Earthquakes have shown that seismically deficient RC frames are particularly vulnerable to seismic action. Direct observation of damaged structures has shown that damage occurs usually at the beam-column joints with failure in bending or shear, depending on geometry and reinforcement distribution and type. After earthquake structures were classified as slightly damaged, thus being uneconomic to replace them, at least in the short term. For this reason suitable means of repairs of the beam column joint area are being studied. This book highlights the cyclic tests carried out on beam-column...