Seismic response and impairment of RC-ECC bridge pier with socket connection
To mitigate seismic damage to bridge substructures in high-intensity regions while enhancing bridge construction efficiency,high-ductility cementitious composite material,known as Engineered Cementitious Composites(ECC),was proposed to be used in the potential plastic zones of bridge piers.Additionally,a prefabricated socket connection technology was employed for the connections between piers and foundations.Consequently,an experimental design was implemented,including a socket-connected prefabricated RC-ECC pier,a monolithic cast-in-place RC-ECC pier,and a monolithic cast-in-place RC pier.Through shaking table tests,the dynamic response characteristics and structural failure modes under various types and intensities of ground motion were investigated.A shortcoming of existing research focused on quasi-static tests was addressed.The seismic damage development in the piers was quantified and discussed using various damage indices.Results indicate ECC works synergistically with the longitudinal reinforcement of the piers,providing a similar confinement effect as stirrups,thereby reducing the strain amplitude of the longitudinal reinforcement in the plastic regions of RC-ECC piers.Despite having only half the amount of stirrups compared to the RC pier,RC-ECC piers still demonstrated superior seismic performance under near-field pulse earthquake.The latter have considerably lighter damage and facilitate post-earthquake restoration.The existing damage evaluation methods tend to underestimate the ductility capacity of RC-ECC piers,resulting in theoretically exaggerated damage calculations.Additionally,the socket connection with ECC socket segment performs well.Only minor surface grout peeling is observed under high-intensity conditions.Research results demonstrate the feasibility of using ECC and socket connections to reduce structural damage and improve construction efficiency.The seismic performance and damage of the socket-connected RC-ECC pier are essentially equivalent to those of the cast-in-place RC-ECC pier,and both have significant advantages over the cast-in-place RC pier.It is recommended to use a method based on the principle of energy dissipation through bending for damage assessment at the current stage.
万方数据
维普
