A partition-of-unity based 'FE-Meshfree' hexahedral element with continuous nodal stress

A hybrid 'FE-Meshfree' eight-node hexahedral element with continuous nodal stress (Hexa8-CNS) is developed using the concept of partition of unity (PU). One feature of Hexa8-CNS is to achieve continuous nodal stress, meanwhile construct high-order global approximations without adding external node, which leads to high accuracy and convergence rate. Moreover, it is free from the linear dependence problem which cripples many of the PU-based finite elements. Numerical results show that the performance of the element is superior to that of Hexa8 element. Besides, the present element has excellent mesh distortion tolerant capabilities.