Question

According to IS 456, when assessing the strength of a structure or structural member for the limit state of collapse, the value of partial saftey factor for concrete (material) should be
1. 1.15
2. 2.00
3. 2.50
4. 1.50
5. 3.00

Answer 1

Correct Answer - Option 4 : 1.50

Explanation:

The design strength of concrete and steel is obtained by dividing the respective characteristic strengths by appropriate partial safety factors for concrete and steel.

• At ultimate loads i.e. at ultimate limit state,
  • Partial safety factor for concrete, γ_c = 1.5
  • Partial safety factor for steel, γc = 1.15
• ​At serviceability limit states, 
  • Partial safety factor for concrete, γc = 1 
  • Partial safety factor for steel, γc = 1