고체역학 (Beer) — Introduction—Concept of Stress: Problem 1.68

1.68 A force P is applied as shown to a steel reinforcing bar that has been embedded in a block of concrete. Determine the smallest length L for which the full allowable normal stress in the bar can be developed. Express the result in terms of the diameter d of the bar, the allowable normal stress \(\sigma_{all}\) in the steel, and the average allowable bond stress \(\tau_{all}\) between the concrete and the cylindrical surface of the bar. (Neglect the normal stresses between the concrete and the end of the bar.)