Sectional Analysis of Engineered Cementitious Composite Beams

A procedure to predict the flexural response of an Engineered Cementitious Composite (ECC) prismatic beam specimen subjected to four-point bending and its implementation into an Excel spreadsheet are described. It utilises the layered sectional analysis approach and nonlinear ECC constitutive models, allowing for the calculation of the moment-curvature relationship for any selected section of the beam specimen at various stages of loading. Further, the curvature-area method is employed to integrate the sectional response and determine the overall beam deflection profile. To this end, predictions by the proposed method are compared against three series of experiments available in the literature, to provide a better understanding of the relation between the tensile properties of ECC and the corresponding flexural response. It is shown that due to flexural cracking, the beam curvature over the shear span varies nonlinearly from the support and is found to influence the prediction of beam deflection. A series of empirical equations are presented to allow for the quick calculation of tensile strain capacity and tensile strength of ECC based upon flexural test data.