Seismic performance and numerical analysis of steel plate-fiber reinforced concrete composite coupling beams

To improve the seismic performance of reinforced concrete coupling beams with small span-to-height ratio, a steel plate-fiber reinforced concrete coupling beam is proposed in this paper. Quasi-static tests of a steel plate fiber reinforced concrete composite coupling beam and a steel plate-reinforced concrete composite coupling beam have been completed. Seismic performance metrics such as failure process and bearing capacity were analyzed. Finite element software was used to analyze the stress development of concrete, steel plates, and steel rods coupled to beams under three operating conditions, as well as the distribution laws of axial forces, shear forces, and bending moments of the embedded plates. The results show that steel plate fiber reinforced concrete coupling beam has high bearing capacity, energy dissipation capacity and ductility. The addition of fibers effectively controls the expansion of the initial cracks in the concrete and works better with steel plates. The maximum stress of the embedded steel plate is at the junction of the beam walls. The axial force of the coupling beam steel plate is U-shaped, which is subjected to a large axial force at the end and the minimum axial force in the middle, but the shear force at the end of the coupling beam steel plate is the smallest, and the closer to the middle, the greater the shear force.