Seismic performance of a grout-repaired construction defect ina column plastic hinge

Abstract EN

A column built to test the use of high-strength transverse reinforcement in seismically-loaded shear-critical columns was found to have a construction defect.

The column was built to be loaded in double bending, and as such was expected to develop two plastic hinges, one at each end of the column.

In the plastic hinge region at the column top, a void was formed because the concrete could not pass through the load stub’s reinforcing steel cage.

This void was repaired using nonshrink grout placed in a fluid state.

The column was tested after repair, and performed satisfactorily.

The grouted repair was able to support large plastic rotations, and allowed the column to reach a high level of ductility.

The only effects of the repair were slightly reduced concrete dilation and stiffness in the repaired hinge.