Feasibility Study on Innovative Construction Technology of Friction-Welded Rebar Anchor Bolt (FRAB) System

The anchorage system at column bases plays a critical role in transferring forces between the superstructure and foundation in steel structure-reinforced concrete systems, thereby governing overall seismic performance. This study investigates the seismic behavior of reinforced concrete foundation columns using two anchorage systems: traditional foundation bolts (TFB) and friction-welded rebar anchor bolts (FRAB). A total of six full-scale specimens were tested under quasi-static cyclic loading to evaluate strength, deformation capacity, and failure mechanisms. The FRAB system integrates reinforcing bars with threaded rods through friction welding, aiming to enhance bond performance compared to conventional smooth anchor bolts. Test results indicate that specimens with FRAB exhibit improved seismic capacity and more stable hysteretic behavior than those with TFB. The enhanced performance is attributed to the superior bond characteristics of the welded reinforcing bars, which provide more effective force transfer between steel columns and concrete foundations.