Minimum Base Width of Elementary Profile

Q. The minimum width in the elementary profile of a gravity dam required to retain the water with a head of 60 m is _________ m.
$[\text{Take}\mu =0.65,G=2.4,C=1]$

1. 65.93

Q. Height of a gravity dam of elementary profile, whose base width is B and specific gravity of material is G will be (For no tension condition)

1. $B\sqrt{G}$
2. $\sqrt{BG}$
3. $BG$
4. $B/\sqrt{G}$

Q. The base width of a solid gravity dam is 25 m. The material of the dam has a specific gravity of 2.56 and the dam is designed as an elementary profile ignoring uplift. What is the approximate allowable height of the dam?

1. 64 m
2. 40 m
3. 164 m
4. 80 m

Q. The base width of an elementary profile of gravity dam of height H is b. The specific gravity of the material of the dam is G and uplift pressure coefficient is K. The correct relationship for no tension at the heel is given by

1. $\frac{b}{H}=\frac{1}{\sqrt{G-K}}$
2. $\frac{b}{H}=\sqrt{G-K}$

3. $\frac{b}{H}=\frac{1}{G-H}$

4. $\frac{b}{H}=\frac{1}{K\sqrt{G-K}}$

Q. Height of a gravity dam of elementary profile is 22 m. Specific gravity of the dam material is 2.3. The coefficient of friction at the base of dam is 0.52. If uplift is not considered, the minimum base width of the gravity dam should be _____ m

1. 9
2. 15
3. 19
4. 24

Q.

A concrete dam holds 10 m of static water as shown in the figure (not drawn to the scale). The uplift is assumed to vary linearly from full hydrostatic head at the heel, to zero at the toe of dam. The coefficient of friction between the dam and foundation soil is 0.45. Specific weights of concrete and water are 24 $kN/m^3$ and 9.81 $kN/m^3$, respectively.


For NO sliding condition, the required minimum base width B (in m, round off to two decimal places) is

1. 10 m
2. 12 m
3. 16 m
4. 9 m

Q. If $\rho$ is the specific gravity of the material used in the design of a masonry dam of triangular section, then the ratio between the height and base width of the dam for structural safety and stability is equal to

1. $\sqrt{2\rho }$
2. $\sqrt{\rho }$
3. $\frac{1}{\rho }$
4. $\frac{1}{\sqrt{\rho }}$

Q. If the material of dam is having specific gravity of 2.6 and the base width of 30 m then the approximate allowable height of dam is

1. 5 m
2. 32 m
3. 48 m
4. 55 m

Q. An elementary profile of a gravity dam yields the following data:
Specific gravity of concrete = 2.5,
Coefficient of friction, $\mu =0.5,$
Height of dam= 100 m,
The base width of the dam, considering no uplift, will be ___________ m.

1. 80