What Are Non-Ductile Buildings?
What are non-ductile buildings? What are the differences between ductility and stiffness? Why are they important factors to consider when it comes to preparing your building for earthquakes?
Ductility describes the flexibility of a building, which impacts how it will perform during an earthquake. This term is commonly used in earthquake engineering to figure out how to design a building that can endure large lateral displacements due to ground shaking (such as earthquakes and tremors). A non-ductile building is highly susceptible to earthquake damage.
Stiffness, on the other hand, refers to how much force is required to shift a building. For example, if you have two buildings, and it takes more force to shift one building over the other, the more steadfast building is stiffer. However, it’s possible to have too much of a good thing when it comes to stiffness. If your building is too stiff, even the smallest of earthquakes can deform it.
The possibility of earthquake damage makes it important to call a seismic retrofitter in to assess your building and figure out the proper balance of ductility and stiffness.
Before 1996, building codes had less strict guidelines for earthquake safety. Because of this, most — if not all — buildings built prior to 1977 are not seismically upgraded. Of these buildings, those that are non-ductile are at the highest risk of earthquake damage. Non-ductile concrete buildings are the most common and dangerous of these, because the columns used to hold them up are either too rigid or structurally unsound during heavy shaking.
These non-ductile buildings include parking garages and office buildings, but also schools, retail stores, and commercial buildings. California is home to many of these non-ductile buildings, which are unsafe and could collapse during an earthquake. In order to remedy this risk, the state has not only updated its building codes, but some cities have passed laws requiring older non-ductile buildings to be retrofitted for safety. In the retrofitting process, seismic contractors reduce your building’s risk of collapse by adding strength to the exterior of columns, adding shear, or even placing steel frames to help your building withstand earthquake force.
If you have non-ductile buildings and you need them retrofitted for safety, contact Saunders Seismic by visiting the website.