Study On Mechanical Behavior Of Continual Rigid Frame Bridge With Short Piers

Continuous rigid frame bridge is more and more favored by designers and owners because of its mature construction method,low construction difficulty,strong spanning ability,high driving comfort,easy maintenance,low cost,beautiful appearance and so on.However,when the bridge across the lake,wetland or municipal bridge design there is a high degree of restrictions,a short pier continuous rigid frame bridge is needed,and continuous rigid frame bridge for a number of statically indeterminate structure,subject to external factors easily lead to larger structure of the internal force,which often limits the use of a dwarf continuous rigid frame bridge.In this paper,the structural analysis of the main piers of the three-span dwarf continuous rigid frame bridge is carried out by analyzing the structural stress of the main piers,the compaction ratio,the mid-span ratio and the deviation sensitivity.Force law,for the dwarf continuous rigid frame bridge to promote the design to provide some reference.(1) In this paper,the ratio of the height of the main pier and the span of the main span of the three-span continuous rigid frame bridge is studied.The scheme of 12 kinds of pier-span ratio is designed.The span of the main span is 60 m,15m,pier across the range of 1/15 ~ 1/4.The variation law of structural stress and deformation under four kinds of conditions,such as dead load,temperature load,moving load and uneven settlement of piers,are used to compare the change of stress with the piers of the exponential function.According to the results,when the ratio of the height of the main pier and the span of the main span is smaller than 1/6,we can definite the bridge as short pier continuous rigid frame bridge.(2) In this paper,the comparative analysis of the cross-section of the piers of the three-span piles is made.3 representative sections of the piers are selected and analyzed respectively.The results are compared with those in the dead load,the temperature load,the moving load and the pier The internal force and deformation law of the piled continuous rigid frame bridge under the four kinds of load conditions,and provide some reference for the design of the main piers.According to the analysis results,Under the condition of stability,the thin wall solid pier is more suitable for short pier continuous rigid frame bridge.(3) In this paper,four kinds of closure deviation schemes are designed,including deviation and none deviation in both normal continuous rigid frame bridge and shortpier continuous rigid frame bridge.for different deviations to take additional counterweight of the program to close,and then analyze the bridge under there oprating conditions,including in the construction plus additional weight,the bridge is built(bridge phase two dead load),operating for three years,The influence of the short pier continuous rigid frame bridge on the deviation of the mid-span closure is analyzed by comparing the internal force and the deformation of the structure.