The Joint Rock Fracture Extension Study Based On The Finite Element Method

Rock is a kind of essence of non-uniform material, often with a large n rer of joint defects such as cracks and pores, under the action of external load, the defects cau by rock mass crack initiation extension and penetration, makes rock mass stiffness, strength is duced, and even cause engineering disasters,such as rock burst,collapse in rock engineering, at deep fracture in the foundation engineering.Therefore, it has been a subject of intensive resear on the initiation, propagation, coalescence and interaction of cracks, it is of important sciem and engineering significance to study on failure behavior of rock containin three-dimensional pre-existing crack.In this thesis, based on joint rock compressive strength test and three point bending test, using ABAQUS software to solve different Angle crack distribution under different loading conditions to research, mainly includes:(1)Make a review of the latest advances in research on the initiation,propagation, coalescence and interaction mechanism of cracks.(2)Through experiment to get the basic mechanical parameters of rock samples, and thus determining the numerical simulation of basic material mechanics parameters.(3)Rock damage under different peak load makes influence and get the crack propagation process based on the three point bending test.(4)By three point bending test research different span length of crack and the influence of different loading rate on the stress intensity factor.(5)To study the different Angle of the single crack| sample destruction, get different Angle influence on rock breaking strength of crack Angle crack failure mode and mechanism of crack extension.(6)Simulation study of more than offset crack and crack, crack extension process and failure mechanism.