Research on One-Time Pouring Construction Technology of Side-Span Cast-In-Situ Section and Closed Section

Abstract

In recent years, in the construction process of closed-bridge side spans, construction has often been carried out in accordance with the construction sequence of, first, pouring the cast-in-place section, then preburying strong bone and pouring the closed section, and finally tensioning the closure steel bundle. However, the temperature change during the construction process of the conventional hinges leads to a large deformation of the hinges’ strong bone, which disturbs the concrete of the hinged section, and, at the same time, its high stiffness means that the concrete of the hinged section will not be sufficiently precompressed, thus resulting in the loss of prestressing force. Therefore, it is necessary to study the one-time casting construction technology of the side-span’s cast-in-place and closed sections. In this study, on the basis of introducing the conventional side-span joint-construction technology, the one-time pouring joint-construction technology was adjusted. In order to eliminate the sunlight temperature factor, which has a great influence on the process of joining, finite element analysis was used to further compare and analyze the changes in the internal force and the linearity of the structure under different joining methods. The results of this study show that, by adjusting the counterweight, the adverse effect of the disturbance of the main girder on the concrete at the joint end under the effect of sunshine temperature can be effectively controlled. Also, one-time joint construction is more reasonable for the internal force and deflection deformation of the structure compared with the conventional side-span joining method of a continuous rigid bridge, which is more favorable to the structure. The research methods and conclusions of this paper can provide a reference for the improvement of closed side-span one-time casting construction technology.