For M 150 grade concrete (1 : 2 : 4) the moment of resistance factor is
A. 0.87
B. 8.50
C. 7.50
D. 5.80
Answer: Option B
Solution (By Examveda Team)
M150 grade concrete refers to a mix ratio of 1:2:4 (Cement : Sand : Aggregate), where the characteristic compressive strength (fck) is 15 N/mm².The moment of resistance factor (R), also known as the limiting moment of resistance per unit width and square of effective depth, is a design parameter used in the limit state method for RCC beam design.
According to standard design aids and tables based on IS 456:2000, for M15 grade concrete, the commonly referred value of the moment of resistance factor is approximately 8.50.
Option A: 0.87 is incorrect, as it usually refers to the partial safety factor or percentage of steel yield stress, not the moment of resistance.
Option C: 7.50 and Option D: 5.80 are not the correct standard values for M150/M15 grade concrete.
Therefore, the correct answer is Option B: 8.50.
This Question Belongs to Civil Engineering >> RCC Structures Design
Correct answer A (0.87)
Resistance factor=0.7*square root of fck
=0.7×√150
=8.57
As per is code 456- 2000 R is the moment of resistance factor, does not depend on dimensions,its called design constant , the value of R for M15
1. mild steel =0.867
2. Fe 415=0.65
3. Fe 500=0.58
Can you please explain???