Bar development and tension lap splice of high-strength reinforcing steel
High-strength reinforcing steel with yield strengths up to 100 ksi have been implemented in design code, but it is not common in practical bridge design. High-strength reinforcement bears opportunities for higher load-carrying capacity, reduced congestion, cost savings, and corrosion-resistance in bridge components. However, the serviceability and the validity of current code provisions shall be further investigated for state departments of transportation to apply this material in practice. In particular, bar development and tension lap splice provisions of high-strength reinforcement should be studied, and the serviceability performance in terms of crack control must be evaluated. There is limited data on the serviceability performance of beams with high-strength rebar using larger bar sizes. Therefore, the research team at the University of Texas aims to expand the database of beam-splice tests by conducting four-point bending tests on four specimens containing No. 11 bars for longitudinal reinforcement either in ASTM A615 Grade 60 or Grade 100 steel. Through the results, the effects of steel grade and the presence of a lap splice on strength and serviceability performance can be evaluated. Furthermore, design recommendations and conclusions on the applicability of current design code development length and lap splice provisions using high-strength reinforcing steel are drawn.