Analysis Of The Twin Towers Four Cable Plane Cable-stayed Bridge For Construction Control

Wth its appearance, mechanical properties, spanning capacity and economy on the superiority,the cable-stayed bridge becomes one of the main bridge of long span Bridges,becoming more and more attention by the bridge engineering, having been rapid development both at home and abroad.The structure of large span cable-stayed bridgeis is more complex, and brings bigger difficulty to the process of construction and the construction control.Therefore, the research of cable-stayed bridge construction control system has important practical value. Cable-stayed bridge construction monitoring mainly includes three aspects of content, namely linear, stress and cable force monitoring, only after full control to make the bridge meet the design requirements. In the process of construction, a scientific and reasonable construction monitoring can ensure the safety and smooth progress for the bridge construction, making into the internal force and linear comply with the design requirements and the requirement of technical specification. A growing number of engineering practice shows that the construction monitoring is one of the important means to avoid the accident of the bridge construction safety. In this paper, the main research content includes the following three parts:First,in this paper, based on a cable-stayed bridge construction monitoring project,the largest span of twin towers four cable plane cable-stayed bridge is 300 m,and the main tower is double diamond couplet of concrete structure.This paper uses the bridge structure finite element program Midas/Civil to discrete bridge structure, determining the best state of girder internal force and stress, cable force of cable-stayed bridge construction process, vertical displacement of main girder.According to target state into the bridge and the selected construction scheme to determine the construction target state, it gets construction control parameters of the theoretical calculation values in each construction stage.Second, the self-tuning control method is used for the bridge construction control with its correction function, filtering function and adjusting function. Measurement methods, measurement principles and measurement devices are introduced in this cable-stayed bridge construction control.The monitoring, including linear, stress and cable force monitoring, realizes the comprehensive control of cable-stayed bridge construction process, ensuring that the bridges meet the design requirements.Third,in the process of monitoring,analysis of monitoring data and calculation results of Midas guarantees that the stress and deformation of cable-stayed bridge during construction are always in a reasonable range,making girder internal force and linear achieve ideal target state,and serving as a reference for the later similar bridge construction monitoring.