Deformation Analysis Of Fabricated Steel Truss-Concrete Composite Beams

This paper,which depends on the research project entitled with " Basic theoretical research of large span steel truss-concrete composite continuous rigid frame bridge " from the Ministry of transportation(project number: 2013319814040),with the Guangfuzhao Highway Qingqichong Bridge as the engineering background,completed experimental and theoretical study on whole deformation performance of fabricated steel truss-concrete(STC)composite beams.The main research work includes the following contents:(1)Deformation performance test research of the prefabricated steel trussconcrete composite beams are carried out.The deflection change rule and the interface slip law under each loading stage are studied comprehensively.From load applied to beam damage,the whole deflection of the test beam can be subdivided into three stages as followed: total cross-section work stage(K1),work stage with cracks in deck(K2)and load stage after deck interface cracking.(2)Aimed at test beam,with using finite element numerical fitting method,deriving the simplified calculation formula,which can transfer open-spandrel steel truss into solid-web section beams through considering the effect of shear deformation.With the crack developing of test beam,and using the simplified calculation to analyze its deflection,and the results demonstrate that the analysis results can match the test results very well.(3)Combined with the finite element,simplifying the stiffness values of elastic connection,which is used to simulate the PCSS shear connection;the stiffness values can be calculated through creating composite sector solid finite element model,and the values will be used in the test beam finite model,whose analysis results can match the test results well.Then,the paper completed parametric analysis on the stiffness with the variables,such as the stud diameter d and the stud arrangement spacing s,and the stiffness parameterized formula is established.Using stiffness parameterized formula to analyze Qingqichong Bridge,the predicted value of structure is given.