Study On Timely Adjustment Technology Of Installation Linear Error About Arch Rib Of Large Span Arch Bridge

Long-span arch bridge have developed rapidly in China in recent years, The installation of main arch in Long-span arch bridge is mainly cable-stayed suspension method, the into-arch alignment is closely related with the status and normal operation of arch bridge. Due to the influence of temperature error, decision parameter error, measurement error, calculating error and erecting error and so on ,the actual arch rib alignment is different with the theory. A large number of practice shows that temperature error has obvious effects on the arch rib installation alignment.This paper study the technology of the alignment error for arch installation timely adjustment, the main contents are as follows:①Classify the error for the reason of the formation of alignment error during arch rib installation.②The influence of seasonal temperature difference on the arch rib installation alignment during the hoisting arch rib for the characteristic that temperature error has obvious effect on the arch rib installation alignment is studied, and the change rule of arch rib installation alignment with the seasonal temperature difference is obtained.③Bring in temperature forecasting model of Byes ,carrying out the forecasting of long-time temperature, though forecasting the temperature for somewhere over the year, proving the feasible and rationality for temperature forecasting model of Byes.④The allow range of error for arch rib installation is derived, and the method of alignment error for arch installation timely adjustment is proposed. For different boundary condition at arch foot, study the adjustment method for linear error, including influence matrix method, optimization calculation method and incremental launching method.⑤Take one bridge as an example, using zero-order optimistic method of ANSYS, adopt temperature forecasting model Byes to forecast the installment temperature for arch rib segment. Calculate the cable force and pre-camber of considering the influence of temperature and without considering the influence of temperature. Result shows that cable force change little, but pre-camber change large, after considering the influence of temperature for large span bridge. Considering the influence of temperature, arching linear tallies with objecting linear well for arch rib, Illustrate that this method can solve the problem of liner and internal force effect from temperature error in arch rib installing, and have a highly application value for engineering.