The Establishment Of Rock Damage Constitutive Model And The Application In The Calculation Of Surrounding Rock Stability

The constitutive relation of rock is importantly helpful to geotechnical enginee r ing activities.This paper establishes damage constitutive models of rock with the help of micro damage mechanics theory,macroscopic damage mechanics theory,statistica l strength theory,species growth model,statistical function and continuous damage theory;in the process of establishing the damage constitutive model,it may be divided into two types:Firstly,this paper introduces probability distribution suited by the strength of micro elements(logarithmic normal distribution,and it adopts the stress combinat io n form of M-C criterion to establish damage evolution model based on statistic strength theory.At the same time,this paper establishes continuous damage constitutive models based on statistic strength theory with continuous damage mechanic theory.Secondly,due to the relationship between damage growth and species growth and the stress combination form of M-C criterion,this paper establishes damage evolutio n model based on Logistic model.Meanwhile,it also establishes continuous damage constitutive models based on Logistic model with continuous damage mechanic theory.This paper calculates parameters of rock damage constitutive models by least square method,peak point method and inversion method;meanwhile,it tests the applicability of rock damage constitutive equation under uniaxial and three axial compression conditions,and with the introduction of residual strength,this paper also proposes a new rock damage constitutive model under three axial compression condition.This paper tests rock damage constitutive models under uniaxial compression conditions,and according to fitting effect,it can analyses the precision and conclude the classification that these models suit rock;moreover,it also tests rock damage constitutive models under three axial compression condition,analyzing the precision with the help of fitting effect.With the programming of damage constitutive models proposed by this paper,secondary developing FLAC^3D analyzes the stability of surrounding rock.