Experimental Study On Seismic Performance Of Precast Concrete Frame Joints

Precast concrete structure has a series of advantages, such as:short construction period, high-quality products, low energy consumption and little environmental pollution, which is a necessary choice for realizing the sustainable development of construction industry. However, an important factor restricting the development of precast concrete structure is the joint connectivity issues. For fabricated frame structure, beam-column joints is most important, it affects the seismic behavior of fabricated frame structure directly.This paper is originated from Beijing Science and Technology Project" Development and application of new efficient products for large-diameter steel sleeve grouting connection", by means of low cyclic loading test on model specimens, the anti-seismic property of fabricated concrete frame joints using large-diameter steel sleeve grouting connections were systematically studied.Firstly, four full-scale framework joints were designed and produced, they are fabricated concrete frame interior joint and corresponding common cast-in-situ interior joint, fabricated concrete frame exterior joint and corresponding common cast-in-situ exterior joint. Tests under low cyclic reversed loading on these joints were carried out, detailed the whole loading process of model specimens, according to the experimental phenomenon, four stages of joints were summarized, which are cracking, yielding, limitation and destruction, then achieved the load, displacement and rotation of beam-end as well as the strain value of concrete and steel, created the hysteretic curves of P-△、 M-(?), and calculated the parameter of energy dissipation, like ductility, work ratio and equivalent viscous damping coefficient. Finally, a comparison was made between precast frame joints and ordinary cast-in-situ frame joints, to analyzed the similarities and differences of seismic indicators such as ductility, energy dissipation and working mechanism.The study indicates that precast frame joints have the similar failure mode with cast-in-situ frame joints, meanwhile, all the four joints were realized the beam-end plastic hinge failure mechanism and had good mechanics and seismic performance.