Acta Mechanica Solida Sinica

, Volume 30, Issue 4, pp 335–344 | Cite as

Assumed stress quasi-conforming triangular element for couple stress theory

  • Changsheng Wang
  • Xiangkui Zhang
  • Ping Hu


In this paper, a 3-node triangular element for couple stress theory is proposed based on the assumed stress quasi-conforming method. The formulation starts from polynomial approximation of stresses. Then the stress-function matrix is treated as the weighted function to weaken the strain-displacement equations. Finally, the string-net functions are introduced to calculate strain integration and the stress smooth technique is adopted to improve the stress accuracy. Numerical results show that the proposed new model can pass the C0 1 patch test with excellent precision, does not exhibit extra zero energy modes and can capture the scale effects of microstructure.


Quasi-conforming Couple stress theory Fundamental analytical solutions 


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Copyright information

© The Chinese Society of Theoretical and Applied Mechanics and Technology 2017

Authors and Affiliations

  1. 1.School of Automotive Engineering, State Key Laboratory of Structural Analysis for Industrial EquipmentDalian University of TechnologyDalianPeople’s Republic of China

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