A generalized plane strain micromechanical model is developed to predict the stress
and strain fields and overall elastic properties of a unidirectional fiber-reinforced
composite subjected to various axial and transverse normal loading conditions using
a least-squares-based differential quadrature element method (DQEM). The
representative volume element (RVE) of the composite consists of a quarter
of the fiber surrounded by matrix to represent the real composite with a
repeating square array of fibers. The cubic serendipity shape functions are used
to convert the solution domain to a proper rectangular domain and the
new versions of the governing equations and boundary conditions are also
derived. The fully bonded fiber-matrix interface condition is considered and
the displacement continuity and traction reciprocity are imposed on the
fiber-matrix interface. Application of DQEM to the problem leads to an
overdetermined system of linear equations mainly due to the particular periodic
boundary conditions of the RVE. A least-squares differential quadrature
element method is used to obtain solutions for the governing partial differential
equations of the problem. The numerical results are in excellent agreement with
the available analytical and finite element studies. Moreover, the results
of this study reveal that the presented model can provide highly accurate
results with a very small number of elements and grid points within each
element. In addition, the model shows advantages over conventional analytical
models for fewer simplifying assumptions related to the geometry of the
RVE.