Key technology for construction of connection between steel pylon and concrete pile cap of middle pylon of Taizhou Bridge

摘要

Taizhou Bridge is a suspension bridge with three pylons and two 1 080 m main spans. The middle pylon is a steel frame with longitudinal herringbone shape and lateral gate shape. The connection between steel pylon and concrete pile cap is a key part to transfer the huge inner force from the pylon to the foundation. Its construction quality is a critical factor to the overall structural loading of the whole bridge ; therefore the contact ratio between the bearing steel plate of pylon and concrete pile cap is required to be over 75 %. The inclined joint surface in two directions, longitudinally at 39/1 920 and laterally at 1/4, posted a challenge to the construction work. A procedure test was carried out to find an optimal construction method by comparison, and finally the post-injection method was selected as it can meet the requirement of concrete strength and contact ratio at the connection. The successful application of the post-injection method in Taizhou Bridge can nrovide an examnle and reference for similar nroiects in the future.