Bilateral loading experiment on and analysis of concrete piers using mortar-jointed ultra-high-strength fibre-reinforced concrete precast formwork

The seismic performance of a reinforced concrete pier structure depends greatly on the plastic hinge region at the base of the pier. To improve the plastic hinge region of the structure, we propose using ultra-high-strength fibre-reinforced concrete (UFC) formwork for the concrete cover at the base of the pier. This study describes the structural characteristics of a pier with a base cast using mortar-jointed UFC formwork.
To investigate the structural characteristics, a bilateral circular cyclic loading experiment and a simulation analysis using a fibre model were conducted. The results show that the flexural strength remained stable under a large rotation angle. Even at the rotation angle at the ultimate limit state, crushing failure of the mortar did not occur and the ultimate limit state did not result from mortar damage, because the tensile strength of mortar-filled joints is close to zero, and thus excellent flexural crack distribution performance can be achieved.