Stability Analysis of Open Thin-Wall Box Arch Bridge in Process of Second Phase Concrete Casting

For the arch ring used with concrete open thin-wall construction technology, the second phase concrete casting is needed after the two halves of the arch ring join together in the swivel erection in order to increase the thickness of the walls and bottom slabs. The newly-cast concrete that has not reached the design strength will cause the open thin-wall arch ring to withstand very great load, and the global and local stability of the arch ring structure thus becomes a critical problem that will bring about adverse influences on construction safety. In this paper, by way of example of the Pingdiba Bridge, the finite element software is used to establish a spatial half arch finite element model to simulate the process of the second phase concrete casting. The results of the simulation and analysis show that the local safety stability of the structure at this phase deserves careful attention.