Analysis Of Interface Behavior On Steel-Concrete Composite Beams And Experimental Study Of Load Distribution Width On Stiffened Steel Plate And Concrete Composite Plates

At recent 20 years, steel-concrete composite structure develops quickly in our country, which would have wide application. There are still a lot of issues that need to be solved in field of composite structure, compared with traditional reinforced-concrete structure. Combining theoretical analysis, experimental study, numerical simulation methods, and taking Guangzhou Foshan Dongping Bridge as study background, the two issues, interface behavior of steel-concrete composite beam and load distribution width of steel-concrete composite plate, are studied in this dissertation. The main research achievements are summarized as the following:1. The redistribution of longitudinal shear force, which is caused by the plastic deformation of flexible connectors such as studs, is studied for a simply supported composite beam under uniformly distributed load. Based on the actual working behavior of the connectors, the full-range mechanic behavior of interface is divided into three work-stages, including elastic stage, elasto-plastic stage and failure stage. Simplified analytical models for the redistribution of longitudinal shear force are established and a set of formulae for calculating longitudinal shear force and axial force are presented in each stage. It is helpful to study exactly mechanics behavior of composite beam.2. The formulae for calculating curvature of composite beam are presented based on the first principles of curvature and the simplified analytical models for the redistribution of longitudinal shear force. Based on the equations of curvature and axial force taken by concrete flange plate, the formulae for calculating slip, slip strain and deflection of composite beam are presented at different work-stage. The consequence considering the influence of slip and redistribution of longitudinal shear force has theoretical value.3. Stiffened steel plate and concrete composite plate is a new kind of composite plate. Two different structure-system plates are designed such as simply supported composite plate and cantilever composite plate, and full-scale experiment is carried out. The difference of equivalent standards for calculating load distribution width controlled by bending effect is analyzed. And the...