Research On Key Problems Of Steel Tubular Truss Structure Of Trestle Bridge In Cement Plant

The steel tubular truss structure is applied more and more extensively in trestlebridge for transportation in cement plant,based on the design of steel truss structurewith different span,several key problems of the structure is analyzed in thispaper,including:overall stability of steel tubular structure, tube-gusset plateconnections and vibration performance of trestle bridge.This paper carry out the overall stability analysis of steel tubular truss structureswith different parameter, and the calculation formula of ultimate bearing capacity isproposed.Then the parametric study is conducted, the results show that the overallstability of the structures is dominated by the span-width ratio, and the formula forcalculating the stability coefficient of the structures on the basis of span-width ratio isproposed.For the tube-gusset plate connections,by decomposing the resultant force of eachbranch pipe into vertical force N,shear force Q and moment M,the failure model andultimate bearing capacity of the connections under each force is obtained,especiallythe formula for calculating the ultimate bearing capacity of the connections undervertical force or moment is proposed.Finally,the interaction formula for N–M isobtained by analysis.Field testing of the structure is conducted to obtain the vibration performance ofthe trestle bridge, according to the test in different work state, the vibration of thestructure is mainly produced by the rollers, furthermore the natural frequency of thestructure obtained by test agrees well with the result from FEM.