The harmonic coupled finite strip method applied to geometric nonlinear analysis of reinforced concrete folded plate structures

This paper presents the theoretical and numerical analysis of two reinforced concrete folded plate structures (RCFPS) of span length 20 and 30 m, according to linear predictions and predictions of geometric non-linear behavior of the structure (large displacements). Characteristic cross-sections are designed according to Eurocode 2 (EC 2), on the basis of internal forces calculated using the linear finite strip method (FSM). The ultimate resistance of the characteristic cross-sections is presented through diagrams of interaction. It was found that the safety factors of selected cross sections calculated assuming linear structural behavior in almost all the cases are on the safe side in relation to the results obtained assuming large displacements. Significant differences between the results of linear and nonlinear theory are observed only for larger RCFPS. The stability analysis required during the design process is performed using the complex harmonic coupled finite strip method (HCFSM). In the case of the geometric stiffness-matrix computation to solve the large deflection problem, coupling of all series terms in the HCFSM formulation greatly increases the computation time when a large number of series terms are used. In order to cope with dramatic increase of the computation time due to the coupling of all series terms in the HCFSM formulation, a combined application of MPI and OpenMP parallelization methods in the cloud computing environment is used.