Various mathematical expressions have been proposed to evaluate or check the lapped length in spliced bars subjected to tension in reinforced concrete members. In this work, 284 tests on spliced bars were assessed in an attempt to improve the previous formulas, with the aim of proposing a new model to predict the lapped length, the transverse reinforcement spacing and the bond stress distribution in concrete beams with different compressive strengths. A genetic algorithm was used to optimise the proposed formulation. For both normal- and high-strength concrete, different bond-stress profiles were developed to predict the resistance provided by bonded embedment. The results clearly show that the proposed bond stress profiles lead to a more accurate evaluation of the lapped length in spliced bars than the expression proposed by the American Concrete Institute.

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