Nonlinear analysis method of truss structures with no consideration of geometric stiffness
The change of structural stiffness in the case of large deformation should be specially considered in the nonlin-ear analysis of structures,However,the derivation process of tangential stiffness or geometric stiffness is complicated,so many researches focus on the derivation of structural element stiffness matrix and ignore the whole process of nonlinear a-nalysis.Based on the mechanical mechanism of incremental iterative nonlinear analysis,the nonlinear behavior of the truss structure can be analyzed by using only elastic or elastic-plastic stiffness without considering the geometric stiffness of the truss structure while ensuring the solution accuracy of the element node recovery force.By comparison and analysis with the conventional geometrical stiffness,the calculated results are in agreement,but the calculation time and iteration times are increased slightly.The nonlinear calculation process of truss structure without considering geometrical stiffness has clear physical meaning and can be extended to other types of structures.