Study On Failure Mechanism Of Hard And Brittle Rock Based On CT Scanning Technology

As a kind of natural material in nature,the research on the deformation,strength and failure characteristics of rock is carried out step by step along the material mechanics,elastic mechanics,plastic mechanics,fracture mechanics and damage mechanics.Rock mass is not only a kind of material,but also a complex stress-strain environment.Therefore,it is of great significance to study the mechanical properties of rock for rock mechanical engineering.CT test can accurately scan the rock specimen and obtain the internal microstructure of rock without artificial damage.At the same time,the CT number given by the CT scanner can also be used to study the mechanical properties of rock.The CT number has memory,so it can be used for data arrangement and mathematical statistics.In this paper,according to the mechanical properties of rock,marble is selected as the research object,and the mechanical test and CT scanning test of marble are designed.The mechanical properties of rock samples are analyzed through mechanical tests.Through the images and data obtained from CT test,the mechanical properties of rock are verified.In this paper,the marble of Jinping Hydropower Station is selected as the research object,and the conventional triaxial compression test and triaxial compression test of graded loading are carried out to study the stress-strain characteristics and strength parameter characteristics of marble under different loading conditions.Then CT scanning test is carried out on marble after loading failure,and the CT image of marble is obtained,and the CT image is processed by software,and the CT number of the image is also obtained.The micro structure of rock reflected by CT images is analyzed in depth.Next,the strength characteristics of rock are analyzed based on CT number.In this paper,the logical sequence of different rock CT numbers shows that the CT number has a certain memory for the strength of rock before and after loading,and carries out mathematical statistics on the CT number,and analyzes the micro element strength characteristics of rock with the variance and mean value of Weibull distribution curve.At the same time,the fractal dimension and damage variable based on CT number are calculated,and the influence of loading mode on specimen composition and damage degree are analyzed.Finally,the three-dimensional model of CT scanning image is established to restore the internal failure of rock specimen,and the failure mode of rock is analyzed.