Experimental investigation of behaviour and ultimate failure mechanisms of reinforced concrete (RC) beams help to better understand their in-situ reactions in RC structures and enable more realistic designs to be made. In this study, a total of nine RC beams with varying dimensions have been produced and subjected to flexural loading. The mid-section displacements and the loads have been measured. In order to investigate and model the load-displacement behaviour of RC beams of different configurations in detail, a multidimensional data analysis technique has been used. The triangular-base multi dimensional data analysis (TBI) procedure applied herein is generally used for digital terrain modelling especially in geodesy, and photogrammetric engineering and computer-aided modelling applications. Comparison of the experimentally determined relationships with those given by the developed TBI model has revealed close agreements. With the help of this TBI model, the approximate behaviour of an RC beam of certain dimensions for which the strength of concrete and the, amount of reinforcement are given can be determined very closely. The classical finite element method has been used in the prediction of behaviours of RC beams in conjunction with the developed TBI model.