The Research Of Closure Jacking-force Of Continuous Rigid Frame Bridge

The shrinkage and creep of Long-span Continuous Rigid Frame Bridge with high pierwill make the beam body vertical deflection and horizontal displacement and the additionalinternal force, deflection caused by the influence of main pier, bridge appearance anddriving comfort, while the main pier stress adversely affect.Therefore in the pier beam consolidation, in closure section steel and closing bracketand the lock template before the closure section beam is applied between the top of piers forhorizontal thrust and make it a partial, the longitudinal horizontal displacement of pier topafter offset will occur.So the research has important significance of applied creep size change and Bridgecontraction jacking force closure of continuous rigid frame bridge with high pier underdifferent conditions.Taking Shenfu super highway northern part of the Shaanxi Province Qi Leng theYellow River bridge as the basis, using the finite element software MIDAS/Civil toestablish continuous rigid frame bridge model, and by changing its size and the jackingforce of contraction of the time of creep, read the longitudinal displacement of the size ofthe pier top model, summarize the regularity of longitudinal displacement of the top of thepier.The Push front、Push back、before constant load, constant load applied before applyingfor30days and constant load applied for10years in five cases, the premise of jacking forceconstant change of height span bridge, longitudinal displacement of the pier height andsummarize the rules.During the construction of continuous rigid frame bridge, the applied closure jackingforce on the top of the pier is essential, and should be chosen reasonably according to thecharacteristics of the bridge itself, thus the bridge will be more safety, more durability.