Structural Performance And Experimental Research Of Steel Girder-Full Depth Deck Panel Composite Continuous Bridges

Steel girder-full depth deck panel composite continuous bridge is adapted to fabricated construction without scaffolding by using clustered studs as connection. This structure can enhance construction speed apparently. The construction without scaffolding decrease interference to traffic under bridge and improve the level of bridge industrialization. According to structural characteristics of this type of bridge, experiment and theoretical studies are carried out. The main work and research results are as follows:(1) Establish of Srtructrue systerm:Reasonable structural system and details of the Steel girder-full depth deck panel composite continuous bridge have been studied, which is composited of I-steel girders and full-depth deck panels by clustered studs. A series of standard designs are also provided.(2) Test of new type composite beam under positive moment:A group of beams under positive moment are tested to study the influence of the spacing of shear pocket, the degree of shear connection. It shows that flexural bearing capacity of test beams is decreased in range of 2% with decline of the degree of shear connection in positive moment test. And elastic stiffness, ductility is decreased apparently and slip between steel girder and concrete plate are increased.(3) Test of new type composite beam under nagative moment:A group of beams under negative moment are tested to study the influence of the force ratio of composite section. Stiffness is decreased apparently with incline of section force ratio in negative moment test. But the flexural bearing capacity is similar. Measures must be taken to strengthen the U-bar joint because it is the weakness of composite beam under negative moment. The incline of force ratio can promote cracking load and inhibitor development of cracks.(4) FEA modle and factors analysy:FEA model based on space of pockets are built to analysy the influence of space of pockets to composite beams under positive and negative moment. It comfirms the feasibility of enlarging space of pockets to 1200mm.(5) Theory analysy and Calculate method:Giving formular adapted to clustered studs connected composite beams by comparering with test results. Formular of U-bar joint composite section is risen based on ASTM models. Derivation crack width under negative moment are proposed which are suitable for the steel girder-full depth deck panel composite bridge by summarizing existing formulas and test result.(6) Construction suggestions:Arrange appropriate construction sequence according to mechanical behavior of steel girder-full depth deck panel composite continuous bridge under construction and give suggestions to each construction procedure. The spacing of cross frames should be designated between 1/4L0 and 1/2L0 in order to ensure the global stability of steel girder. And the local stability of top flange can be guaranteed when the ratio of flange's width to thickness (bf/tf) ranges from 7 to 12.