[amp_mcq option1=”Is greater than the depth of critical neutral axis, the concrete attains its maximum stress earlier” option2=”Is less than the depth of critical neutral axis, the steel in the tensile zone attains its maximum stress earlier” option3=”Is equal to the depth of critical neutral axis; the concrete and steel attain their maximum stresses simultaneously” option4=”All the above” correct=”option3″]<\/p>\n
The correct answer is: C. Is equal to the depth of critical neutral axis; the concrete and steel attain their maximum stresses simultaneously<\/strong>.<\/p>\n The depth of the neutral axis is the point in a beam where the strain is zero. The critical neutral axis is the depth of the neutral axis when the beam is just on the verge of failure.<\/p>\n In a doubly reinforced beam, the concrete and steel are both under tension. The concrete has a lower modulus of elasticity than the steel, so it will reach its maximum stress at a lower strain than the steel. The steel will continue to stretch until it reaches its yield stress, while the concrete will continue to crack and lose its load-bearing capacity.<\/p>\n If the depth of the actual neutral axis is equal to the depth of the critical neutral axis, then the concrete and steel will reach their maximum stresses simultaneously. This is the ideal situation, as it means that the beam will be able to carry the maximum load without failing.<\/p>\n If the depth of the actual neutral axis is greater than the depth of the critical neutral axis, then the concrete will reach its maximum stress before the steel. This means that the steel will still have some load-bearing capacity left when the concrete fails. This is not ideal, as it means that the beam will have a lower load-carrying capacity.<\/p>\n If the depth of the actual neutral axis is less than the depth of the critical neutral axis, then the steel will reach its maximum stress before the concrete. This means that the concrete will still have some load-bearing capacity left when the steel fails. This is also not ideal, as it means that the beam will have a lower load-carrying capacity.<\/p>\n","protected":false},"excerpt":{"rendered":" [amp_mcq option1=”Is greater than the depth of critical neutral axis, the concrete attains its maximum stress earlier” option2=”Is less than the depth of critical neutral axis, the steel in the tensile zone attains its maximum stress earlier” option3=”Is equal to the depth of critical neutral axis; the concrete and steel attain their maximum stresses simultaneously” … <\/p>\n