Earthquake Retrofitting Services for Unreinforced Masonry Buildings (URM)

Unreinforced masonry buildings are especially vulnerable to earthquakes. In fact, the FEMA report “Unreinforced Masonry Buildings and Earthquakes: Developing Successful Risk Reduction Programs,” states, “More than any other kind of construction, [this type of building] can be singled out as being seismically vulnerable.”

It is the responsibility of URM building owners to ensure that damage to their structure, as well as death and injury to tenants, employees and pedestrians is minimized. This can be accomplished by having an earthquake retrofit of your historic or heritage building performed by Optimum Seismic.

The Reality of Unreinforced Masonry.

URM is generally defined as masonry lacking reinforcement within. The masonry is made of earthen materials, such as stone, brick, hollow-concrete brick, clay tile or adobe. Many URM buildings also feature heavy timber columns and beams within the interior. The heavy and typically weak walls of these structures contribute to their instability during earthquakes, and they often lack significant horizontal force resistance. Additionally, many include parapets, chimneys or other heavy ornamentation. Overall, URM buildings are said to provide very little or no ductility – the toughness, deformability or energy absorption capacity – to withstand a significant earthquake.

Optimum Seismic’s team of engineers and construction experts have many years of experience in retrofitting historic and heritage buildings to help prevent collapse and injury in earthquakes.