EK263

Proportioning reinforced concrete structural members by ultimate-strength design is based on the following assumptions:

1. Strain in concrete is the same as in reinforcing bars at the same level, provided that the bond between the steel and concrete is adequate.
2. Strain in concrete is linearly proportional to the distance from the neutral axis.
3. Plane cross-sections continue to be plane after bending.
4. Tensile strength of concrete is neglected because concrete’s tensile strength is about 10% of its compressive strength and cracked concrete is assumed to be not effective.