If the ratio of long and short spans of a two way slab with corners held down is r, the actual reduction of B.M. is given by
A. $$\frac{5}{6}\left( {\frac{{\text{r}}}{{1 + {{\text{r}}^2}}}} \right){\text{M}}$$
B. $$\frac{5}{6}\left( {\frac{{{{\text{r}}^2}}}{{1 + {{\text{r}}^2}}}} \right){\text{M}}$$
C. $$\frac{5}{6}\left( {\frac{{{{\text{r}}^2}}}{{1 + {{\text{r}}^3}}}} \right){\text{M}}$$
D. $$\frac{5}{6}\left( {\frac{{{{\text{r}}^2}}}{{1 + {{\text{r}}^4}}}} \right){\text{M}}$$
Answer: Option B
Solution (By Examveda Team)
The question is about two-way slabs in Reinforced Cement Concrete (RCC) structures.Two-way slabs are supported on all four sides and the load is carried in both directions (length and width).
The ratio 'r' refers to the ratio of the longer span to the shorter span of the slab.
When the corners of a two-way slab are held down (meaning they are prevented from lifting), it changes how the slab bends (its bending moment, or B.M.).
Because the corners are held down, the bending moment is reduced.
The question asks which formula correctly represents this reduction in bending moment.
The correct formula, representing the reduction, is: $$\frac{5}{6}\left( {\frac{{{{\text{r}}^2}}}{{1 + {{\text{r}}^2}}}} \right){\text{M}}$$ , where M is the original bending moment.
So, the answer is Option B.
This Question Belongs to Civil Engineering >> RCC Structures Design
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Comments (1)
Distribution of shear intensity over a rectangular section of a beam, follows:
A. A circular curve
B. A straight line
C. A parabolic curve
D. An elliptical curve
If the shear stress in a R.C.C. beam is
A. Equal or less than 5 kg/cm2, no shear reinforcement is provided
B. Greater than 4 kg/cm2, but less than 20 kg/cm2, shear reinforcement is provided
C. Greater than 20 kg/cm2, the size of the section is changed
D. All the above
In a pre-stressed member it is advisable to use
A. Low strength concrete only
B. High strength concrete only
C. Low strength concrete but high tensile steel
D. High strength concrete and high tensile steel
In a simply supported slab, alternate bars are curtailed at
A. $${\frac{1}{4}^{{\text{th}}}}$$ of the span
B. $${\frac{1}{5}^{{\text{th}}}}$$ of the span
C. $${\frac{1}{6}^{{\text{th}}}}$$ of the span
D. $${\frac{1}{7}^{{\text{th}}}}$$ of the span
Correct option B