| For cable-stayed bridges,cable-stayed cables play a very important role both during the construction process and in the completed state.In the construction stage,on the one hand,the cable bears the weight of the beam body and the construction load,on the other hand,the line shape of the beam body can be adjusted by adjusting the cable force,which plays a very important role in the smooth closing of the main span On the one hand,the cable stays under the weight of the beam body and transfers it to the tower pier foundation.On the other hand,the internal force and line shape are further adjusted to adjust the cable force to the optimal cable force to reach or approach the design cable force.Therefore,the cable force control of the cable-stayed bridge is one of the key factors related to the construction control of the cable-stayed bridge.In the actual construction process,due to measurement errors,temperature changes,and limitations of the cable tensioning technology,the actual cable force cannot accurately reach the predetermined ideal value,but the cable force floats up and down around the ideal value.This feature is subject to Just too distributed.This paper takes the influence of cable force error and the shape of the bridge as the main research object,takes an actual composite beam cable-stayed bridge as the engineering background,and uses finite element software to analyze and study.Mainly study the following aspects:(1)The development profiles and characteristics of cable-stayed bridges and composite beam cable-stayed bridges are studied,as well as the necessity of construction control of cable-stayed bridges and the content and methods of cable-stayed control.(2)By studying the working principle of the commonly used cable-stay cable force detection method,the applicability of different cable-force test methods in construction monitoring is compared and analyzed,and the frequency method is proposed to be the most widely used detection method at present.The principle of frequency method and the relationship between frequency and cable force analyze the influence of HDPE casing and temperature on cable measurement.(3)Based on the overview of the project,this article introduces the structural structure of the composite beam cable-stayed bridge,the construction process of the cantilever assembly of the composite beam cable-stayed bridge,the construction steps of the standard beam section of the main beam,and the construction technology of the steel strand cable Process.(4)Study the characteristics of the bridge line under the condition of the overall cable force error,and the characteristics of the bridge line under the cable force error of normal distribution.(5)Obtain the cable force after tension in the construction process of each cable through engineering examples,analyze the characteristics and causes of cable force errors,and analyze the characteristics and causes of the actual bridge alignment. |
