Research On The Construction Control Technology Of Cast-in-situ Shaped Single Tower Cable-stayed Bridge With Full Scaffold

Shaped single tower cable-stayed bridge is a kind of complex space statically indeterminate system consist by three components of the beam, special shaped bridge tower and stay-cables. The program is complex and affected by many factors in the construction process of cable-stayed bridge. In this paper, we study the engineering background of bridge adopts t cast-in-situ construction method, and main tower of the bridge have a strange shape, the two characteristics in the construction technology of bridges are of great difficulty, at the same time stress and linear are hard to control, therefore construction control of cable is vital in the bridge construction.First of all, this paper in the view of research object studies this kind of bridge construction control technique, and introduces construction control methods,contents and matters of this kind of bridge in detail, on the basis of the general control of the configuration, at the same time for stay-cables and special-shaped bridge tower, also make temperature correction of the monitoring result, make research object more comprehensive and accurate, and the control of construction is more secure.Secondly, based on the comprehensive contrast rigid support continuous beam method and energy method, constrained energy method is adopted to establish the completed bridge optimization theory in the construction control process of suspension cable force. In the process of tensioned cable, because it is full framing cast-in-situ construction, and the cable tension caused the reaction force redistribution of scaffold, which may lead to support bearing capacity insufficient, so this paper puts forward adopting two-time cable tensioning method. When the cable tension calculation, adopting forward-iteration method, as needed many complicated calculation in the process of calculating structure influence matrix, this paper puts forward to a trestle-off factor method, through the stents influence matrix and no stents influence matrix to modify the matrix of system matrix, therefore it concluded the structure influence matrix, saves time and manpower, and the method is applied in the engineering background of this paper, obtained the satisfactory results.Thirdly, in the practical construction control of cable-stayed bridge cable force in the process of measuring method and data processing is introduced in detail, at the same time introduces frequency subtraction method and the new fundamental frequency method of the frequency method of data processing, on the basis of the two methods of data processing, it modify new fundamental frequency method to corrected the fundamental frequency, make the modified fundamental frequency closer to reality, and the error is smaller, and the cable force calculated more accurately. Finally, based on the research object, design parameters in the model are analyzed theoretically in the paper, and it respectively analyzes the bridge structure dead weight (construction temporary load), bridge integral stiffness, creep and shrinkage of concrete, temperature on the special-shaped single tower cable-stayed bridge to the state of the bridge. In the process of construction modifying the deviation caused by main design parameters, and ignore the minor design parameters, therefore it is more accurate for cable-stayed bridge construction control.