KSME Journal

, 3:103 | Cite as

Finite crack propagation in a micropolar elastic solid

  • Seog Young Han
  • M. N. L. Narasimhan
  • T. C. Kennedy


The dynamic propagation of a finite crack under mode-1 loading in a micropolar elastic solid is investigated. By using an integral transform method, a pair of two-dimensional singular integral equations governing stress and couple stress is formulated in terms of displacement transverse to the crack, macro and micro rotations, and microinertia. These equations are solved numerically, and solutions for dynamic stress intensity and couple stress intensity factors are obtained by utilizing the values of the strengths of the square root singularities in macrorotation and the gradient of microrotation at the crack tips. The motion of the crack tips and the load on the crack surface are not prescribed in the formulation of the problem. Therefore, the method of solution is applicable to nonuniform rates of propagation of a crack under an arbitrary time-dependent load on the crack surface. As an example, the diffraction of a micropolar dilatational wave by a stationary crack is considered. The behavior of the microrotation field and the dynamic couple stress intensity factor, influenced by microinertia, in addition to the dynamic stress intensity factor, are examined. The classical elasticity solution for the corresponding problem arises as a special case when the micropolar moduli are dropped from the present solution.

Key Words

Micropolar, Microcontinuum Stress Intensity Factor Couple Stress Couple Stress Intensity Factor Microrotation 


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Copyright information

© The Korean Society of Mechanical Engineers (KSME) 1989

Authors and Affiliations

  • Seog Young Han
    • 1
  • M. N. L. Narasimhan
    • 2
  • T. C. Kennedy
    • 2
  1. 1.Rolling DepartmentResearch Institute of Industrial Science and TechnologyPohangKorea
  2. 2.Oregon State Univ.USA

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