Fictitious Forces Method and Its Application to the Nonlinear Analysis of Plane RC Skeletal Structures

摘要

The fictitious force method (FFM) is an iterative nonlinear elastic analysis method of skeletal structures. The FFM extends the geometrically nonlinear P- method to the materially nonlinear analysis by replacing the original problem with an auxiliary linear problem that includes additional loads that account for the materially nonlinear behavior. The FFM is easily implemented in current linear finite-element analysis (FEA) programs. The FFM is mathematically equivalent to the modified Newton-Raphson method, which means that it converges linearly. The paper (1)applies a combination of FFM with a layers model (FFM-LM) to the quasistatic nonlinear analysis of reinforced concrete plane frames displaying bending-stretching coupling, (2)shows how to implement FFM-LM in a standard FEA program, and (3)applies the latter implementation to illustrative examples.