We were asked to investigate distress at a reinforced concrete parking structure. The Owner noted cracking at an exterior beam and became concerned. We performed an initial visual condition assessment. It was apparent from the assessment that the location had been previously repaired, and the repair had failed. It was also clear that reinforcing steel was too close to the surface.
We developed a repair plan based on the visual assessment. As is common with this type of repair, several repair options were provided based on the ultimate depth of repair. (It is often not possible to know the ultimate level of distress until the contractor begins to remove the damaged concrete.)
Once a contractor was selected, they began to remove the damaged patch. It became apparent that the beam had an original construction defect that consisted of a cold joint that had failed. (A cold joint is the unintended joint between two concrete placements because of a delay in concrete placement.) The previous repair was doomed to fail because the cause of the distress was never addressed.
Based on observed distress, the repair plan was modified to address the latent defect. The contractor removed additional concrete and provided a long-term solution. This is one of the major reasons to have a consultant involved in the repair process. If the work was done without a consultant, the contractor would have likely done another surface patch, and never actually addressed the real source of the problem. It is also important to have a consultant during construction because even the best repair contractor will do a better job if an independent party is reviewing their work.
