Enhancing the out-of-plane behaviour of masonry infill walls using engineered cementitious composites

A novel technique for retrofitting masonry infill walls is proposed. The technique looks at the use of a thin layer of an engineered cementitious composite to improve the out-of-plane response of infill masonry walls. To demonstrate the proposed technique, fifteen plain and retrofitted masonry beam-like specimens were tested under four-point loading to failure. The influence of two parameters was examined, namely loading rate and bond interface. The results demonstrate that the use of a thin ECC layer significantly improved the strength and ductility of the test specimens. The specimens with an ECC layer that was partially bonded to the masonry exhibited higher ductility than those in which the ECC
layer was fully bonded, albeit they also demonstrated a slightly lower load-carrying capacity. It was found that the increase in ductility was primarily due to the formation of more uniformly spaced microcracks. The results also demonstrate that as the rate of loading increased, the load-carrying capacity
increased, whereas the ductility decreased. Three-dimensional nonlinear finite element simulations were carried out to study the underlying mechanisms responsible for the observed flexural response.