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4





           Deformability of Discrete

           Elements








           4.1 DEFORMATION


           Discrete elements were originally introduced to model problems and processes that
           continuum-based models cannot model correctly. A large class of such problems and
           processes are generally termed ‘problems of discontinua’. However, a large class
           of problems of discontinua involves individual bodies (discrete elements) that can
           deform, fail, fracture and even fragment. Such discrete elements are termed ‘deformable
           discrete elements’.
             Each discrete element represents a single deformable body, which at any instance of
           time occupies a region of space (Figure 4.1). Special meaning is given to some of these
           regions. For instance, one such region B is termed the initial or reference configura-
           tion, while
                                              p ∈ B                              (4.1)




                                                                  x = f(p)

                                                u(p)



                                 z
                                       p




                                         y
                           x

                              Figure 4.1 Deformation of a discrete element.


           The Combined Finite-Discrete Element Method  A. Munjiza
            2004 John Wiley & Sons, Ltd ISBN: 0-470-84199-0
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