Experimental Research On Stressing Performances Of Steel Reinforced Concrete Cantilever

There are some distinctions between the stressing performances of steel reinforced concrete cantilever and these of SRC simple beam with simple bending sector. The application of SRC cantilever in practical projects is also very frequent. So the research on the stressing performances of SRC cantilever is significant to Engineering.The experimental research of 12 SRC cantilevers, 2 reinforced concrete cantilevers and 2 SRC cantilever without steel bar and stirrup under concentrated force had been carried out in this thesis. The experimental process and phenomena had been described blow by blow and the primary analysis on test results had been preceded. The main test results including photos at failure, photos of crack-unfolding, load-deflection curves, flexure lines, bearing capacities, loads at cracking, width of cracks, mean space of cracks and length of plastic hinge had been given out in this thesis. Based on the aforementioned experimental results, categorization and comparison of failure mode of all specimens had been made, the unique feature and mechanism of crack-developing had been summarized and analyzed, the characteristics of load-deformation curves and flexure lines had been compared and analyzed, the unique feature of plasticity on bottom flange of steel shape had been analyzed.According to the practical stress level of steel shape and plane cross-section assumption, design formulas of normal section's bearing capacity of SRC cantilever had been deduced and built. To take into consideration of the influence of bond-slip on bearing capacity, strength reduction factor ? of steel shape had been introduced into the formulas. By deductive method ? was decided to be 0.92.The comparison among test results, calculated results by formulas of this thesis and these by formulas of tow codes had been made.Combining the unique feature of cantilever and test result, the equation of stress of steel bar between two adjacent cracks had been obtained. Based on the equation, the general formulas of crack width had been deduced and built. Theoretically, these formulas can be used to calculate width of crack at certain location. The equation of stress of steel bar between two adjacent cracks was decided to be damped cosine function. According to test result and existing research, all parameters of formulas of the maximum crack width were decided. The formulas of the maximum crack width were finally decided. The comparison between computed result by the decided formulas and test result had been made.