Which Building Types Are Most at Risk During an Earthquake?
There are several types of buildings, including soft-story, tilt-up, steel moment frame, non-ductile concrete, and URM (unreinforced masonry). What are their characteristics, and what can be determined as vulnerable when facing an earthquake?
Soft-story structures are common among apartment buildings, characterized by open parking on the ground floor and dwelling units built above. In other types of buildings (retail, commercial), the soft-story ground floor may be enclosed by windows that do not provide any structural support, and as a result, the structures are considered extremely vulnerable to collapse in a major earthquake.
Tilt-up buildings are created by pouring a building’s walls directly at the job site and then levitating or “tilting” the panels into position. Many new commercial buildings in California and across the nation utilize this method.
Many tilt-up structures built before 1994 were constructed with limited or weak connections that have been proven to fail in an earthquake, causing severe damage and/or collapse. Seismic retrofitting can easily correct these building defects.
Steel moment frame structures are characterized by using a rigid steel frame of beams connected to columns to support the many floors of the structure. These structures can sustain brittle fracturing of the steel frames at the welded joints between the beams and the columns. If the moment frames reveal cracks and fissures, they may be susceptible to collapse in a major earthquake.
Non-ductile concrete buildings have concrete floors and/or roofs supported by concrete walls, columns, and/or frames. Due to their rigid construction and limited capacity to absorb the energy of strong ground shaking, these structures are at risk of collapse in an earthquake.
URM (unreinforced masonry) buildings are categorized by walls (both load-bearing and not) and other structures made of brick, cinderblock, or other masonry materials that are not braced with rebar or another reinforcing material. Due to the lack of strength in the masonry, these buildings are susceptible to earthquake damage when the structural masonry comes apart.
Strengthen Your Building Against Earthquakes with Saunders Seismic
Understanding your building’s vulnerabilities is the first step to safeguarding your property and occupants during an earthquake. Saunders Seismic specializes in seismic retrofits for all types of structures, including soft-story, tilt-up, and unreinforced masonry buildings.
Contact us today to schedule a consultation and learn how we can help protect your assets and ensure your building meets modern safety standards.