Research on Seismic Performance of Precast Segmental Piers with Steel Pipes Connected via Mortise and Tenon Joints
This study investigates the influence of mortise and tenon joints of steel pipes on the seismic performance of the precast segmental piers.A ramp bridge of an interchange in Fujian Province is used as a case.A full-scale precast segmental pier specimen with steel pipes connected via mortise and tenon joints was prepared,and the seismic responses of the specimen was simulated in MIDAS Civil,and the static load bearing capacity of the specimen was verified.Afterwards,a 1:3.75 scale-down cast-in-place reinforced concrete specimen(RC specimen)and a 1:3.75 scale-down precast segmental specimen with steel pipes connected via mortise and tenon joints(PSBP-MTJ specimen)were prepared for quasi-static tests.The seismic performances of the two scale-down specimens were compared from multiple perspectives,including failure mode,hysteresis curve,skeleton curvature and ductility,cumulative hysteresis energy dissipation,stiffness degradation and residual displacement.It is concluded that both the scale-down specimens succumbed to compressive bending failure,the location of the plastic hinge zone in the PSBP-MTJ specimen is higher than expected due to the existence of the pier-bottom grouting sleeve.The hysteresis curves of the two specimens are smooth without pinching,indicating comparable energy dissipation capacity.The horizontal load bearing capacity of the PSBP-MTJ specimen is 19%higher than that of the RC specimen.No shear slip was observed in the interfaces of adjacent segments of the PSBP-MTJ specimen,in which the prestressing tendons slow down the stiffness degradation and distinctly enhance the self-centering of the pier after an earthquake.Furthermore,the residual displacement of the PSBP-MTJ specimen is only 67%of the RC specimen,and the ratio of residual displacement to maximum displacement is noticeably smaller than that of the specimen with unbonded prestressing tendons.
precast segmental piermortise and tenon joint of steel pipegrouting sleeveseismic performancequasi-static testfinite element method