Study Of Model Investigation Of Long List Shear Studs In Steel-concrete Composit Constructrue

Steel-concrete composite is one of the key structures in long span hybrid beam cable-stayed bridge, the carrying capacity of this stucture is directly related to the safety and durability of the bridge. Although China has built more than a dozen bridges like this, and lots of researches on steel-concrete composite have been done, there are still many problems could be studied in transmission power mechanism, reasonable structure design and simulation calculation ,because of the particularity and complexity of the combination of steel-concrete structures its own. In this paper, the group shear studs push-out model test for study the mechanical behavior of long list of shear studs , and the simplified model static test has been carried out, whose engineering background is Wuhan Erqi Yangtze River Bridge.To study the force of the long list of shear studs in steel - concrete composite section , a group studs push-out test model was produced. The force, sliding, bearing capacity of intensive group Studs was analyzed by model test and finite element . The results showed: the damage of the test in the form of shear studs cut; the distribution of the group studs' nominal shear along the vertical is saddle-shaped distribution; as the nails in the limit loads are able to achieve the ultimate bearing capacity of a single nail, screw the carrying capacity of groupcarrying capacity can be multiplied by a single nail calculated the number of shear studs; the existence of bonded friction, resulting in the force of group Studs are uneven, and when its in a small load, the uniformity coefficient up to 2 or more.The force transfered by bond friction parts , shear transfer and bearing plate in section of the steel concrete composite, and therefore its carrying capacity is depending on the weaker part. In this paper, long list of studs'shear force and slip were tested and analyzed by model test , results show that, bearing plate and the prestressing tendon made the force transmission form in steel-concrete composite abd group studs changed a lot. It is different from the push-out test, the longitudinal distribution of shear studs steel concrete composite was a linear basicly, nonuniformity of force in shear studs is larger than the group studs push-out test.Because the force of steel-concrete composite is complex, of which the carrying capacity of shear studs and shear stiffness there is no clear specification requirements.In this paper,through analyzed the calculate methods of shear studs in the relevant national and international regulations , different calculation methods were identified for different situations, and a more reasonable calculation method were obtained according to compare with the test results.In addition, the results show that the design of Wuhan Erqi Yangtze River Bridge'group studs have greater safety margin.