A FIBER BEAM ELEMENT FOR THE FINITE PARTICLE METHOD CONSIDERING SHEAR AND TORSION DEFORMATON

To improve the accuracy of the finite particle method (FPM) for solving structural elastoplastic problems, the fiber beam model is combined with the solution framework of FPM. The formulas for solving the particle internal forces of the FPM fiber beam element considering shear and torsion deformation are deduced. The element uses the Timoshenko beam theory to describe the deformation state of the beam section. The displacements of an arbitrary point on the section are determined by the element pure deformation components in the element. The three-dimensional constitutive relationships of fiber materials are used in the element to consider the coupling effects between bending, shear and torsion deformation. Several numerical tests are conducted. The results show that the proposed fiber beam element can effectively simulate the elastoplastic behavior of the structure and shows higher accuracy than the plastic hinge method.