| Initially, the rise of the bridge rotation construction is to adapt to the mountainous region,most bridge type is arch bridge. At present, rotation construction technology is widely used inbridge which across the line has been in operation. Especially in recent years, along with thebig construction of highway and passenger dedicated line, the rotation constructiontechnology of bridge has a rapid development. Currently, the rotation construction technologyis more sophisticated in our country, the heaviest weight of bridge has amounted to17300t,and mostly used in continuous rigid frame, arch bridge and cable-stayed bridge theseself-balanced structure. However, according to different bridge type, the rotation structuredesign and construction specifications are not perfect, the mechanical properties of rotationconstruction girder research is not deep enough, the stress distribution rule of rotatingspherical hinge research is less, which make the process of rotation construction control lackof pertinence. In view of this, this paper based on bridge across Fujia railway and Longhairailway constructed at dedicated line from Zhengzhou to Xuzhou engineering background.For continuous beams with different construction technology before closed, respectively studythe rotation construction of these bridges. The research contents and corresponding results inthe following:1. On the basis of the literature, summarizing the rotation construction bridges at homeand abroad, meanwhile, the rotation construction technology research status is summarized.2. Combined with the specific circumstances of the project designs the rotation structuresystem, and regard the design theory as guidance to get the key technology of construction inorder to achieve good control of rotation structure construction.3. For the differences of main beam first using the cantilever casting or full scaffoldconstruction before closed, to alone design rotation constructed bridge weighing test, andsummarize the calculation process of weighing test. According to the weighing testcalculation results design safe, easy and reliable weighing test program, and obtained thecalculation of the rotation of the parameters and rotating counterweight from the weighingtest results.4. Using MIDAS to establish construction stage model of main beam and analyzing itsmechanics characteristics during construction, the girder vertical level in the process ofcantilever construction is controlled to ensure the high precision closed after rotation. UsingANSYS to build dynamic analysis model, to analyze the girder stress distribution during theprocess of uniform and accelerating rotation. Compared theoretical calculations and finiteelement obtained value of the bridge rotation angular acceleration warning. Calculating thebeam deformation of T-frame under the load of unbalanced moment and balanced weight,obtain the biggest unbalanced weight of the bridge by controlling the eccentric distance of spherical hinge and check the balanced weight by model. Before rotation the spherical hingesupport the structure as a single point, so it is essential to calculate wind resistance stability atmost unfavorable situations to ensure the stability of structure under wind load.5. Analyzing and comparing the normal stress distribution on static contact surface ofspherical hinge by elastic mechanics analytical solutions and standard asymptotic solutions.Theoretical analysis present rational radius and vector height designs of spherical hinge. Thespherical hinge design steps are summarized by the theoretical calculation parameters anddesign the two bridges rotating spherical hinge of the project，which used ANSYS finiteelement model to verify. Spherical hinge finite element model respectively set up contactmodel and whole model, Analyzing and comparing the normal stress distribution on upperrotary table, spherical hinge panels, below rotary table and under static loads. Besides,calculating the normal stress distribution on spherical hinge under the load of unbalancedmoment. |
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