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Experiments were carried out to observe the influence of loading type on concrete beam specimens. Beam specimens made of similar concrete mixture with the same geometry were tested under three point static loading and low velocity drop weight impact loading. Load – displacement behavior, absorbed energy dissipation capacity, stiffnesses, failure modes of beam specimens were obtained and discussed. A finite element (FE) model was prepared in ANSYS Explicit STR software and the results of FE analysis were compared with experimental results. The loading type and loading rate have significant influence on the maximum load, stiffness and energy dissipation capacity. Numerical results obtained from ANSYS Explicit STR FE models are consistent with the experimental results.

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In this study, a comparison is made between force and displacement controlled non-linear FE analyses for an RC beam in flexure with partially developed steel bars. An FE model with slightly unsymmetrical reinforcement was analyzed by applying two-point loading using both force and displacement controlled methods. The responses obtained using ANSYS-13 were validated against available experimental data. Combined comparative display of flexural response of the beam using force and displacement controlled analysis, that has least been addressed in the literature, is given here. Study choses large-deformation-nonlinear plastic analysis scheme, discrete modeling approach for material modeling and program-chosen incremental scheme following Newton-Raphson method. The results show that displacement controlled approach is efficient in terms of time saving and less disk space requirement along with the ability to give falling branch of load-deflection response, if element displacement capacity still exists. Moreover, it gives an early estimate of the load carrying capacity of the structural element along with suitable values of convergence and non-linear solution parameters. However, for a beam with unsymmetrical detailing, force controlled analysis method seems to yield more realistic and practical results in terms of mid span deflection and beam cracking behavior compared with assumed symmetric displacement controlled technique. It also gives true fracture prediction at ultimate load level, which is not true for the displacement controlled method as the computer code forces the model to maintain equal displacements at two load points, falsely increasing the capacity of the beam.