Structural Control of Building Frames Subjected to Earthquake-Induced Excitations Using Shape Memory Alloys

The present article presents a concept for semi-active control of earthquake-induced vibrations in building frames based on smart stressing of the frames using shape memory alloys. Smart cables composed of nickel-titanium shape memory alloy wires are proposed to be installed externally with concrete building frame elements. Upon regulated electrical heating, the nickel-titanium shape memory alloy wires will undergo a martensite to austenite phase transformation resulting in large shrinkage strains. The strain energy thus induced can be used to generate significantly effective control forces in the building frame. The concept is analytically studied by numerical simulations of concrete building frames.