CIVL 430 Lecture Notes - Stress (Mechanics), Stirrup
Document Summary
Understand two basic bond mechanisms between concrete and steel. Understand how the uniform bond stress model is used to determine requirements of reinforcement development lengths. Understand the factors influencing required development length. Be able to calculate required development length according to a23. 3 with and without hooks. Understand factors influencing bar cut-off locations and how to determine location of bar cut-offs. Understand how bar cut-offs are typically determined in building design. At cracks, all tensile stress carried by reinforcement. Between cracks, tensile stress shared between concrete and reinforcement. Two mechanisms transfer stress from reinforcement to concrete: Forces on concrete act at an angle, related to the shape of the deformation. Radial component can cause splitting cracks parallel to the bar. Factors influencing constant c: quality of the concrete/bond. Top bars in beam tend to be surrounded by lower quality concrete due to bleeding of water from the concrete below during vibration. Clear cover db and bar spacing 1. 4 db.
