above 0.97,which is sufficient to explain that under triaxial loading The applicability of the model is good.The fitting parameters ? and ? are expressed by the confining pressure and the strain of the specimen,and the proposed constitutive model is further revised.The revised rock damage constitutive model parameters will further simplify the revised model.The model fitting parameters Further reduction,calculation is more convenient.(4)Comparing the results of uniaxial cyclic loading and unloading and triaxial loading,it is believed that the parameter ? is related to the degree of compaction of the rock material;and there is a connection between the parameter ? and the material characteristics,and the parameter ? may be related to other factors other than the internal discontinuous structure of the material,Including sample moisture content,temperature,etc.,its true physical significance needs further research and analysis.Figure[36]Table[3]Reference[62]...