The BRACED project investigated the ultimate behaviour of concentrically braced frames(CBFs). The research programme was designed to validate empirical models for theductility capacity of hollow section bracing members and recent proposals for theimproved detailing of gusset plate connections, to identify active yield mechanisms andfailure modes in different brace member/connection configurations, and to provideessential data on the earthquake response of European CBFs. The central element of theintegrated experimental and numerical research programme is a series of shake tableexperiments on full-scale model single-storey CBFs designed to Eurocode 8 (CEN, 2004).Twelve separate experiments were performed on the Azalee seismic testing facility at CEASaclay. The properties of the brace members and gusset plate connections were variedbetween experiments to examine a range of feasible properties and to investigate theinfluence of conventional and improved design details on frame response. Each experimentexamined the response of the test frame and brace-gusset plate specimens to tableexcitations scaled to produce elastic response, brace buckling/yielding and brace fracture.These experiments were supported by complementary quasi-static cyclic tests andcorrelative numerical simulations using pushover and time-history analysis using theOpenSees seismic analysis software. The outputs of the research programme represent aunique set of data on the ultimate earthquake response of CBFs with realistic bracemembers and connections. The principal experimental outcomes include measurements ofelastic frame stiffness and its evolution with brace damage, measurements of thedisplacement ductility capacity of the brace specimens; an evaluation of the influence ofbrace connection configuration and gusset plate detailing on frame stiffness, damping andductility; and observations on the contributions of brace and connection yielding to overallinelastic deformation of CBFs.