Study On Behaviors Of Square Concrete Filled Steel Tubular Beams And Columns And Square Concrete With Reinforce Filled Steel Tubular Beams And Columns

Through investigating the damages caused by earthquakes, people have realized the design of columns and beams play a key role in preventing the collapse of building in strong earthquakes. In particular, with the increase of height and span of building, columns have to bear higher and higher axial load and beams have to bear higher and higher bending moment. So the beams and columns are required to have high strength as well as high ductility to prevent the collapse of building in strong earthquakes for the safe. Based on the summary about the present research on steel reinforced concrete columns and beams, a new model the square concrete with the reinforce filled steel tubes is put forwards. In the new model, the reinforce is inserted into concrete-filled steel tubes-square concrete with the reinforce filled steel tubes (It is subjected to the concrete filled steel tube with square section). Based on the experiment and the finite element method (FEM), the mechanical properties and effect factors of the square concrete filled steel tubes and the square concrete with the reinforce filled steel tubes are researched. The major contents are summarized as follow:Based on the experiments of short composite columns subjected to axial compression, the working feature, load-carrying and ductility of the square concrete filled steel tubes and the square concrete with the reinforce filled steel tubes are analyzed and major factors of effecting the feature are carried out.According to the flexural experiments of the composite structure, the working process is discussed, breaking features are compared and major factors that effect the flexural mechanical are analyzed.According to the stress-strain model and the FEM, the structural model is created. Through the simulated load-displacement curve of the composite structure and the experimental load-displacement curve, it can conclude if the model is correct.. Based on the correct model, it goesto analyze more structures to supple the test. Through the supplemental data and the test result, formulas used for predicting the ultimate bearing capacity are presented. It compares formulas with the design standard with the test result and simulated result.