Experimental study on the effect of spliced reinforcement in high strength concrete beams

High strength concrete is often used in concrete structures such as bridges and high-rise buildings. An experimental test program was developed to examine the effects of spliced reinforcement in tension zones on the overall behavior of high strength concrete beams. Four design parameters were selected for this study including lap end shape (straight or bent), the number of shear stirrups, the percentage of steel cut off (25% and 50%), and the grade of steel reinforcement (A36 and A615). The effect of these four design parameters on the load-deflection behavior and cracking pattern were investigated utilizing fourteen high strength concrete beams with an average compressive strength of 97.7 MPa (14,170 psi). The beams were loaded such that the lap splice fell under the pure bending region. The load-deflection responses of beams and the crack patterns are reported in this paper.