STATISTICAL DAMAGE CONSTITUTIVE MODEL FOR SATURATED AND UNSATURATED ROCK
Wei Lide1，Xu Weiya2，Yang Chunhe1
(1Institute of Rock and Soil Mechanics，The Chinese Academy of Sciences， Wuhan 430071 China) (2Institute of Geotechnical Engineering， Hohai University， Nanjing 210098 China)
Abstract：Based on probability statistics and damage mechanics，the characteristics of failure and damage of rock are studied，and the statistical damage constitutive model of rock is developed. For stresses，only effective stresses are employed in the damage evolvement function. The residual strength property of rock can be considered in the model. Then the statistical damage constitutive model is developed for saturated and unsaturated rock based on the mixture theory. The model can reflect the segment of concave in the stress-strain curve at the initial loading phase in the uniaxial compression test of rock，and the influence of damage in compression process and fluid in the pores or void on the stress-stain curves. The presented model is verified to be reasonable and practical in comparison with the experiment data.
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2004, Vol. 23 
