Experimental study on seismic response of precast bridge piers with double-grouted sleeve connections

摘要

In recent years accelerated bridge construction (ABC) has become increasingly popular all over the world because of its good quality, cost effectiveness and decreasing bridge construction time. Much attention has been paid to substructure connections for ABC systems. Grouting sleeve (GS) is one of the most widely used connection methods. In this study, three 1/4 scale column models with two joints connected by different technique were conducted according to an actual precast bridge project. Two precast columns (B2, C2) were made to study the location effect of GS. One conventional cast-in-place (CIP) column (A2) was conducted as reference specimen. The seismic performance of the columns was investigated and compared. Experimental results showed that cracks for B2 with GS connectors in the column foot were less and plastic hinge had shifted to the ends of GS. The energy dissipation capacity of B2 was lower than that of reference specimen. Specimen C2 with GS connectors in the pier foundation appeared similar seismic performance to reference CIP A2, and the peak load of each cycle was higher due to the high-strength grout reinforced the interface bonding behavior between column and base. The displacement ductility coefficients for A2, B2 and C2 were 6.87, 5.14 and 6.42 respectively, and the GS connecting technique like B2 was not suggested for application in the high seismic area. The column-cap beam joint of all specimens remained intact throughout the testing from the strain results of the longitudinal bar.