Repair of post-tensioned precast beam to column connections

Earthquakes can cause immense damage to precast structures, rendering them inhabitable. After the 1999 Marmara earthquake in Turkey, research by the Turkish Precast Union stated that 24.50% of the precast structures were damaged with some of this damage being observed in the beam-to-column connections of the structures. Since it is essential to provide those rendered homeless by the earthquake with safe habitable accommodation, repairing medium and slight levels of damage at the connection parts should be undertaken. In order to prove that a repaired connection was sufficiently strong, a precast beam-to-column post-tensioned connection was tested in three phases. In phase one, middle level damage was observed at 6% drift at these connections. In phase two, 1.2, 2.4 and 4.8% drifts were applied three times to the test specimens. As a result of the extra loads applied, little damage was observed. In the last phase, the four connections tested in the first phase were repaired using epoxy resin and then retested. The results from the tests on the repaired precast and the reference undamaged specimens showed that the repaired specimens were sufficiently strong, thus proving that repair to damaged precast beam-to-column post-tensioned connections can be undertaken. Copyright (c) 2010 John Wiley & Sons, Ltd.