Concrete moment frame buildings have historically had poor seismic performance, resulting in stricter code requirements over the years. This type of building can be categorized as high risk, due to the number of people generally present in large office buildings. The primary deficiency of older concrete moment frame buildings is the lack of confinement and joint reinforcing, resulting in a non-ductile (inability to absorb energy) system. Typical damage to concrete moment frame structures is as follows:
- Columns (failure of columns due to inadequate reinforcing and strong beam/weak column conditions often resulting in collapse)
- Joints (failure of joints due to inadequate reinforcing)
- Infill Walls (failure of masonry infill walls between beams and columns)
