SHEAR CAPACITY AND DESIGN STRENGTH OF REINFORCED AND PRESTRESSED MEMBERS CAST WITH HIGH PERFORMANCE CONCRETE

摘要

Shear in cracked structural concrete is principally resisted by tension in the shear reinforcement and aggregate interlock along diagonal cracks. In members cast with High Performance Concrete (HPC), the diagonal cracks may be much smoother than they are for normal strength concretes and this can reduce the effectiveness of the aggregate interlock mechanism. This paper illustrates that long-standing US Building Code expressions do not provide accurate estimates of the shear capacity of concrete members for a range of concrete cylinder strengths. By contrast, a computer-based design tool based on a model for concrete behavior is shown to provide reliable estimates.