Study On The Grillage Analogy Method In Irregular Box Grider Bridge

In recent years, the city viaduct, overpass with each passing day, in order to adapt to theHighway Interchange lead engineering, usually need to build wider and curvature of the upperstructure, a large number of special-shaped girder bridge was constructed, and as goodintegrity, bending and torsion stiffness box girder is most suitable for the development ofshaped beam bridge. Therefore, specifically for special-shaped box girder of the research isvery meaningful.Based on practical engineering, this paper select a wider variable curvature of special-shaped box girder bridge, with finite element program MIDAS CIVIL as auxiliary, detail theclassical grillage analogy method in the practical application of the special-shaped box girderbridge, and the sectional parameters of special-shaped box girder are discussed in this paper,mainly has the following several aspects.1."Bridge Deck Behaviour", a book as a reference, and systematically expounded beamgrid in the upper structure of the application, including the stiffness equivalence principle andauxiliary instance and output processing.2. Beam method through an example to show that relying on computer analysis andinterface eccentric position selection, independent of the choice of the cross-sectional form,to simulate the actual structure lies in the stiffness of the equivalent, ignoring the equivalentof a secondary part of feelings and structure shape for modeling brought many conveniences.3. Plate element model as a reference, by the reaction forces, comparing the results of thedeflection, stress, showed that sorghum grid analysis in the analysis of the reliability andavailability of the shaped box girder bridges.4. Irregular grider bridge four very important parameter analysis is discussed in detail:(1) load transverse distribution factor, generally used for single-beam analysis comparing theresults of the results with the single beam by beam grid, indicating that single beam do thiswider shaped box girder analysis limitations;(2) shear lag, beam elements can not reflect theshear lag effect in box girder bridge Specifications given width reduction to reflect;(3)support arrangement, bearing arrangement directly affect the force distribution andtransmission, three alternatives are discussed in detail shaped beam bridge bearing selected; (4) transverse grillage, stiffness size selection and the selection of the diaphragm, cross-member simulation obtained by increasing or decreasing each parameter on the overall force.