Research Of Construction Control On Bridge Of P.C. Simply-supported Beam Of Tension-compression Bi-action

This dissertation presents construction control on bridge of P.C. simply-supported girder of tension-compression bi-action. In recent years, the special girder is at an experimental stage in China. The dissertation regards You-Dun-Gang Bridge as study object; verifies materials quality of 30CrMnSi steel tube and balance stabilization of the system of pre-compression tube, analyzes development tendency to up-flexion and lateral deformation of P.C. girder by monitoring at construction site, stress of mainly-controlled section of girder identity and the actual rigidity of bridge accord with the design document by the modern surveying technique, an erecting case by floating crane, named by Double Ship Platform Crane in coordination with the Traction System of Balance between Anchor and Cable, was drawn up and put it to use, it provides a serial of empirical data for floating crane construction. The main results present as follows:1. Verified the applicability of the recommended design indicators that an alloy of 30CrMnSi high-strength steel tube under the heat treatment condition was used by some bridges, further verified the balance stability of the pre-compression tube system.2. Analyzed reasons why give rise to up-flexion of P.C. girder, draws up some curves named by "Instantaneous and creep up-flexion" by observation analysis. It made development of up-flexion and establishment of effective prestressed force confirm mutually. Analyzed the reasons why lead to lateral deformation of P.C. girder and brought forth the corresponding control measures, amended design pretension procedures, and provided the referred construction methods in similar projects.3. Some results from construction monitoring by Steel-Wire strain sensor and simple strain gauge showed that stress of mainly-controlled section of girder accords with the design document, effective prestressed force of girder achieved the design demand. 4. Evaluated indirectly the actual rigidity of bridge by 891-2 picking vibration tool and related secondary instrumentations. The result of evaluation reaches the design demands in that a close correspondence between observed value with the design value.5. As study on floating crane construction, explored a reasonable navigation path by an experimental girder-model, and designed a simple and practical transverse torsion resistance measure for construction safety.Research results to the deepening of P.C. girder of tension-compression bi-action of understanding, improve the level of construction management and prevent from the dangerous construction condition is of great significance.