Strength and deformation of confined and unconfined grouted concrete masonry

Although concrete masonry is a composite material, its gross properties are used in structural design. It is well known that under uniaxial compression, grouted concrete masonry fails under stress levels lower than that of the hollow masonry blockwork. To improve the compressive strength of masonry, the authors examined the effectiveness of inserting rolled fine wire mesh or welded wire mesh into the voids of the hollow concrete masonry prior to grouting. This inexpensive method of confining the grout increased the compressive strength of the masonry up to 38%. Simple and refined equations have been fitted to the stress-strain data of the masonry with the refined form of the equation being found more appropriate. The stress-strain curves appear to predict the peak and postpeak characteristics of the unconfined and confined prisms accurately. The appropriateness of the refined equation is demonstrated by predicting the moment curvature relations of short masonry piers tested under axial and lateral loading.