Study On Measurement Control Technology Of Prestressed Concrete Bridge Construction And Its Applications

With the progress of technology and the development of bridge construction, there mushroomed a whole variety of skill-advanced bridge projects. Being attributed to the advantages of excellent integrated quality, firm configuration rigidity, little distortion, aseismatic capability and sophisticated design, the skill of prestressed concrete bridge dominates in the field of bridge construction. The demand for measuring method and accuracy, data-processing method, etc. is becoming higher with the rapid construction of huge bridge projects.In accordance with the field experiment of Sutong Bridge base construction, this article studies and analyzes the data processing problem of bridge construction control network, the construction measurement skill of the bridge foundation and the measurement control technology of short line precasted and fabricasted for the roof beams. The main research findings are as follows:1. The necessary accuracy of the primary construction network point position is deduced from the highest measuring accuracy of the critical part construction. The choice of project zone, perspective plane and central meridian is analyzed in the process of construction control network adjustment.2. The method and the accuracy of height transfer are analyzed. Combining with the precise height transfer of part leaping over Sutong Bridge, the methods of confirm weight are analyzed. The rationalization of height transfer weight is under a concrete analysis by means of "Helmert" variance constitution estimation method, accidental mean square error comparison method respectively.3. The accuracy and the various layout methods of density control points encrypt during construction are discussed. The accuracy comparison of total station instrument method and GPS method is also conducted. With the analysis of the pile driving barge process principles and discuss the equations of the GPS-RTK coordinates conversion technology parameters, the layout accuracy of the GPS-RTK method is analyzed and compared with the measured results of total station instrument.4. According to the surveyed coordinate of steel pipe circle, the adjustment of condition equations and the position of circumferences points is studied, the choice of the pipe circle points' position are analyzed and experimented for the influence to precision. The measurement control and orientation check method to the sink of the steel suspension-box are studied, and analyzed the orientation check precision.5. Expatiated the method of box-beam prefabricated by the way of long-line and short-line. Studied the configuration measurement control method of the box-beam piece which prefabricated by the way of short-line, including local coordinate system's layout in precasting place, the coordinate conversion of control node on box-beam, the measurement control method of the box-beam piece, the join degrees of control piece, etc. The box-beam precasted line shape control procedure is worked out, and applied in example analysis.6. Studied the configuration measurement control method of the box-beam piece which put together cantilever.The box-beam fabricated configuration measurement data procedure is worked out, and applied in example analysis.