Dynamic Crack Propagating Mechanism of Rock Materials Based on Different Weighted Functions

• Main Authors: Huijun Wu, Jing Zhao, Zhongchang Wang, Xunguo Zhu, Deshen Zhao
• Format: Article
• Language: English
• Published: IFSA Publishing, S.L. 2013-11-01
• Series: Sensors & Transducers
• Subjects: Weight function; Intrinsic characteristic length scale; Crack; Stress intensity factor; Non-local theory.
• Online Access: http://www.sensorsportal.com/HTML/DIGEST/november_2013/PDF_vol_159/P_1545.pdf

The singularity at the crack tip can be smoothed by the non-local theory based on different types of weighted functions. In the paper, the characteristics of different types of the weighted functions and their effects on non-local model are analyzed. The effects of the stress intensity factor KI and KII on the all components of stress-strain field in the neighborhood of the crack tip are analyzed by different types of the weighted functions. It is shown that the larger intrinsic characteristic length scale is, the more significant the reduction of non-local strain with respect to the local strain predicted conventionally will be. The size of non-local strain field with the bell-shaped weighted functions is larger than that obtained by either Green's or Gaussian weighted functions. The non-local normal stress-strain components depends on the stress intensity factor KI and KII, the circumferential stress is related to the stress intensity factor KI. The effect of stress intensity factor KI on non-local radial stress is positive while the effect of KII is negative. The non-local circumferential stress is related only to the stress intensity factor KII while the non-local shear stress is related only to the stress intensity factor KI. The larger the intrinsic characteristic scale is, the more significant the reduction of non-local strain with respect to the local strain predicted conventionally will be.