Study Of Closure Technics For Long Span PC Bridges Of Rigid Frame Combined Continuous Beam

Long span PC Bridges of rigid frame combined continuous beam, which are developed quickly during recent yeas. New demands are put forward for research in design and construction of this type along with more bridges of this type been building and taking into effect.Closure stage is the key stage of construction, in which the permanent primordial status of the bridge achieved. Due to its long multi-span character, long span rigid frame combined continuous beam bridges have more closure segments, longer girders, more duplicated technics, longer term of erection, and more diversity of structure architecture and load case. They are affected by many facts of environment. Studies about closure technics of PC rigid frame combined continuous beam bridges should have some practical and theoretical value.In order to solve problems of the background bridge- Xinjiang YiliBridge during closure construction, this paper discussed the closure technics of PC rigid frame combined continuous beam bridge at aspects of design, construction, monitoring. As an extension, general pattern of the same type bridges was studied:A. At the aspect of design, this paper discussed affecting of the structure's status by the difference of joining sequence. By means of FEA, here got the general pattern of extremum points on displacement and stress curve, backed the altering of sequence. The results conduced to decision of the project and bridges of the same type.B. At the aspect of construction, technics of closure segment casting for PC rigid frame combined continuous beam bridge are introduced in detail in this paper. As for Yili Bridge, advice were put forward such as outside framework and locking for safety of the bridge, pushing for capability of load bearing, unilateral suspender and weight balance for cutting the constructing time, batching of tension-wire, etc, which covered the constructing of the project.C. At the aspect of monitoring, this paper also went deep into discussion of technics of constructing monitoring during closure stage, such as contents, methodof putting into practice. As an application, Yili Bridge was successfully monitored, which backed the judging of the bridge's real state and reaction of the site load, decision of constructing command.Yili Bridge has successfully joined;its characteristic was qualified to design criterion. Thus the way of studies about PC rigid frame combined continuous beam bridges feasible. It has some referential value to bridges of the same type.