216 / 2022-06-07 23:45:16

Lateral cyclic loading tests of precast recycled fine aggregate concrete shear wall with pressed sleeve connections

Precast concrete structure,Shear wall,Recycled aggregate concrete,Pressed sleeve,Seismic performance

Resource and carbon dioxide emission constraints have prompted the implementation of precast structures and recycled aggregate concrete (RAC) in buildings to achieve high-efficiency construction and environmental benefit. An innovative type of precast recycled fine aggregate (RFA) concrete shear walls with pressed sleeve connections was proposed. The detail of the pressed sleeve connection is displayed in Fig. 1, in which the reinforcements are connected by the pressed sleeves. Hydraulic moulds were applied to produce plastic deformation in the sleeve, forming a tight contact between the bar splice and the sleeve. The assembly process of the specimens is indicated in Fig. 2. The wall panel with a loading girder and the foundation were prefabricated in the factory. Then they were assembled through pressed sleeves and lap-splice connections. Finally, the boundary members and the connection region were cast with RAC.



To study the seismic behaviour of the proposed shear walls, seven precast shear wall specimens with the pressed sleeve connections, as well as one reference cast-in-situ specimen, were fabricated and tested under lateral cyclic loading. The effects of the aspect ratio, the axial compression ratio, and the replacement ratio of RFA in concrete of the member were considered in the experiments. Tensile tests on the pressed sleeve connections and the reinforcements confirmed that the sleeve connections had similar strengths with better deformation capacity when compared to the reinforcements (See Fig. 3). The wall specimens were subjected to constant axial load and cyclic horizontal loads, with the test setup displayed in Fig. 4. The typical crack patterns of the precast and cast-in-situ specimens are displayed in Figs. 5 and 6, respectively. The lateral force‒drift angle hysteresis curves of the precast and cast-in-situ specimens are shown in Figs. 7 and 8, with their skeleton curves shown in Fig. 9.



The test results demonstrated that the pressed sleeve connections were capable of transmitting both tensile and compressive force between reinforcements, and the precast shear walls with pressed sleeve connections had almost the same hysteresis behaviour, strengths, ductility coefficient and energy dissipation capacity as the cast-in-situ ones. Moreover, the seismic behaviour of the precast specimens with the RFA replacement ratio of 30% was almost identical to that of the precast specimens with natural aggregate concrete. The drift angles at the yield loads of the precast specimens ranged from 1/463 to 1/267, with their ultimate loads in the range between 1/195 and 1/81. The equivalent viscous damping factor varied from 0.05 to 0.15 prior to severe damage of the specimens. This indicated a favourable deformation and energy consumption capacity of the proposed precast shear walls.