偏三点弯曲岩石试件中裂纹扩展过程的数值模拟

Numerical Modeling of Crack Propagation in Rocks Under the Condition of Three-Point Bending

运用RFPA2D数值模拟方法 ,对偏三点弯曲岩石试样中裂纹的扩展路径进行了数值模拟·数值模拟结果表明 :在加载过程中裂纹有失稳扩展过程 ;当预裂纹远离试件中心线时 ,裂纹的初裂纹角θc 和峰值荷载增加 ,裂纹的失稳过程也更加明显·裂纹的扩展路径总体上遵循一定的规律 ,但由于岩石材料性质的非均匀性 。

By RFPA 2D (Rock Failure Process Analysis) Code,the path of crack propagation and its initial angle θ c of marble specimen was simulated when subjected to different mixed mode Ⅰ Ⅱ loading. The crack propagation is unstable and its path mainly follows the grain boundaries. The initial angle θ c and the peak strength increase as the pre existing crack shifts away from the midpoint of beam. The crack propagation path follows some regularity on the whole although the local path is tortuous because of the heterogeneity of rocks. The results of numerical simulation show a good agreement with those of corresponding experimental results.