Abstract
This study aims to clarify the shear resistance mechanism of reinforced concrete and prestressed concrete tapered beams without stirrups. Three series of seven beams with different parameters (a/d ratios and prestress levels) were tested. The results showed that there is no effect of the taper on the short beam due to the arch action. The slender RC tapered beam (2.5<a/d<4.5) had the higher shear capacity, while the RC tapered beam in large a/d ratio (a/d equals to 5.0) had the smaller shear capacity. When the prestressing force was introduced, the tapered beam again had the larger shear capacity. In addition, nonlinear FEM analyses were conducted to complement the experiments and verify the results, which showed a good agreement including load-deflection curves, load capacities, and crack patterns. A new evaluation method for the shear capacity of tapered beams without stirrups was finally proposed, by determining the location of the critical section through the nonlinear FEM analyses.
