Research On Strut-cable Tension Of The Tied Arch Bridge Based On Method Of Vibration Identification And Experimental

Tension calculation is based on the theory of axial force beam about suspenders of the majority of the arch bridge and suspension bridge,and considering the influence of bending rigidity and boundary conditions.Vibration frequency measuring cable tension is widely used in the construction monitoring of cable structure and health monitoring,is also the most simple and the most economic method,there is important significance that testing cable tension In the field of the theory,has achieved remarkable results,but most of the fitting formulas are segmented with tension,will appear the iterative process of tension,and there are some defects that definition of short suspender,parameter identification tension identification method of complex boundary condition.The text does some work on the theory and practical application of the vibration method.Based on the related specifications norms of the current domestic suspenders,the parameters of the typical concrete filled steel tube arch bridge in China are investigated.Based on parameters and slenderness ratio,to design some different numerical models of suspenders,study the application range of the analytical formula of the tension of the suspension under the boundary condition of the classical strings and two ends hinged and fitting formula of suspender tension under the boundary condition of two ends clamped,the preliminary definition of the short suspender and the application range of the kinds of formulas are given,has a large engineering significance.Based on beam vibration theory,this paper introduces a new derivation of fitting formula for the tension of the suspender under boundary condition of two ends clamped;the formula avoids the tedious iterative process of tension.Firstly,the accuracy between the fitting formula and numerical solution are verified,the results show that the error between the fitting formula and the numerical solution can be controlled within 0.2%.Then,the fitting formula is compared with that of other scholars’,the results show that the calculation accuracy of the fitting formula is higher than that of other fitting formulas,and there is no need to iterative tension.In the model test research,firstly,the reliability of the two parameter identification method is verified by a model test results.Then,according to the relevant norms of the domestic suspender to design the indoor test of two suspenders,according to the measured frequency and tension to identify the bending rigidity of the test suspender.The recognition bending rigidity of the suspender is between 0.5~1.0 times of the bending rigidity of the total bond.With Huaxi Guizhou bridge as a example,the calculation formula of suspender tension under three kinds of boundary conditions are compared and studied,the research shows that the actual boundary condition of the suspender is more close to two ends clamped,accuracy of the new derivation of fitting formula is the highest and the error of them be controlled within 5%,it further verifies the correctness of the new derivation of fitting formula,it meets the requirements of the suspender tension identification in practical engineering.At the same time,for the suspenders which have larger error,according to the results of the model test to reselect the bending rigidity to calculate tension,the tension with smaller error is obtained.