Tests and Design on the Bending Capacity of Flexural Acrylic Beams

In order to study the failure mode and the bending capacity of fluxural acrylic beams, a series of tests were conducted on the acrylic and flexural members, so as to obtain the material properties, failure modes and bending capacity. Besides, the DIC technology was used to obtain the full-field strain distribution. Test results indicated that PMMA had asymmetric material properties, and compression strength was higher than tensile strength. The combination of the fracture in tension zone and burst in compression zone was the major failure mode, and the failure would happen when the tensile strain reached the ultimate strain in tension. The strain distribution in the mid-span met the plan-section assumption, and the neutral axis was slightly above the centroid of the cross-section. Elastic model, elastic-plastic model and simplified model were used to calculate the bending capacity and deflection. Analysis showed that the predictions of elastic model were lower than the test results, while the predictions of elastic-plastic model and the simplified model matched the test result well. It was recommended to use the simplified model to predict the bending capacity and deflections of flexural acrylic beams due to convenient in calculation.