A NUMERICAL FRAMEWORK FOR NONLINEAR PERIDYNAMICS ON TWO-DIMENSIONAL MANIFOLDS BASED ON IMPLICIT P-(EC)\bfitk SCHEMES\ast

In this manuscript, an original numerical procedure for the nonlinear peridynamics on arbitrarily shaped two-dimensional (2D) closed manifolds is proposed. When dealing with non -parameterized 2D manifolds at the discrete scale, the problem of computing geodesic distances between two non -adjacent points arise. Here, a routing procedure is implemented for computing geodesic distances by reinterpreting the triangular computational mesh as a non -oriented graph, thus returning a suitable and general method. Moreover, the time integration of the peridynamics equation is demanded to a P-(EC)k formulation of the implicit \beta -Newmark scheme. The convergence of the overall proposed procedure is questioned and rigorously proved. Its abilities and limitations are analyzed by simulating the evolution of a 2D sphere. The performed numerical investigations are mainly motivated by the issues related to the insurgence of singularities in the evolution problem. The obtained results return an interesting picture of the role played by the nonlocal character of the integrodifferential equation in the intricate processes leading to the spontaneous formation of singularities in real materials.