Analysis on Tensioning Schemes for a Super-Long Prestressed Frame Structure

Numerical simulation analysis was conducted for a tensioning schemes of super-long prestressed frame structure, simultaneously, the internal force distribution and deformation law of the structure in integral pouring with synchronous tensioning and segmental pouring with segmental tensioning were analyzed and compared; four tensioning schemes were proposed and calculated respectively. The analysis results showed that compared with the overall tensioning scheme, the scheme of batched pouring and segmental tensioning could improve the internal force distribution of side columns, the maximum bending moment of side columns was significantly reduced, and the tensile stress distribution of concrete at the column ends was also improved. Additionally, it was beneficial to the overall performance of the structure by closing the post-cast strips and tensioning the prestressed reinforcement of the span where the post-cast strips were located for many times, and the beneficial effect was more obvious with the increase of batches. In the actual projects, the scheme of batched tensioning for the reserved post cast-strips should be adopted if conditions permitted.