Red sandstone is widely distributed in China

and its disintegration is very significant due to changes in water content. The red sandstone samples from Zhuzhou area of Hunan Province were used to conduct laboratory static and disturbed disintegration tests. Then

an evolution model of gradation curve of particle disintegration of red sandstone was established based on the Weibull distribution

and the model parameters λ and k were analyzed

the value and change rate of the two parameters reflect the evolutionary process of particle disintegration and breakage of red sandstone. Moreover

on the basis of established model

the calculation formula of the relative disintegration ratio was obtained

and the correctness of the formula was verified. Furthermore

according to the test results and the values of model calculation

the similarities and differences between the slaking durability index and the disintegration ratio

and the effects of different test methods on the test results were discussed. Finally

the feasibility of application of Weibull distribution model to the evolution of rock particle disintegration is verified based on the existing researches.