LECTURE-09 balanced section l Under reinforced section l Over reinforced section l Types of Sections
There are 3 types of RCC sections Balanced, under reinforced and over reinforced sections In Balanced Section crushing strain in concrete reaches yielding of steel simultaneously, in Under Reinforced section yielding of steel starts first and than it reaches crushing strain in concrete, in over reinforced sections crushing of concrete starts first than yielding of steel. In balanced section failure occurs simultaneously and is called balanced or critical failure. In under reinforced sections failure occurs by yielding of steel and is called as primary tension failure. In over reinforced sections failure occurs by crushing of concrete and is called primary compression failure. Design codes prohibits over reinforced design as concrete is brittle and brittle failure will not give sufficient warning before failure because it is primary compression failure