Severl Key Issues Study In Construction Control To Long-span Suspension Bridge

Lishui River Bridge is a large bridge in Zhangjiajie to Huayuan highway。Bridge is located at the junction of Yongshun County of western HunanAutonomous Prefecture and Yongding District of Zhangjiajie,across the Lishui RiverGorge, which is a typical mountain suspension bridge, Single span simply supportedsteel truss suspension bridge composed of the main bridge。According to the actualconstruction situation of the of Lishui River Bridge, this paper have didConstruction monitoring research. The following are the major work:(1)The existing gravity loads flat flexible cable analysis methods weresummarized, the total can be divided into two categories, one category is theequilibrium geometry method, anther is the energy variational method.And Make Adetailed comparison to three kinds of theory of the balance balance which includeelastic catenary theory, elastic catenary theory and parabola theories), draw theirrespective advantages and shortcomings. Elastic catenary theory is of the highestprecision, but computational complexity Parabolic theory and accurate catenarytheories are relatively poor precision, but calculate.(2)Use analytic method software CABLE_CCCAL got Non stress length andEmpty cable state cable saddle pre bias of the main cable. Guiding the constructionperiod of the saddle installation(3)Use analytic method software CABLE_CCCAL got theory elevation ofthe vicinity point of each span of Lishui River Bridge Strand。Use a parabolic theoryinfluence obtain the influence of The temperature change, span changes and preraisedheight of Tower on the datum strand midspan elevation, which guide the riverbridge 's main cable erection.(4)The ideal tension of anchor span in the Cable status is obtained bycalculating. which Guide the river bridge during the construction of anchor spantension construction, and prevent the cable saddle wire strands of sliding andsaddles effectively(5)Use the analytic method of software CABLE_CCCAL got The main spancable clamp lofting coordinate and vertical sling blanking length without stress in the condition of the main cable, saddle, and its twelve dead load comply with thedesign. For the late bridge to comply with the design requirements of linear laid afoundation(6)Based on the parabolic cable adjustment formula to calculate the cableadjusting value is bound to bring this background error adjustment of cable,In thispaper the elastic catenary theory for the adjustment of datum strand.Based on thedatum strand in the empty cable state is catenary of this characteristic, the stateequation is derived and solved by Newton Raphson Diedefa. Preparation of twomodels:" by the mid-span sag and non stress length" and" by the unstressed length ofmidspan sag of"...