بررسی شکلپذیری تیرهای بتن آرمهی وصلهدار

Abstract

In this research, the ductility of lap-spliced concrete beams reinforced with steel and FRP bars is analyzed. A number of 16 beam specimens reinforced with steel bars and 7 with FRP bar were designed and manufactured in real sizes and dimensions for laboratory experiments. The parameters of concrete compressive strength, amount of transverse reinforcement over the splice length and the diameter of longitudinal bars, are selected as the main variables for the beam specimens. Mid-span displacements and the corresponding forces were obtained by means of a hydraulic jack, load cell, LVDT and a Data Logger set. The force versus mid-span displacement curves were obtained using the experimental data. A ductility index which has been defined by researchers, was used to evaluate the ductility of the specimens. Comparison of the ductility index of different specimens shows that the compressive strength of concrete and the amount and the bar diameter of the transverse reinforcement over the splice length, has a major effect on the ductility of lap-spliced reinforced concrete beams. The results show that by using an appropriate amount of transverse reinforcement, a satisfactory ductility response for different compressive strengths of concrete can be obtained.