Plastic hinge development in limited ductile rectangular reinforced concrete walls

This paper provides a brief overview of a recently completed experimental testing program consisting of limited ductile reinforced concrete (RC) walls. The experimental program included one monolithic cast in-situ rectangular wall specimen, one monolithic cast in-situ box shaped building core specimen and two jointed precast box shaped building core specimens. The specimens were tested using the MAST system at Swinburne University of Technology. They were tested under cyclic in-plane unidirectional lateral load with a shear-span ratio of 6.5. The specimens were detailed to best match typical RC construction practices in Australia, which generally results in limited ductile structures to AS 1170.4. This reinforcement detailing consisted of a continuous mat of constant-spaced horizontal and vertical reinforcement with a lap splice at the base of the wall. A preliminary set of results for the cast in-situ rectangular wall specimen have been summarised within the paper. The lap splice at the base of the rectangular wall resulted in it having a somewhat different post yield displacement response than what is typically seen in RC wall tests performed elsewhere in literature. Instead of a typical plastic hinge with distributed cracks being developed, a 'two crack' plastic hinge was formed. This consisted of one major crack at the base of the wall and another at the top of the lap splice, with only hairline cracks developing between these two major cracks. The majority of the plastic rotation was concentrated in each of these two major cracks.